Tuesday, April 17, 2007

What's so Special about Protein Anyway?

When we hear the word "diet" we often conjure up thoughts of deprivation, hunger and the frustration of short-term attempts to lose weight. But "diet" also means how we eat on a daily basis - so the diet we eat to lose weight should, ideally, be the diet we eat for the long-term.

I agree with this idea and strongly encourage those trying to lose weight to eat a dietary pattern they'll make habit over the course of their weight loss and beyond as they then maintain their weight.

Where I disagree with this idea is in the idea that our macronutrient (protein, carbohydrate, fat) intake should be set by percentage of our calories, in strict ratios with each other, in an attempt to keep the equation "balanced" - up to 35% of calories from total fat, less than 10% (or less than 7%) of calories from saturated fat, 55-65% of calories from carbohydrate, and the remaining 10-15% of calories from protein.

We're repeatedly told a "balanced diet" remains within these percentages of calories and to maintain them while in a calorie deficit if we're trying to lose weight; going beyond those percentages and consuming too much fat, saturated fat or protein is detrimental to our long-term health.

Yesterday I closed my post with "The first, and most important rule you need to know in the "diet game" is eat your protein; and make it complete protein."

Protein is the macronutrient we take for granted, underestimate the power of, and assume we get enough of each day in our diet.

By undervaluing protein in our diet, by making the assumption that most people eat more than enough, we fail to focus on not only the building blocks of life itself, but the building blocks of our endocrine system - our hormone system.

Without adequate intake of essential amino acids, we rob our metabolism of the building blocks to function normally.

When we diet to lose weight, restrict calories and maintain the ratios suggested to keep our diet "balanced," we willfully starve our metabolism and endocrine system of the critical elements required to maintain function.

This is because our requirement for protein, for essential amino acids, is not based on a simple percentage of calories, but on how much we weigh.

If a woman, who is 5'6" tall, 30-years old and weighs 250-pounds goes to MyPyramid.gov, she'll be presented with a food plan providing 1,800-calories a day to gradually lose weight.

She will find her recommendation includes:
6-ounces of grains (Aim for 3 whole grains)
2.5-cups of vegetables
1.5-cups of fruit
3-cups of milk
5-ounces of meat and beans
Aim for 5-teaspoons of oils a day
Limit extras (extra fats & sugars) to 195-calories a day

The first critical problem with the recommendation is the calorie level - our hypothetical woman above has a Basal Metabolic Rate calculated at 1900-calories a day.

As the Discovery Health BMR Calculator page says "You expend energy no matter what you're doing, even when sleeping. Thus your Basal Metabolic Rate is the number of calories you'd burn if you stayed in bed all day...depriving yourself of food in hopes of losing weight also decreases your BMR, a foil to your intentions."

But let's set that aside for this post and look at what she is presented with as a food plan and determine if it meets her nutrient requirements, as the site contends it will.

First let's pretend she laughs off the idea of eating beans instead of meat - this makes our task of examining her protein intake easier since we'll be able to determine her intake of complete protein without having to adjust for the limiting amino acids in grains or legumes (beans).

With 3-cups of milk and 5-ounces of meat, the total intake of complete protein (if this is followed to the letter) is 56-grams.

Now, some would contend that this is above the 46g DRI (Dietary Reference Intake) established by the Institutes of Medicine for a 30-year old female. Such a contention fails to consider the IOM basis of 46g of complete protein is based on a female who weighs 128-pounds. Our hypothetical woman weighs 250-pounds!

Protein intake - that is complete protein, providing all essential amino acids in the proper ratio - is based on the formula 0.8g/kg body weight. The IOM considers this the absolute minimum required each day. So, our hypothetical woman, who weighs 250-pounds is 113.6kg, thus requires a minimum of 91g of complete protein each day.

But wait, you might say, she has other things she'll eat that provides protein!

That is true. But, with 1800-calories, planned as recommended above, she'll consume about 80-90g of total protein, and depending upon what she actually eats, she is likely to miss adequate intake of all her essential amino acids; even with careful planning and optimal selections of whole foods, she'll also likely fail to meet DRI for Potassium, Vitamin D, Niacin, Magnesium, and Vitamin E; add to this she'll likely fail to meet omega-3 requirements while consuming an excess of omega-6.

But hey, her saturated fat intake is just 6% of her calories, her cholesterol intake would be about 100mg, and her fiber intake in the neighborhood of 35g - according to the recommendations, she's eating a "healthy diet," and reducing her risk of disease by keeping her saturated fat and cholesterol intake below the maximum allowed.

On paper her diet looks just great!

In her body, in her metabolism, it's a nightmare if followed for any length of time.

This is because chronic, habitual nutrient deficiency - whether it is a diet deficient in vitamins, minerals, or trace elements, essential amino acids, essential fatty acids, or a combination of deficiencies - places a burden on the metabolism to function without all of its needs.

Oh, you won't die with a shortfall in nutrients; atleast not immediately...no, your metabolism will continue limping along, as best it can with what you give it to work with.

But really, do you want to do that, or do you want to eat in a way that optimizes your metabolism?

How about we design a menu for our hypothetical women, one for her, that is designed specifically to meet her nutrient requirements rather than conform to a set of percentages.

Based on what we know her Basal Metabolic Rate is (what she needs for basic function before she gets moving each day), she should consume 1,900-2,000 calories and first focus on ensuring she eats 91g of complete protein each day.

If we start there, and include as part of her day 4-ounces of lean roast beef, 16-ounces of plain whole milk yogurt, 3-ounces of tuna in oil, 2 eggs, and 1/4 cup shredded natural cheddar cheese - we've included all her complete protein for the day - 91g - and started her menu with 946-calories. We have 954-1054 more calories to add to her menu.

Now we get to add in her vegetables, fruits and other foods to ensure she consumes adequate intake of the additional nutrients needed; the focus here should be first on vegetables since they're rich with vitamins, minerals and trace elements.

Let's add to her menu a salad for lunch, with 2-cups of romaine, 6 cherry tomatoes, 1/2 a sliced cucumber, 1/2 cup shredded red cabbage, and some crimini mushrooms and we'll let her top it with olive oil and vinegar; then she'll have 1-cup of steamed broccoli at dinner with her roast beef and she can indulge and include 1-tablespoon of butter to make it taste good.

As part of her breakfast, which includes the two eggs above, she'll also include 1-cup of baby spinach (raw amount to be added to egg omelet) and 1/4 cup of shredded cheddar cheese. Her breakfast will also include the one of the two cups of plain yogurt, in which she'll add 1-cup of strawberries.

Her snacks during the day will include 1-ounce of almonds with 1-ounce of sesame seeds; she'll include 1-cup of blueberries with the other 1-cup of plain yogurt, add some water and have a delicious smoothie; and she'll have 1/2 an avocado too, perhaps with her lunch or just a snack during the day.

At this point, her menu provides 1,931-calories.

But wait, she hasn't included any grains! Surely this menu is going to be deficient for essential nutrients if she isn't eating grains!

Not so fast.

The above menu provides all essential nutrients, including fiber, with one notable exception - vitamin D, the most difficult nutrient to obtain from food. She can, of course, go out in the sun for 20-minutes this time of the year each day and make all the vitamin D she needs in her skin. In months where we cannot produce vitamin D in our skin, she can add a vitamin D supplement or make different choices with foods rich with vitamin D or include cod liver oil.

But the above menu, even though it provides all essential nutrients, is a nightmare for those espousing the dietary recommendations - it's high in total fat, saturated fat and exceeds maximum allowance for cholesterol; the carbohydrate is lower than recommended (even though fiber is above recommendations), and it does not include any grains!

Which begs the question - what would you rather eat?

A menu designed to meet your calorie requirements to function before any activity but still a calorie deficit to enable weight loss - designed to provide all essential nutrients including the critical essential amino acids and essential fatty acids - or - a menu that looks pretty on paper but fails your endocrine system because it is nutritionally bankrupt?


  1. I've said a number of times that diets based on percentages of calories are not great. A much better way is based on weight as you did here. But, I would argue that you protein, and calories, are too low. In addition, get this person up off the couch and into some exercise. Preferably some High Intensity Strength training!! :-)

  2. Anonymous10:59 PM

    Since, for the vast majority of people, protein needs are roughly proportional to calorie intake, and there is a range of safe protein intake, I see little wrong with using % of calories as the basis of specifying macronutrient ratios.

    Also, I wouldn't recommend _any_ diet for the person described without first examining their blood chemistry to check for insulin resistance or high insulin levels. This could have a major impact on recommended carb intake, and accompanying weight loss. The emphasis on calorie control, protein intake, and exercise in the above posts may largely be a waste of time if the major problem is due to insulin levels depressing fat oxidation rates in this person.