Wednesday, February 01, 2006

Getting the Calorie Intake Right for Weight Loss

Some people actually make a conscious choice to permanently restrict their calorie intake below their Active Metabolic Rate (AMR) in the hope it will increase their chance to live longer. Such an approach is always based on a very nutrient-dense diet - those following this type of diet pay particular attention to the micronutrients and essential fatty acids & amino acids required each day while carefully controlling their calorie intake.

I personally am not convinced such an approach will increase longevity because of the calorie restriction. I am, however, open to the idea that such an approach can increase lifespan due to the nutrient-rich nature such a dietary lifestyle demands.

But, I'm not writing about this approach today because of the potential longevity...nope, today we're going to take a look at what happens when someone cuts calories over a long period of time. Specifically, how their weight loss stops!

The Post-Gazette today republished an article from the Wall Street Journal - Health Journal: The science behind starvation diets - that provides an overview of this dietary approach. Within the article is something of interest to anyone considering various diets for weight loss:

More-serious calorie restrictors reduce their daily caloric intake by as much as 40 percent. For instance, a six-foot, moderately active, 180-pound man normally would eat about 2,640 calories a day. If he practices calorie restriction, his daily calories could drop to just 2,370 or all the way down to about 1,585. Although people who practice calorie restriction, typically lose weight at first, eventually their body and metabolism adjust and the weight loss stops, despite the low calorie level.

Read that last sentence again! Eventually their body and metabolism adjust and the weight loss stops, despite the low calorie level.

Now how many times have I said this?

I bring it up again because the message you hear from the weight loss "experts" remains to "eat less and move more," even in the face of mounting evidence that such an approach is counter-productive in the long-term.

Do you really need to eat less calories to lose weight? Yes...but, you have to be careful that you do not restrict your calorie intake too much, otherwise you risk the prospect of halting your weight loss because you're not eating enough calories each day. I know that sounds so counter-intuitive, but the evidence supports the notion that you can eat too little and sabatouge your weight loss over the long-term.

This is something the "experts" repeatedly fail to tell you as they promote cookie-cutter calorie intake recommendations, most often 1400-1600 for women, and 1600-1800 for men trying to lose weight. These low calorie levels are often too low and provide too few essential nutrients! So in your effort to lose weight, you're actually giving your body a double-wammy - too few calories and too few essential nutrients!

Just to give you an idea of how counter-productive long-term calorie restriction can be, take a look at the data we have from a seven year study published last month in JAMA, that I wrote about in Seven Year Study of Low-Fat, High-Carbohydrate Diet. Over the seven year period of this study, participants reduced their calories (without being told to do so) from an average of 1788/day to just 1445/day. What happened? Nothing more than two-pounds of weight loss over the seven years! Their BMI at the start of the study was 29 and when the study ended their BMI remained at 29.

If that doesn't make you think twice about cutting calories, maybe another study from JAMA will help you understand how calorie restriction fails - Atkins, Ornish, Weight Watchers & Zone Study - that I penned earlier this week also highlights the failure of calorie restriction. The researchers didn't bother to note the dismal results of the calorie restriction and instead focused on the inability of participants to remain dedicated to their assigned diet.

And, let's not forget the data from the National Weight Control Registry! I've written about this particular study on a number of occassions, mostly to point out the very low calorie intake of those trying to maintain their weight - they average just 1400-calories each day and exercise intensely on top of that!

Is there a better way?

Yes!

The way to lose weight effectively and keep the weight off requires that you fulfill two metabolic requirements - you must meet your micronutrient requirements and you must not starve your body of the energy it absolutely must have to function each day without thinking you're living in a state of famine. If your body perceives "famine" it will do all it can to conserve energy to survive long-term - put simply, it will work hard to keep as much stored energy on your body as possible so it can continue to survive until the famine is over.

If you're overweight or obese, odds are high that you are consuming too many calories each day. To lose weight doesn't mean you must radically cut your calories to lose weight - what you really should strive for is a calorie intake that is appropriate for your normal body weight and then let your body slowly return to a normal weight with the calories it actually needs instead of the excess calories you're presently consuming.

Radical idea? Not really - if you put it into a perspective of where you want to be versus where you are right now. Let's say, for arguement sake, you weigh 250-pounds and are a woman who is 5'5" tall. If someone measured your calorie intake during the day, they may find you're consuming 2,800-calories each day. Shocking, isn't it?

Now, consider that a normal weight for your height is about 155-pounds - you want to lose the extra 95-pounds and are trying to figure out how many calories to eat. If you look to the "experts" you'll be restricted to 1400-1600-calories each day, but if you look to your normal weight calorie requirements instead, you'll eat 2,000-calories each day without risking "starvation mode." You could even start by eating 2,200-calories each day and still lose weight!

You simply do not have to starve yourself or your body to lose weight! And, if you take an approach that has a more balanced calorie intake - a calorie intake guided by your normal weight rather than a cookie-cutter, one-size-fits-all calorie recommendation, your odds are high for success and long-term maintenance!

5 comments:

  1. Calories do matter some. If you eat 10,000 calories a day, all of them coming from fat with a teeny bit of protein you will be in ketosis and have little insulin, but you WILL gain weight. I have to keep my calories under 2,000 a day if I want to just maintain my weight, never mind losing.

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  2. Hi Sly...thanks for the comments...to a certain degree I agree with you that while following a low-carb diet calories are less an issue than with other dietary approaches. The reason isn't that they don't count, or that you're not making insulin (protein stimulates insulin much like carbohydrate) - it's satiety.

    When you're eating adequate protein and a higher ratio of fat in your diet (one doesn't necessarily eat "more" fat in actual grams), you tend to reach a level of satiety more easily and for a longer period than when you consume higher amounts of carbohydrate which trigger satiety signals differently in the body (they take longer than protein to register you've eaten in the brain).

    This leads to a natural reduction in calories for most people following low-carb - study after study supports this notion that calorie intake is adjusted without being told to do so specifically...it's sponataneous.

    In the comparison study published in JAMA, I think this is highlighted to a degree (even though none of the groups were technically eating by the rules of their diets) in that the Atkins group ate more calories at every milestone of the trial and their weight loss was within the predictable range for calories in - calories out....unlike the other groups who significantly reduced calories more and did not see weight loss aligned with their calorie restriction!

    I think a lot of things come into play with weight loss - satiety just one item....nutrient-density another important factor. On a low-carb diet, from my analysis, you have better odds of meeting your nutrient requirements than when following a calorie restricted (on purpose) or low-fat diet.

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  3. My carbs have been around 40-50g a day, Brian. Fairly low. I can't do 100 a day without getting horrible cravings. Yesterday was 44g.

    I may not get that satiety effect like other people possibly due to my medication. I gained 40 pounds on a similar medication, and losing weight while on another weight gainer of the same drug class has been difficult. It's taken me nearly two years to lose 64 pounds. Additionally, these medications seem to cause carb cravings. A low carb diet helps control that, but is not 100% effective.

    Because I never feel totally satisfied with almost anything I eat, I have to count calories or I'd be eating around 2500 a day. Since my RMR is only 1610 (I have this tested at my gym), 2500 calories is way too many.

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  4. Anonymous8:52 PM

    Hi Regina;
    Wow it's hard to find information on this subject!~ After being a moderately chubby child I found myself suddenly 5ft7in and 128lbs after a rapid growth spurt. Coming from a chronically dieting family of 4 women I wanted to stay slim so over the next 10 years became a master at starving myself. I went from a size 7 to 15 with a 20lb weight gain. It was a rough time. Very low self body image that thankfully lead to regular exercise around 17 leading to a hobby of personal training as an adult. I embrace any information I can read on this subject as I am still a light eater by nature and although eat right and exercise regularly weight loss is a challenge unless I strick a perfect balance.
    Thanks for the article.

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  5. Anonymous8:44 PM

    Sorry, but the metabolism adjusts because weight has been lost. To continue losing weight at the same pace, you will continually need to drop calories in pace with the weight lost. However, once you get within the 15-20 pound range of weight left to be lost, it will no doubt come off much slower.

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