Showing posts with label Carbohydrate. Show all posts
Showing posts with label Carbohydrate. Show all posts

Tuesday, November 27, 2007

Higher Carb, Higher GI and High GL = Higher Risk for Diabetes

A study published in the November 26, 2007 edition of the Archives of Internal Medicine, Prospective Study of Dietary Carbohydrates, Glycemic Index, Glycemic Load, and Incidence of Type 2 Diabetes Mellitus in Middle-aged Chinese Women, reached a startling conclusion, "High intake of foods with a high glycemic index and glycemic load, especially rice, the main carbohydrate-contributing food in this population, may increase the risk of type 2 diabetes mellitus in Chinese women." [emphasis mine]

In the study, researchers reviewed the food consumption records of 64,227 Chinese women with no history of disbetes or chronic disease for 4.6-years. They conducted in-person interviews and collected data about dietary habits, exercise and lifestyle factors. Over the study period, 1,608 women developed diabetes (defined in the study as a fasting blood glucose greater than or equal to 126mg/dL.When the researchers analyzed the dietary habits they found the risk of diabetes was 78% higher in women consuming the most carbohydrate each day, with rice making up the largest portion of carbohydrate in this population of women.

As MedPage Today noted, "In a multivariate analysis, women in the highest quintile of carbohydrate intake had a 28% greater risk of diabetes compared with women in the lowest quintile (95% CI: 1.09 to 1.50). Women who consumed the most rice had a 78% greater risk of diabetes compared with women who had the lowest rice consumption (95% CI: 1.48 to 2.15)." [emphasis mine]

What is really interesting, at least from my perspective, is that the women in the lowest quintile ate a similar calorie load as those in the highest quintile - yet the diets of the two groups were vastly different with not only carbohydrate, but also protein and fat. The women with the lowest risk consumed an average 84g a day of protein and 43g of fat - the women with the highest risk consumed an average 60g of protein and just 22g of fat.

The carbohydrate intake of those found to have a high risk for developing diabetes wasn't shocking by American standards - 338g per day! Those in the lowest quintile consumed 22% less carbohydrate on average, or 264g a day. Another interesting tidbit from the study data - those consuming less carbohydrate actually had a higher intake of fiber - 13.8g versus 9.3g per day.

Friday, August 10, 2007

Rules to Maintain a Balance

Sometimes when we first start a low-carb diet, our bodies react in ways that might seem off, so the next rule addresses the "potty problems" that some find when they're starting on a new low-carb diet.

Rule 12:
  • If you are constipated, mix a tablespoon or more of psyllium husks in a cup or more of water and drink daily. Or mix ground flaxseed into a shake or sprinkle wheat bran on a salad or vegetables.

This rule compliments rule 11 - that is it helps with strategies to avoid and counteract constipation. Water and high-fiber supplements are recommended to help maintain regularity. With any changes to your daily diet your body may experience short-term bouts of constipation and the above rule helps get you through this. It also reinforces for the long-term what works for constipation naturally rather than chemically processed products or sugar-laden fiber mixes that are commercially available.

The secret of this rule is that it is providing you with natural ways to alleviate constipation, not only in beginning, but in the long-term as you look to maintain your goal weight if you still have occasional issues.Important in this rule is to understand what it is to be constipated.

Constipation is not just not having a bowel movement for a couple of days - it is having the urge to have a bowel movement and being unable to go to the bathroom! When you do finally go, the feces are dry and hard. While not going for a day or two may be alarming, if you are not uncomfortable, you are probably not constipated. When you are constipated it is important to be sure you are getting plenty of water and increasing your fiber so that you are able to go without straining. Drinking water as instructed in the previous rule along with this one give you the tools to regulate yourself naturally.

The last rule we'll look at speaks directly to the recommendation to take, at minimum a good multivitamin with minerals. It's pretty much a universal given no matter what type of diet you eat that you should include a vitamin each day, and the same is true for those starting a low-carb diet.

Rule 13:

  • At a minimum, take a good daily multivitamin with minerals, including potassium, magnesium and calcium, but without iron.

Many people starting out on a low-carb diet with both feet and take a large number of supplements.

In this rule, Dr. Atkins makes it clear that at minimum you need a good multivitamin each day. Also specifically mentioned are minerals, which are important to maintain electrolyte balance, especially when you're starting a low-carb diet and will experience a metabolic shift to burn fat primarily instead of glucose, which releases a lot of water from stored glycogen.

Much like the rule on water (fluid) intake is universally agreed as a "good rule", so too is this rule. While some people will benefit from additional supplements to their daily multi-vitamin, it is not necessary to start with more than a good multi-vitamin with minerals.

In the long-term, maintaining this habit of taking a good multivitamin is also a good idea no matter what diet you follow.

It is important to note with this rule that the multi-vitamin must have potassium, magnesium and calcium - these control and keep in balance your electrolytes (your body salts), so chooing one with a good balance and ratio of these minerals is important. Important too is to use a multi-vitamin not packed with iron (unless you have a medical reason to take additional iron) since your diet will now contain enough iron (if you follow it correctly) each day without additional supplementation of iron. Too much iron is as deterimental to your health as too little. Unless you have a reason to take more iron, find a good multi-vitamin without iron!

The secret within this rule is to learn to keep a balance - insure you're getting all the nutrients you can with real food and have a multivitamin each day to be sure if you missed somewhere along the way, you had it in your vitamin.

This rule and the one before it aren't about extremes - it is about balance.

By taking care of potential "potty problems" and including a good multivitamin each day, you're developing a habit that will enhance your ability to get all of your nutrients each day - even on those days you may not eat "well".

Wednesday, August 08, 2007

Rule Eight: Keep it Real

A low-carb dietary approach is easy to maintain almost anywhere you can eat - at home, on the road or in a restaurant. The key is to carefully consider your options available and understand where carbs are most likely to be found in things "allowed" when they're prepared by others. When you're cooking at home, you know what ingredients you're using; on the road or in a restaurant, odds are high that the chef is using ingredients you won't be including in a controlled-carb diet.

Rule 8:
  • Eat out as often as you wish but be on guard for hidden carbs in gravies, sauces and dressings. Gravy is often made with flour or cornstarch, and sugar is sometimes an ingredient in salad dressing.

In an effort to keep it real, rule eight establishes that it's perfectly reasonable to eat out, with a caution to be aware of ingredients used in food preparation. As one more rule, it again repeats an underlying theme within all the rules - take responsibility for what you do eat.

Simply put, do not assume anything in a restaurant is acceptable unless you ask or ingredients are clearly stated on the menu! Where ingredients are not disclosed on a menu, learning how to ask and actually taking the time to ask about ingredients and food preparation is something you'll become accustomed to over time - and in the long-term will be an invaluable asset in your tool-box of strategies to insure you're eating controlled-carb for life!

When you eat out, in addition to the food you get, you're paying for a service - to have your food prepared - so be fully prepared to expect to be served acceptable food for your diet. Start by asking that things be prepared in a way that is acceptable for you or ask for guidance as to what else is acceptable if the chef cannot prepare something without particular ingredients. The basic ingredients, at minimum, you must insist are not included in your meal because of carbohydrate content are sugar, corn starch, arrowroot, potato starch and flour. The standard food ingredients to not be included are bread crumbs, breading, rice, pasta and potatoes, sugar based marinades, high carbohydrate salad dressings, etc.

In addition, you also want to be careful to avoid dishes prepared with shortening, margarine and other fats high in trans-fats. This isn't explicit to the rule above, but given our current knowledge, it's something to avoid when eating out.

If a restaurant is having a difficult time accomodating you, choose a simple salad wth oil and vinegar for your dressing, have a basic protein grilled (no marinade) baked or broiled, and some steamed vegetables.

In all the years I've restricted carbohydrate in my diet, I've never been unable to find something on a menu that's acceptable. Sometimes it means being a bit creative, but as long as a restaurant has basic foods, you can find something to eat as a meal while you're there.

Thursday, July 19, 2007

Rule Three: Vegetables & Fruits are Heart of Controlled-Carb

We hear much of a healthy diet is from eating fruits and vegetables. Research suggests there is a strong correlation between "good" health and "bad" health over the long-term when comparing the dietary habits of those eating a diet rich with fruits and vegetables to those consuming less than recommended levels.

Diets that strategically restrict carbohydrate are often criticized for lack of fruits and vegetables in the dietary approach. Much like the second rule getting lost in translation, from an allowance of a large variety of meats, poultry, fish, shellfish and game to a requirement to eat "fatty steaks, bacon, brie and cheeseburgers," by those unconvinced a low-carb diet is scientifically supported, rule three is often either ignored in the media and/or used to show how unsustainable carbohydrate restriction is in the long-term for someone to do forever.

How about we take a look, and see what the third rule actually says, and what it "pearls" it contains in both the short and long-term, and where vagueness may lead to misinterpretation:

Rule 3:
  • Eat no more than 20 grams a day of carbohydrate, most of which must come in the form of salad greens and other vegetables. You can eat approximately three loosely packed cups of salad, or two cups of salad plus one cup of other vegetables.

First, we know from the published books, that the Induction period is a minimum of two weeks; while one can, and many do, stay within the 20g of carbohydrate beyond two weeks, the above rule is in place for at least the first two weeks.

During this time, the person starting the low-carb diet is tasked with two things in this rule:

  1. limiting carbohydrate to just 20g a day and
  2. ensuring that most of those 20g carbs are from salad greens and other (allowed) vegetables.

As an example, the rule says this is "approximately" three loosely packed cups of "salad" (note not simply salad greens), or two cups of "salad" (again not simply salad greens) plus one cup of other (allowed) vegetables (without mention of raw or cooked state).

We also know that the plan includes a deduction of fiber, so the amount of non-starchy vegetables (and fruits which I'll get to in an upcoming post) - in cups - that one is expected to consume depends highly on which allowed vegetables are selected in a day. Regardless of which are included, a minimum 10g net (deducting fiber) must come from non-starchy vegetables!

We also plainly see that it is not *mandatory* to deduct fiber per the rule above; however, I strongly suggest folks do deduct fiber as it allows a greater intake of non-starchy vegetables, which are not only low in calories, but nutrient powerhouses. When you deduct the fiber, you're able to consume more essential nutrients than if you don't.

I've previously offered examples of how different selections of non-starchy vegetables may look in a day of eating on a plan allowing 20g net in a day. Once again, I am providing examples to emphasize, even at 20g net carbohydrate, where 10g net is the minimum, a low-carb plan - done properly - meets or exceeds intake recommendation of at least five servings per day in the Dietary Recommendations for Americans for fruits and vegetables.

Example 1

  • 1-cup green beans (cooked measure)
  • 2-cups Shredded Cos/Romaine Lettuce (raw)
  • 4-pieces Crimini Mushrooms (raw)
  • 1/4-cup Shredded Red Cabbage (raw)
  • 4 Cherry Tomatoes (raw)
  • 1-cup Spinach (raw)
  • Total Carbohydrate = 18g
  • Fiber = 8g
  • Net Carbohydrate = 10g
  • USDA Servings of fruits/vegetables = 5

Example 2

  • 1/2 Avocado (raw)
  • 3-cups Cos/Romaine Lettuce (raw)
  • 4 Cherry Tomatoes (raw)
  • 1/4 cup Shredded Red Cabbage (raw)
  • 1-cup Spinach (cooked measure)
  • 1/2-cup Broccoli Florets (raw)
  • 1/2-cup Sliced Cucumber (raw)
  • Total Carbohydrate = 24g
  • Fiber = 14g
  • Net Carbs = 10g
  • USDA Servings of fruits/vegetables = 6

Example 3

  • 2-cups Shredded Cos/Romaine Lettuce (raw)
  • 1/2-cup Cherry Tomatoes (raw)
  • 1-cup Spinach (cooked measure)
  • 1/2-cup Asparagus (cooked measure)
  • 1/2 cup Sweet Green Peppers (cooked measure)
  • Total Carbohydrate = 21g
  • Fiber = 9g
  • Net Carbs = 12g
  • USDA Servings of fruits/vegetables = 6

One can see from the examples above, depending on selections made from those fruits and vegetables allowed in the first two weeks, it is not difficult to meet the recommended intake of 5-or-more servings of fruits and vegatables.

The aim to include a minimum of 10g (of the 20g allowed) from non-starchy vegetables is a "must" in the rule above.

It is also clearly stated as a "minimum," and therefore understood that if you would like to include 12g, 15g or more from non-starchy vegetables in lieu of other foods that have carbohydrate, that is also allowed.

So, if one is cognizant of and desiring more than the minimum intake of fruits and vegetables, they are completely allowed to consume more - with the only restriction being not to exceed 20g net (deducting fiber) during the first two weeks.

Must you aim to consume half your allowed carbohydrate from fruits/vegetables? YES

Can you eat more fruits/vegetables (allowed ones), say 12g, 15g, 18g? YES

Can you deduct fiber? YES

Do you have to? NO (but doing so allows a greater intake of fruits/vegetables and associated essential nutrients)

With all that said, and focus on what all the rules mean for the long-term, I contend that one is expected to continue eating this level (as minimum each day) as they progress toward the long-term eating. I believe that this is one more "foundational" part of carbohydrate restricted diets in the long-term and something intended to be continued as one increases carbohydrate and includes a wider selection of foods, including more vegetables, fruits, nuts, seeds, legumes, and if desired, even whole grains.

Many folks say a low/controlled-carb diet is a way of life, yet find it difficult to take what they start with - 20g net (deducting fiber), of which most must be provided by non-starchy vegetables, a 10g minimum each day - and maintain that aspect as one solid foundation to build upon as they continue to lose weight and then maintain their weight.

Old eating habits start to creep back with more carbs; habits such as preferrentially selecting sweeter foods or grains (even if whole grain) with consumption of non-starchy vegetables waning as one re-introduces more carbohydrate.

If one takes this rule, and continues to extend it --- fully --- until they reach 40g net carbohydrate each day (deducting fiber), they will be consuming incredibly healthful levels of fruits and vegetables, and will be able to eat a very wide variety of them too. That is, until 40g carbohydrate is achieved in the diet during weight loss, one must always include half those carbohydrates from fruits and vegetables with each incremental increase in carbohydrate. (Beyond that, it is increasingly difficult to continue adding more non-starchy vegetables and fruits due to their bulk; you can, of course - it's just not as easy to do).

Now that isn't exactly stated explicitly in the rule, but it is from my experience and those I've given assistance, one significant contributor to maintenance of weight in the long-term. That's because if you're aware of and including a lot of fruits and vegetables (specifically non-starchy vegetables and low-glycemic load fruits) it is difficult to consume excess calories each day over the long-term.

It becomes much easier to consume excess calories when you "play" the carb game (like many play the "points" game with Weight Watchers) and make choices to stay within a number, rather than focus on quality of choice.

But if you're committed to making sure that, no matter what intake of carbohydrate you reach (60g, 90, 120g or more), that you always are sure you include at least 10g net minimum at the start and then 20g minimum (net) from non-starchy vegetables/low glycemic-load fruits as you continue along, you'll have a favorable calorie intake that helps maintaining weight easier.

As you add back carbs, this rule must remain in your eating habits, even if you only stick with 10g net as minimum (which I don't suggest you do) as you're learning in the beginning - you cannot add back carbs and eliminate or reduce how many vegetables and salads you eat each day and expect to maintain your weight using grains, nuts, fruits, etc. as your primary source of carbohydrate later....you must always maintain a level of carbs from your vegetables and salad greens - even in maintenace.

This rule, like rule two, is taking you "back to basics" - helping you learn, step-by-step, how to nourish your body with high quality nutrients from real foods; over time you're encouraged to include a wider variety of non-starchy vegetables, low glycemic-load fruits, nuts, seeds, legumes and more, and the starting basics for the diet should be extended out for the long-term; that is, establish now, at the start, that as part of your long-term habitual diet, non-starchy vegetables and low-GL fruits will be a large part of your overall diet - your body will thank you!

Thursday, June 07, 2007

Back to Our Regularly Scheduled Program

You may recall the alarming headlines reported here that suggested a high-fat meal was very risky to endothelial function; one went so far as to suggest just one bite of a burger might kill you!

Seems some researchers thought maybe it's a good idea to see what effect a high-protein (low-carb) and low-fat (high-carb) habitual diet might have on endothelial function over a longer period of time - say, maybe a year?

Wonder why you haven't seen any headlines on the latest study - Effects of weight loss on a low-carbohydrate diet on flow-mediated dilatation, adhesion molecules and adiponectin - published in the British Journal of Nutrition?

Might be because the researchers found nothing significantly different between the two diets, and noted "weight loss does not improve FMD [flow mediated dialation]."

Paper gets published, media sees it, notes noting to see here, no sexy headlines....not quite juicy enough to waste readers time with (even though it contradicts those one-meal experiements), so let's just move on.

But wait!

Just because the study objective was to see effect (benefit or risk) on FMD, adhesion molecules and adiponectin, was there anything else they measured that did have significance and is worthy of our time to look at?

How about we take a look?

Two groups of subjects were randomized into two different dietary protocols - the first included 13 people assigned a low-carbohydrate diet (40% protein, 27% carbohydrate and 33% fat; 26g fiber daily); the second included 12 people assigned the high-carb diet (20% protein, 60% carbohydrate, 20% fat; 40g fiber daily).

Both groups were weighed, measured, poked and prodded and followed up with a 6-weeks, 12-weeks and 52-weeks. Measurements and testing included weight, BMI, blood pressure, cholesterol, glucose, insulin, CRP, VCAM1, sICAM1, E-selectin, P-selectin, and total adiponectin. In addition, vascular measurements were taken for blood pressure analysis and endothelium-dependent FMD, along with an assortment of other tests.

The various measurements were duly recorded for baseline and re-measured during follow-ups, and were included in the final paper. Some critically important measures were statistically significant, but not the focus of the study design; thus not highlighted in the abstract conclusions.

We hear a lot about how low-carb diets are bad for cholesterol.

In this study, like others, total cholesterol, LDL and triglycerides were lowered over the course of the year and HDL rose while following the low-carb diet.

Total Cholesterol:
Baseline = 5.3
52-weeks = 4.62
[low-fat group went from 5.7 to 4.94]

LDL:
Baseline = 3.5
52-weeks = 2.69
[low-fat group went from 3.8 to 3.07]

HDL:
Baseline = 1.3
52-weeks = 1.44
[low-fat group went from 1.3 to 1.34]

Triglycerides:
Baseline = 1.7
52-weeks = 1.07
[low-fat group went from 1.4 to 1.34]

Intriguing too was the improvements with glucose and insulin following the low-carb diet:

Glucose (fasting):
Baseline = 5.9
52-weeks = 5.19
[low-fat group went from 5.8 to 5.5]

Insulin (fasting):
Baseline = 16.9
52-weeks = 7.28
[low-fat group went from 12.1 to 5.22]

An interesting finding was that adiponectin, a hormone involved in a number of metabolic processes, including glucose regulation and fatty acid catabolism, "did not change significantly after 12 weeks of weight loss" (p=0.10), but increased (good) at the last measurement, 52-weeks, at the end of the study (p=0.05).

Blood pressure (not high at baseline) improved, from 122/75 at baseline to 115/68 at the 52-week measure; for those on the low-fat diet, blood pressure increased from 122/75 at baseline to 130/74 at 52-weeks.

It's clear in the data that both dietary approaches offered improvements with weight loss in the above measures of risk factors. Something though wasn't "right" to help with, improve, endothelial-dependent FMD. We'll explore potentials in a moment.

Somethign troubling that seems glossed over - the higher blood pressure in those following the low-fat diet - where at baseline their blood pressure averaged 122/75, at 6-weeks it improved to 115/72 and again improved at 12-weeks was similar at 118/70. What happened between the 12-week measure and the blood pressure reading at week 52, when blood pressure was now averaging 130/74?

This is something I would consider worthy of noting, even maybe point out and suggesting additional questions and investigation as to why!

In the discussion section, the researchers stated that "The main finding of the present study was that weight loss on a low-carbohydrate diet which brought about reductions in glucose, insulin and LDL-C did not improve FMD either after short-term weight loss or long-term weight maintenance. Irrespective of diet composition weight loss had beneficial effects in the short term on adhesion molecules and blood pressure and in the longer term on adiponectin and P-selectin. There appears to be a delay in improvement in both adiponectina nd P-selection as these molecules did not improve until weight loss had been maintained for a year."

They went on to add, "Lack of change in FMD in the present study confirms our previous finding that weight loss does not improve FMD...One of our goals with the dietary intervetion was a reduction in LDL-C which we achieves, 18% at 6-weeks and nearly 30% at the end of the study with no effect on FMD."

The researchers also noted that "The present study was also designed to achive a reduction in glucose in a 6-week weight loss intervention on a more moderate diet of 6000kJ and we achieved this but with no effect on FMD."

And, "A complex physiological response such as FMD may be related to LDL and glucose cross-sectionally and in post hoc analyses but these may not be casually related but correlate in some circumstances with the real unmeasured mediator of change. For instance, oxidative stress may be a major factor in reducing NO bioactivity but reducing LDL levels may have no effect on this even though the endothielial cell is clearly heathier as judged by a reduced adhesion molecules."

In the end, they concluded that "weight loss on a low-carbohydrate, low-saturated fat diet, does not improve FMD despite improvement in cardiovascular risk factors. The improvement in adiponectin was delayed."

So what was their error of omission?

Well, for one they failed to note the problematic rise in blood pressure observed in the subjects following the low-fat diet. But, let's set that aside for a moment.

They also failed to note that the above failure to improve FMD was also observed in subjects following the low-fat diet; one that happened to be designed well enough to match the American Heart Association recommendations!

Yet even that low-fat diet (20% of calories from fat) didn't help improve FMD, despite their weight loss, improvement in glucose, insulin and cholesterol; but this was left unsaid.

I'm not surprised.

So, what we're left with is the stated null finding of those on the low-carb diet, with no real statement that neither dietary approach did much for FMD.

I hate to say it, but there was also a lack of curiosity as to why this was.

It's pretty much accepted dogma that a low-fat diet improves the cardiovascular system, thus would exert a postive - significant - effect on endothelial-dependent FMD. It didn't, yet the researchers didn't say "hey, wait, this low-fat diet didn't help either" and instead highlighted that the low-carb diet didn't improve FMD in their conclusions.

Some questions really do need to be asked.

First, how did the low-carb diet look compared with the habitual diet?

We know subjects were consuming, on average, 11.4mJ each day (2725-calories) as their habitual diet. The weight loss diet was 6000kJ each day (1430-calories). They followed the weight loss phase of the diet for six weeks and lost 5.8kg, or 12.75-pounds.

Let's do math!

Each day, we're to believe, the subjects were in a calorie deficit of 1295-calories. Six weeks is 42-days, so over the period, a calorie deficit of 54,390 calories - enough to theoretically lose 15.5-pounds. Hmmm....Okay, so it's pretty clear they did not really follow the diet as planned, since it's clear they consumed more calories than was reported. Happens all the time, no biggie.

Except, we have no idea what the excess calories were, so we have a confounding variable here. Did they eat pie? Did they eat broccoli? Did they eat fatty meat instead of lean meat? Did they skip the oatmeal and eat eggs? Who knows?

It's also noteworthy that the low-fat dieters ate a habitual diet of 10.8mJ daily (2581-calories) and were placed on the same weight loss calorie level. So they were in a calorie deficit of 1150-calories each day, or a six week deficit of 48,342-calories. This theoretically would result in a weight loss of 13.8-pounds; they lost 5.9kg (13-pounds). Did they cheat less? Did they stick to the diet more carefully? Who knows?

But, we can be sure we have a confounding variable here - something doesn't add up, and it looks like that something is calorie intake. It appears it was higher than the dietary protocol called for; and an increased calorie intake we have no idea what foods/macronutrients it came from.

So then, is there anything else? Let's see how macronutrient intake changed on the low-carb diet.

At baseline, their habitual diet - 2725-calories - was from 39.6% carbohydrate (270g), 19.6% protein (133.5g) and 36.5% fat (110.5g). We do not know the baseline intake for fatty acids, but do know the dietary protocol was strict - saturated fat 7%, PUFA 6% and MUFA 13% of calories.So, while following the weight loss diet, the macronutrient profile changed to provide 1430-calories each day, of which 33% were carbohydrate (118g), 40% protein (143g) and 27% fat (43g) with 7% from saturated fat (11.1g), 6% from polyunsaturated fat (9.5g) and 13% from monounsaturated fat (20.7g).

The first glaring disparity is the protein-to-fat intake, for every 1g of fat, they were expected to consume 3.3g of protein; this is a highly unusual pattern, heavy with protein and too lean - if you review other studies on "low-carb" diets, the fat intake is usually higher than the level in this protocol and protein typically lower; of note, this intake ratio is next to impossible without some funky planning. I'd like to know how much soy was a part of this diet? How much of the diet was comprised of non-fat dairy? How much fish was allowed, and what type was it? Were protein shakes or supplements part of the protocol? If so, which type of isolate dominated?

Without this specific data, it's difficult to say one way or another if the foods included may have contributed to the null finding or not.

So here, we have a potential confounding variable that is unexplored.

Anything else?

Well, from the data we do know, it seems we find an inadequate level of polyunsaturated fats - with just 9.5g each day; a level at which the subjects are unable to meet essential requirements for omega-6 or omega-3 fatty acids!

I am really starting to wonder why researchers designing diet protocols that are inadequate for known essential nutrients?

The Institute of Medicine (IOM) clearly states in the Daily Recommended Intake documentation, the MINIMUM required each day from omega-6 is 5% to 10% of calories and the MINIMUM requirement each day from omega-3 is 0.5% to 1% - when calories are adequate to maintain weight. In absolute terms - absolute gram minimums - the IOM states that adequate intake of omega-6 fatty acid is 14g-17g for men (depending on age) and 11g-12g for women (depending on age); and that adequate intake of omega-3 fatty acids is 1.6g for men and 1.1g for women.

Combined, the absolute minimum intake for essential fatty acids is between 15.6g-17.6g for men and 12.1g-13.1g for women.

In this study, even if every last gram of polyunsaturated fat was an omega-3 or omega-6, these subjects were deficient for essential fatty acids with only 9.5g of polyunsaturated fats as part of the diet.

So, again, confounding variable - huge confounding variable!

And the researchers question why the diet didn't have an effect on FMD?

Perhaps the researchers haven't read the data showing improvement in cardiovascular health when essential fatty acid intake is optimized to meet or exceed current recommendations?

Recent evidence of the role of omega-3 polyunsaturated fatty acids on blood pressure control and hypertension-related complications

Omega-3 Fatty Acids: Role in Cardiovascular Health and Disease

Fish Oil and Endothelial Function

I can't say it enough - I love good data, but studies like this, with macronutrient intakes, as percentage of calories, is highly confounded data. Designing a dietary approach to lose weight or maintain weight, macronutrient percentages are often inefficient and do not meet essential nutrient requirements.

I'd really like to see some researchers start designing studies to ensure adequate intake of essential nutrients within the calorie deficits - until we start to look at the nutrient-quality of weight loss diets, I'm afraid we're not going to make much progress to provide the public with sound, scientifically supported recommendations.

Tuesday, May 22, 2007

The Devil in the Details - Low-Carb High Protein Diet Kills

A study - Low-carbohydrate–high-protein diet and long-term survival in a general population cohort - published in the May edition of the European Journal of Clinical Nutrition (originally available ahead of print, November 2006), concluded that "Prolonged consumption of diets low in carbohydrates and high in protein is associated with an increase in total mortality."

When I read the first publication of the study, back in November, I decided not to write about it since I was focused on penning articles about diabetes throughout National Diabetes Month and this study wasn't about diabetes. It remained on my pile of studies to consider, but as time passed, it seemed less and less important to write about. Now, with it hitting the print edition, and a renewed interest in the findings, it's time to take a look at what the researchers found and how they reached their conclusions.

Jake Young, who writes at Pure Pedantry, thought it worthwhile to take a look too. In summing up the design of the study, he wrote "[j]ust to cross the t's and dot the i's, they also control sex, age, years of schooling, smoking, BMI, physical activity, ethanol intake, and (in the data I am going to talk about) energy intake;" thinking, I believe, that adjusting for these confounding variables leads to higher quality conclusions.

Except in this case, adjusting for some of these variables led to a leap-of-faith extrapolation from the data because without making adjustments there was no significant finding to speak of, "[i]n model 2, the LC/HP score (absolute values) was positively associated with mortality, although the association did not reach statistical significance (P=0.14)." [emphasis mine]

In other words the association was statistically due to chance and therefore a null finding.

But, let's not let that get in the way of a good chance to find statistic significance!

Rather than take the data at face value for absolute intake (what people were eating), the researchers decided to adjust energy intake and considered this adjustment "as they should be, isocaloric..." to show how, after adjusting for energy intake variables things change.

And change they did.

With this one adjustment, statistical significance magically appears and now "mortality was significantly associated with reduction of energy-adjusted carbohydrate intake and nonsignificantly with increasing protein intake."

But still, how exactly to find protein problematic?

Ah, one more adjustment just might do it.

The researchers noted that their "model 3" "does not specify the complementary changes that have to be introduced for the preservation of total energy intake, when carbohydrates and proteins change." So, they created "model 4" and said it was "the most appropriate" since it was both isocaloric (adjusted for energy intake) and now adjusted to reflect changes from less carbohydrate and more protein.

Viola!

"In this model, increasing LC/HP score was significantly associated with mortality (P=0.001)."

Except, no one in the cohort ate like the adjusted diet, the statistically significant findings are not from real people eating real food (absolute intake), but are only found upon adjustment of energy and intake from protein and carbohydrate. The researchers justified this adjustment as necessary with "[i]ndeed, many of contemporary public health policies rely on extrapolations, so that if something is detrimental at a certain exposure level, its effect is likely to be more detrimental at a more extreme level."

Perhaps this is part of the problem with our public health policy? We're basing recommendations on extremes, extrapolated from adjusted models, rather than real world eating habits.

This is how the American Heart Association comes up with recommending less than 7% saturated fat to all Americans, even those at low risk for heart disease; they take data from studies that found no benefit from reducing saturated fat to 10% or less of calories and do the mental gymnastics to leap to an idea that benefit will be seen when saturated fat is less than 7% of calories. No data, just pure extrapolation and wishful thinking.

But, I digress...

There'd be nothing to talk about with this study if the researchers only went with their cohort and their habitual diet. Remember, when the absolute intake data was crunched, there was no statistically significant finding.

It's only after the researchers play with the data and make adjustments - adjustments outside the "norm" of their population cohort - into the extreme models, that they find significance.

In the real world you'll be hard pressed to find someone eating a diet within the extreme models they created. That's because the fundamental flaw in their model adjustment was the belief that decreasing carbohydrate means increasing protein. As the researchers noted in their paper, their adjustment model "relies on opposite changes of two nutrients with equivalent energy values and tends to be unrelated to total energy intake."

Simply put, the assumption was that reduction of carbohydrate translates to an isocaloric increase in protein.

The problem with this is that in the real world, increasing protein beyond what the body needs is extremely difficult due to satiety hormones that effectively shut down hunger when protein intake is adequate and carbohydrate is restricted. So the idea that one is effectively replacing carbohydrate with protein has a limit. A limit that seems beyond the grasp of this research group, who didn't seem to ask the important question - why did those with higher LC/HP (low-carb/high-protein) scores consume less calories than those eating a higher carbohydrate diet?

Rather than delve into this, they adjusted protein as if this group could and would consume more calories and more protein in a linear progression, adjusted their habitual intake to reach an isocaloric level comparable with their higher carboydrate counter-parts. But, because protein is such a sating macronutrient, this adjustment is not based on reality, but is purely hypothetical; and a hypothetical situation that one is likely to find impossible in a real world eating situation.

My take - the researchers would have been better off publishing their findings from the absolute intake data and letting the data stand as it is rather than make various adjustments to convoluted extremes and try to make headlines. Nice try though.

Wednesday, May 02, 2007

Diet for Diabetes Mired in Half-Truths

"A half-truth is a whole lie."
Yiddish Proverb

If you want to see a truly stupendous exercise in smoke-and-mirrors and misdirection, look no further than people like Hope Warshaw, or organizations like the American Diabetes Association -- they've practically cornered the market on rhetorical tricks and red herrings.

Of course, that's almost understandable since everything recent scientific studies have to say about their most popular punching bag, carbohydrate restricted diets, directly contradicts their doom-and-gloom predictions that no one can eat that way, or should.

Case in point, the recent Diabetes Health article penned by, none other than, Hope Warshaw, The Optimal Eating Plan for Type 2 Diabetes?

Let me first say, Ms. Warshaw is quite proud of her accomplishments and offers visitors to her website the following information in her biography detailing her direct work with "McNeil Nutritionals, LLC, a Johnson & Johnson Company; Mead Johnson Nutritionals, a division of Bristol-Myers Squibb; Roche Diagnostics and Novo-Nordisk Pharmaceuticals. She writes consumer and professional materials for brochures, newsletters and websites. Hope has worked with PR [public relations] companies on nutrition-related campaigns, such as Barkley Evergreen & Partners, Fleischman Hillard, Inc., Paine PR, Edelman, RF Binder and Hunter Public Relations."

I point this out to highlight the fact that Ms. Warshaw is well schooled in media and marketing, or should I say "spin"? Simply put, she's no novice when it comes to creative persuasion, that is how to craft a message that hits on all cylinders of your emotions.

Keep in mind as we move on, feelings do not change facts.

In her recent addition to the media fodder attempting to discredit carbohydrate restricted diets, she sets the stage quite brillantly to avoid fact by littering her piece with half-truths designed to appeal to fear.

Bottom line - statements with half-truths are deceptive; they're partly true, but not the whole truth; they present a verifiable piece of information that is true, but in context is not representative of the truth. Some might say they're lies, others might say they're stretching the truth, and still others may say that a half-truth is really just being economical with the truth.

They've been with us for generations. We find them littering food packaging and in advertisements for many different things; sometimes stated, sometimes implied, and sometimes even admitted to in the fine print no one reads. Half-truths are so prevalent in our daily lives, is it any wonder that when one appears in an article about health, no one seems to notice?

Ms. Warshaw sets the stage by setting readers minds to believe her article is the truth about the "optimal" diet for those with diabetes; and uses a number of literary tricks - rhetorical statements, imaginative prose and pursuasive words to trigger a desired response in readers. She leads with our base knowledge that dieting is hard and we should "be realistic and take a long-term perspective in this “which diet is best” debate, rather than wasting time quibbling over extremes - from low-carb to vegan."

With this one sentence she's already working hard to influence readers by bringing them into her world while employing empathy, *we all know* it's a waste of time to quibble over diet, that vegan and low-carb are *extreme* diets, and that, as the title of her article hints, *we know* the optimal diet for those with diabetes.

Forget about data, there isn't even room for debate.

Since that isn't quite enough, she then adds a message driver, a logical fallacy to drive this message home by appealing to fear, one of our strongest emotions.

Fear of being a loser, on the losing team, on the team that no one wants to be a part of anyway, the team that everyone quits because it's so bad.

"A Team’s No Good If All the Players Quit"

Think about that statement for a moment.

A Team’s No Good If All the Players Quit.

It conjures up cliches we all know - quitters never win, be a team player, teamwork works, winners never quit...and it stirs up fear - the fear of failure.

So with that in play, she then moves in with the half-truths - "A number of studies that compare low carb diets to conventional diets demonstrate early initial weight loss and improvement in other health parameters, such as blood glucose control. But studies of low carb diets that last longer than six months do not show significantly more weight loss. They do show that many study subjects drop out of the study and are unable to stick with the diet."

She cites two studies to support her assertion and show veracity of her statements:

1. Foster GD, Wyatt HR, Hill JO, McGuckin BG, Brill D, Mohammed S, Szapary PO, Rader DJ, Edman JS, Klein S.: A randomized trial of a low-carbohydrate diet for obesity. NEJM 348(21): 2082-90, 2003.

2. Bravata, DM, Sanders L, Kuang J, Krumholz HM, Olkin I, Gardner CD, Bravata D: Efficacy and safety of low-carbohydrate diets: a systematic review. JAMA 289: 1137 – 1850, 2003.

When we review these studies, we find her statements are accurate, but more accurately they are smoke and mirrors because they do not present the whole truth since the two studies are not trials specifically investigating dietary approaches for those with diabetes.

Indeed the studies she cites - one is an investigation comparing low-carb and low-fat diets for obesity, the second is a meta-analysis reviewing some of the published studies up to one year comparing low-carb and low-fat diets for obesity. So while weight loss was a key part of the studies cited, they are not the most relevant available to us to examine for those with diabetes.

You see, the two studies above, while they included subjects who were obese, they were not diabetic subjects; and the second was not a research study, but a meta-analysis review of studies that included the first study cited.

But a casual reader wouldn't know that - they only see two references which lends credibility to her statements and makes them appear to be important in determining dietary recommendations for those with diabetes.

Now consider this - how would her statement need to change if she included Beneficial effects of ketogenic diet in obese diabetic subjects?

In this study, subjects with and without diabetes, were grouped by blood sugar levels and the study lasted 56-weeks (one year, one month) and there were no drop outs - that is all who started the study completed it. With across the board improvements in total cholesterol, HDL, LDL, triglycerides, and fasting blood sugar in both groups, along with significant weight loss over the period of a year (a 54-pound average weight loss for both groups!) is it any wonder she didn't cite this one?

Or how about Low-carbohydrate diet in type 2 diabetes. Stable improvement of bodyweight and glycemic control during 22 months follow-up, a study over a period of almost two years that compared a low-fat diet to a low-carb diet in those with diabetes; and at six months, those following the low-fat diet abandon it when they saw the results of those following the low-carb diet? Oh, yeah, there were also significant improvements to risk factors including blood sugars (with elimination of medications) and weight loss and weight maintenance.

Two longer term studies, both ignored for this particular article. But a casual reader doesn't know they exist and Ms. Warshaw isn't going to tell.

So she moves on to the statement "Low-carbohydrate diets are not recommended by the American Diabetes Association for two key reasons. First, avoiding carbohydrate, as some low carb diets suggest, does not entirely return blood glucose levels to the normal range after meals. Second, an adequate amount of carbohydrate is an important component of a healthy eating plan, providing essential fuel, vitamins, minerals, and fiber;" and offers two more citations to support her words, both references are ADA statements.

So again we find half-truth, but not the whole truth.

This is because Warshaw sees the world though the prism of ADA truth making it impossible to take her seriously on any level.

Does she really believe someone with diabetes will not, or more accurately, can not give up consuming sugar or excessive carbohydrate that she feels it necessary to portray the dietary approach as one where "avoiding carbohydrate" is a problem rather than the solution?

Many, if not all, carbohydrate controlled plans restrict total carbohydrate each day, but no plan says you must avoid all carbohydrate or eliminate it completely. Maybe she has a problem with a diabetic avoiding sugar and foods that quickly raise blood glucose?

Second, her statement that avoiding carbohydrate..."does not entirely return blood glucose levels to the normal range after meals" implies that what she's going to present to readers will do just that - just ignore the smoke, just ignore the mirrors, as she continues with "an adequate amount of carbohydrate is an important component of a healthy eating plan, providing essential fuel, vitamins, minerals, and fiber."

Ignore the fact that all carbohydrate restricted plans include and encourage a high intake of non-starchy vegetables (rich with nutrients, fiber and minerals); no the message by now is clear - low-carbohydrate diets are for losers, they're unhealthy, nutrient deficient, make you avoid something with no reward for the effort (normal blood sugars after meals) and you're not going to lose weight with a low-carb diet anyway, move along now and don't pay to much attention to the fact she opened with two "extremes" low-carb and vegan but only attempts to discredit one.

Afterall we can't have anyone consider a low-carb diet, because "diets that force people to dramatically change their eating style are not maintained over the long haul. These diets require too dramatic change compared to the common, albeit not healthy, eating habits of the 21st century."

Take a good look at the last sentence - it's too big a change from the "unhealthy" eating habits we have, but by golly, a person with diabetes deserves to eat whatever they want and they can continue on with their common ways!

What she is saying is that no person with diabetes is willing to change their unhealthy ways, so why bother.

She then has the nerve to present to readers more rubbish - "Research from numerous studies, including the Diabetes Prevention Program and the National Weight Control Registry, show that people can lose weight and keep it off successfully for three years and five years, respectively, by reducing dietary fat and total calories."

Two is not "numerous" it's a couple.

And one is from subjects at risk for diabetes, the other a self-selected group of dieters who are followed in a national database because they lost weight not because they have diabetes and are in good glycemic control and maintaining weight loss!

Ms. Warshaw is pretty confident you won't check or think critically, and that you'll take her half-truths and believe a low-carb diet is impossible to follow for the long-term.

She's so sure of this in fact, she has no worry saying you can't diet on your own anyway - you need help, "you need knowledge and skills to make lifestyle changes, as well as help in setting behavioral goals, not to mention ongoing and long-term support...Ask your health care provider to refer you to a diabetes education program."

Her writing is chock-full of manufactured criticism, dead-wrong assumptions, half-truth evidence, and child-like ignorance of the emotional universe inhabited by men and women with diabetes.

She hopes no one notices that what is more important is the quality of pertinent research published, not the crafty presentation.

She relies heavily on logical fallacies - appeal to authority (the ADA) and appeal to fear - to grab and hold readers' attention, then offers clever cliches to play emotions without presenting pertinent facts to help an individual with diabetes understand the hard data.

The truth is modifying your diet is difficult, losing weight may be hard, and maintaining weight after it's lost can be a challenge; having diabetes is also a challenge and managing everything that comes with a diagnosis is no small endeavor - everything from blood glucose levels to HbA1c to cholesterol to body weight is monitored, tracked and managed; not for a week or a month, but for the rest of your life.

Ms. Warshaw contends that modifying diet too is too much to ask, too much for a person to do, too much for anyone to have to do over the long-term.

She offers the status quo - the ADA position that one deserves to be able to eat normally (even though she admits this "normal" is unhealthy); afterall a low-carb diet requires "too dramatic change" in eating habits.

Notice she hasn't said a word about the dramatic change one must make to include their medication each day; self-monitor blood sugar levels; keep doctor, opthamologist and podiatrist appointments; adjust medications as complications arise; injecting insulin each day; careful wound care; and more.

Notice she hasn't said a word about what dietary modification is necessary with the ADA recommendations.

Notice she presents no evidence to support the implication that normal blood sugars are achieved when one follows this "optimal diet."

That's because normal blood sugars do not happen when one follows the dietary recommendations of the ADA.

In fact, the ADA position is that medication is the first line defense upon diagnosis because their dietary approach fails over the long-term.

Oh, Ms. Warshaw didn't include that, did she?

No, she's done a run-around the evidence, fully aware the casual reader won't know the published data well enough to spot her half-truths or question the depth of her statements.

She stays on the surface rather than digging deep and offering a compelling look at the truth.

The truth is, those with diabetes deserve to know they have options.

They deserve a full disclosure of the data to allow them to make an educated decision about what they can and cannot do with diet; what they will and will not do to manage their diabetes.

They deserve to know that not only do blood sugars normalize in many with diabetes who adhere to a carbohydrate restricted diet, but medication is often eliminated or reduced.

They deserve to know a dietary approach is available that may indeed provide normal blood sugars!

They deserve no less than full patient autonomy, something Ms. Warshaw seems to know nothing about.

They deserve the whole truth!

Tuesday, April 24, 2007

Weight Loss, Cholesterol and Blood Sugar Improvements - What's the Wonder Drug Now?

While the media is hot and heavy to lead their headlines with junk science complete with amateurish conclusions, a study was quietly published Friday in the journal, Molecular and Cellular Biochemistry - Beneficial effects of ketogenic diet in obese diabetic subjects (abstract) - that's remains ignored.

No fanfare, no ballyhoo, in fact, not one headline to call attention to the significant findings, over the course of a year, of a dietary trial in obese subjects with and without type II diabetes.

Findings that included:

For both groups, diabetic and normal glucose:
  • Weight loss of 24.55kg in 56-weeks (that's 54-pounds)
  • Total Cholesterol down 19.3%
  • LDL down 28.2%
  • HDL up 52.3%
  • Triglycerides down 59%
  • Fasting Blood Glucose down 31%

For those with type II diabetes:

  • Weigth loss of 24.4kg in 56-weeks (that's 53.7-pounds)
  • Total Cholesterol down 28.5%
  • LDL down 33%
  • HDL up 63.4%
  • Triglycerides down 40.8%
  • Fasting Blood Glucose down 50.9% (yes, glucose fell more than 50%)

So, what exactly did the researchers have these subjects do that led to such impressive improvements over the course of 56-weeks?

Sixty-four subjects were divided into two groups - thirty one had abnormal glucose levels (type II diabetes) and the remaining thirty-three had normal glucose levels. Both groups were instructed to modify their diet to include only 20g of carbohydrate a day from a list of foods allowed along with 5-tablespoons of olive oil on salads, and allowed 80g-100g of protein from meat, eggs, fish, poultry and full-fat cheese each day. No alcohol was consumed by participants. At week 12, participants were allowed to increase carbohydrate to 40g per day. Throughout the 56-weeks some foods were forbidden - flour, bread, rice, macaroni, noodles, honey, sugar, sweets, cakes, potatoes, all fruit juices and all soft drinks.

Yes, shocker - the study was designed to measure the effects of a ketogenic diet in subjects with and without type II diabetes.

So, with the above findings, it's no wonder this one is being quietly ignored.

While the media, government policy makers and leading health organizations keep wishing for negative findings from studies of low carbohydrate diets, the opposite keeps happening - the pile of studies finding significant improvement keeps growing higher and higher.

How profound were the changes in real numbers?

Those with diabetes had baseline fasting blood glucose levels of 188.64mg/dl; by the end of the trial, at week 56, their fasting blood glucose averaged 87.66mg/dl. Even those with normal blood glucose, who started with a baseline fasting blood glucose of 92mg/dl, saw improvement; at the end of the trial they had a fasting blood glucose of 85mg/dl.

There is not one drug on the market today, recommended for those with diabetes, that shows such significant improvement in fasting blood sugar, sustained over a period of more than a year!

Oh, but it gets better. Cholesterol improvements in this trial were unmatched by any drug trial.

Those with diabetes:

Baseline Week-56

Total Cholesterol 265 190
LDL 203 131
HDL 39 62
Triglycerides 418 89

Those with normal glucose:

Baseline Week-56

Total Cholesterol 214 181
LDL 156 109
HDL 47 63
Triglycerides 160 77

No cholesterol medication reduces LDL by 33% while also increasing HDL by 63.4%; and reducing triglycerides by 59%.

If the above finding were for a new drug, not only would the headlines be screaming for everyone with dyslipidemia to be prescribed it immediately, but every last expert in the country would be making the rounds in the media to be heard about this new wonder drug!

Sadly this isn't a new wonder drug rich with potential for profits. Instead it's simple dietary therapy, with no bottomline enhancement for anyone, save for a few farmers and ranchers.

So no headlines, no urgent call to take a look at the data which validates previous studies, no demands for reviewing the evidence; nope, the powers that be will continue along, fingers in ears, singing "La La La" as they hope no one notices the mountain of evidence growing.

If you have diabetes, or are at risk for developing diabetes, get to know what a carbohydrate restricted diet is and how to integrate it into your health management, it may save your life.

UPDATE 4/24/2007

A reader brought to my attention a pretty glaring error in reporting of reduction of triglycerides. I posted the numbers from the full-text above as published - a reduction in triglycerides in those with high blood glucose = -40.8%

A review of the actual numbers shows a reduction over the 56-week period from 4.681mmol/l to 1.006mmol/l - a 78.72% reduction in those with high blood glucose; and from 1.827mmol/l to 0.861mmol/l in those with normal blood glucose - a 54.01% reduction.

Monday, March 26, 2007

Atkins Editorial Rejected

Five heathcare professionals - Dr. Stephen D. Phinney, MD; Dr. Mary C. Vernon, MD; Dr. Eric C. Westman, MD; Dr. Jay Wortman, MD; and Jacqueline A. Eberstein, RN - recently penned and submitted an editorial response to the recent media attention concerning the A to Z study published in JAMA. It was rejected by JAMA, Newsweek, Time and others. Here it is, in its entirety:

More Science and Less Zealotry, Please.

The controversy over which diet is best for all has again made headlines with the publication of the Stanford University study in the Journal of the America Medical Association March 7, 2007. Since the results are favorable to the low-carbohydrate Atkins diet, the usual criticism can be expected to follow.

Predictably, Dean Ornish has launched a tirade in which he manipulates the study findings to find fault with the low-carb approach and to deflect criticism away from his ultra low-fat diet which did not perform well in the study. Unfortunately, this is an argument based on dogma and not on science. The science speaks for itself.

As scientists and clinicians, we believe that no one dietary approach is going to be ideal for everyone. There is no doubt that, for some, an ultra-low-fat approach may be appropriate. Unlike Dr. Ornish, we recognize that there is no one-size-fits-all approach to the enormously complex problem of obesity and related conditions. Unfortunately, other authoritative sources like the US dietary guidelines also recommend a single lowered fat high-carbohydrate diet approach and have been doing so over the decades that this epidemic has grown.

Gratuitous attacks on the Atkins diet that imply it involves abandonment of wholesome vegetables and fruit for “bacon and brie” are simply wrong. Even in the most restrictive phase it meets the recommended daily guidelines for vegetables and fruits. As one advances through the phases, low-glycemic fruits, more vegetables, legumes and even whole grains are introduced based on an individual’s metabolic tolerance for these foods. One survey found that people who follow the Atkins plan over the long term eat more vegetables than they did before. Another study found that rather than increase the intake of fat and protein to compensate when carbohydrates were reduced, people simply ate less.

The unfortunate reality of today is that too many Americans are eating potato chips and fries and drinking sugar-sweetened beverages. We support the idea that wholesome foods such as meat, fish, cheese and eggs along with vegetables and low glycemic fruits constitute a healthier diet than chips and fries and sodas.

While this study examined four popular dietary approaches, what is clear is that whatever approach one takes to healthy eating, success will depend on how well you can stick to it. In this case, and in many earlier studies, it is clear that the Atkins diet is the one most people can maintain. On the other hand, the extremely low-fat diet advocated by Dr. Ornish is very difficult to follow. In this study, the subjects who were supposed to reduce their fat intake to his recommended intake of 10% could not reach that target.

Another important aspect of this and earlier studies is the beneficial effect that reducing carbohydrates has on metabolic markers. In his criticism, Dr. Ornish states that the LDL-cholesterol level fell in response to his diet, but does not mention that none of the differences in LDL-C in this study were statistically significant. This is therefore not a scientifically valid criticism. On the other hand, it is widely recognized that elevating the HDL-C, the good cholesterol, is an important factor in reducing cardiovascular risk. In this study there was a highly significant 10% rise in HDL-C in the Atkins group but no such change among those who followed the very high-carbohydrate Ornish diet.

In the same vein, the Atkins group demonstrated a significant (both statistically and clinically) greater reduction in systolic and diastolic blood pressure than the other three diets. A difference in mean arterial pressure of 5 mm Hg is about the response we would expect to see with a first-line pharmaceutical in the clinical setting. Any objective observer would acknowledge this as a major beneficial effect of the Atkins diet.

Dr. Ornish suggests that the positive findings of research such as this that supports the Atkins diet will cause problems, and that “many people may go on a diet that harms them based on inaccurate information.” This is a wildly irresponsible statement, given the consistency with which a reduction in important metabolic and cardiovascular risks are achieved by lowering carbohydrate consumption. It is simply preposterous to suggest that an approach that leads to significant risk factor reduction is unhealthy.

The seriousness of the accelerating epidemic compels us to think outside the box to find new solutions where the status quo has failed. The only approach that will be successful is one that people can actually follow. This study adds to the mounting evidence that the Atkins diet is a healthy choice which should be supported as a viable way to lose weight and improve metabolic and cardiovascular risk factors.

The Real Atkins Lifestyle

Before there was research on the Atkins diet it was commonly criticized in the belief that it would elevate cholesterol, ruin one’s kidneys and bones and cause heart disease. None of this has been borne out by the research.

What is clear from this JAMA study, and others like it, is that cardiovascular risk factors actually improve when controlling carbs. The scientific studies of this approach have shown numerous times that a pattern of rising HDL-C and falling triglycerides is the hallmark of carb restriction and that this benefit occurs even in the absence of weight loss.

Research also shows that rising HDL-C (good cholesterol) and falling triglycerides is correlated with larger LDL-C particles which are less likely to cause heart disease. Even the much touted statin drugs do not deliver this kind of improvement in LDL-C particle size. On the other hand, the research shows that eating a high-carb diet and cutting fat intake results in small dense LDL-C particles that are linked to an increased risk of heart disease.

Importance of Fat

There are other problems associated with extremely low fat diets, as well. Cutting fat intake can lead to deficiencies in fat soluble vitamins, depletion of essential fats such as EPA and DHA, and decreases in the absorption of nutrients. Studies also show that people with cholesterol levels that are too low become prone to depression, suicide and cancer and have higher overall death rates than those who have higher cholesterol levels.

When all is said and done, it behooves us to remember that the diet debate is not a horse race where there is only one winner. We know there is a great variability in metabolic and genetic factors that will determine what dietary approach is best for each individual person. Although, in this and many other studies the Atkins diet worked better for more people, it is also evident that other dietary approaches will work for some people as well. The most important thing we have learned from dietary research is that people need to find the approach that will deliver healthy outcomes for them individually. And, just as the proof of the pudding is in the eating, the proof of a diet's effectiveness is whether it can sustain those benefits over the long haul. Hopefully, the weight of the evidence will now allow the Atkins diet to be recognized and supported as a legitimate option for people who want to improve their health through better nutrition.

On a final note, Dr. Ornish’s repugnant attempt to undermine Dr. Atkins’ credibility by perpetuating the myth that he had heart disease is unconscionable. It is unbecoming of any honorable person to make ad hominem attacks on those who are departed. Enough is enough. Dr. Atkins died of a head injury. He is no longer with us, but the line of scientific inquiry that he started continues to vindicate his dietary approach. And no amount of unfounded criticism will alter the fact that this study, and the 60 others before it, clearly demonstrate that what Dr. Atkins had been telling us all along was right.
  • Jacqueline A. Eberstein, R.N. Co-author, Atkins Diabetes Revolution, President, Controlled Carbohydrate Nutrition
  • Stephen D. Phinney, M.D. Ph.D Emeritus Professor, Department of Medicine, UC Davis, Elk Grove, Cal
  • Mary C. Vernon, M.D., CMD, Co-author, Atkins Diabetes Revolution, President, American Society of Bariatric Physicians
  • Eric C. Westman, M.D. M.H.S, Associate Professor of Medicine, Duke University Medical Center
  • Jay Wortman, M.D, Department of Health Care & Epidemiology, Faculty of Medicine, University of British Columbia