The Glycemic Edge: Keeping Off the Pounds

The Glycemic Edge: Keeping Off the PoundsBy Jose Antonio Ph.D.

There are some silly diets out there. Heck, some aren’t even diets per se; they’re ways of eating that are conducive to getting fat and jacking up serum triglycerides. If you don’t believe me, give the USDA Food Guide Pyramid a shot. Or whatever they call it these days; mypyramid. Either way, you can flip that frickin’ triangle any way you want and it’s still a moronic piece of dietary advice that has spread faster than a bad cold in a pre-K day care center.

So Antonio, what’s wrong with it? You mean, besides the obsession with processed carbohydrates (i.e., breads, grains, cereals, pasta, etc.)? I mean, who cares about the rest of it when the foundation of the pyramid is akin to building a skyscraper with chopsticks. If you really want to eat well, lose body fat, promote speedy recovery post-exercise, the key to all of this is not eating all those grains and cereals. The key is protein and low-glycemic-index carbohydrates.

According to sports nutritionist Abbie Smith, MS, CISSN, of the University of Oklahoma, “Protein is clearly the most important macronutrient for active individuals. It promotes recovery post-exercise and for those who are bodybuilding, consuming protein, especially the essential amino acids, has been shown to have a potent anabolic effect.”

The Glycemic Edge: Keeping Off the PoundsCertainly, carbohydrates are important. But you have to pick the right carbs. A bagel is not a good choice. Sweet potatoes are a good choice. Cereal is not a good choice. However, oatmeal (not the instant stuff) is a good choice. In fact, if you can stick to a high-protein diet, coupled with eating low-glycemic index foods— then, by golly, you’ll be on your way to a trimmer waist, a healthier heart, and more money in the bank.

OK, maybe not the last one, but you get my drift.

As they say on the hit TV show “CSI,” let’s follow the data. In the latest New England Journal of Medicine, scientists looked at various combinations of protein consumption, plus low- versus high-glycemic index carbohydrates. Overweight adults were given a (800-kcal) low-calorie diet; they were assigned to one of five diets over a 26-week or half-year period: a low-protein and low-glycemic-index diet, a low-protein and high-glycemic-index diet, a high-protein and low-glycemic-index diet, a high-protein and high-glycemic-index diet, or a control diet.

What did they discover? The average initial weight loss with the low-calorie diet was 24.2 pounds. In those who completed the study, only the low-protein/high-glycemic-index diet was associated with subsequent significant weight regain (3.7 pounds); that makes sense. One of the worst ways of eating is by following a high-GI-carb/lower-protein diet. Mmmm… sounds like the USDA Food Guide Pyramid.

The weight regain was 2.05 pounds less in the groups assigned to a high-protein diet than in those assigned to a low-protein diet, and 2.10 pounds less in the groups assigned to a low-glycemic-index diet than in those assigned to a high-glycemic-index diet. Also, the groups didn’t differ significantly with regard to side effects.1

The Glycemic Edge: Keeping Off the PoundsWhat’s the moral of this story? Two things: if you’re cutting calories, eat relatively more protein. Also, when choosing carbs, go for the low-GI types. Those include vegetables of all kinds, low-GI fruits, and pretty much most unprocessed carbs (except white potatoes). Another study confirmed this. Overweight women (18-65 years) were randomized to either a standard diet that was intended to be low in fat and relatively high in carbohydrates, or to a relatively high-protein (up to 30 percent of energy), relatively high-fiber (>35 grams per day; HPHF [High-Protein/High-Fiber]) diet for 10 weeks.

Those on the HPHF diet lost 2.86 pounds more bodyweight, 2.20 pounds more total fat and 1.54 pounds more truncal fat than those on the standard diet. And on the health front, total cholesterol and low-density lipoprotein (LDL) cholesterol were also significantly lower after the HPHF diet.2 Bottom line: eat more protein and fiber (which of course is found in low-GI carbs). Not only is it safe, it’ll slim you down.

Another study took 83 diabetic, overweight adults and gave them either a standard carbohydrate (CON; carbohydrate:protein:fat 53:19:26) or high-protein (HP; 43:33:22) diet, with or without supervised resistance training [RT] (three days/week) for 16 weeks. They discovered that the lower-calorie, HP diet combined with RT achieved greater weight loss and more favorable changes in body composition than exercise plus the standard (high-carb) diet.3 The secret? More protein and a lower glycemic load.

To top it off, what happens if you have achieved a stable bodyweight and decide to just jack up your protein intake? Scientists tested this out in which they gave protein supplements (protein group) versus a carb-fat supplement (same total kcals) to test subjects over a three-month trial period. Subjects were weight stable and did not change their physical activity. They found that subjects had greater fat-burning or oxidation as their protein intake went up.4 Eating protein is one of the keys to losing body fat and maintaining permanent weight loss. In fact, studies on teenagers show that a high-protein/low-carb diet is a safe and effective option for medically-supervised weight loss in severely obese adolescents.5 And get this, if you have a fat dog, a diet high in protein and fiber helps fat Fido remain trim and slim. Science proves it.6

According to noted sports nutritionist, Tim Ziegenfuss, Ph.D., “Whey protein is an excellent source of amino acids, the building blocks needed for lean body mass gain. Moreover, whey is great in that it blunts my appetite so that I don’t get food cravings; and the carbohydrate of choice should be the unprocessed low-glycemic-index variety.”

The secret to physique and performance success is what? Never skimp on protein, and reach for the low-glycemic-index carbohydrates.


1.                     Larsen TM, Dalskov SM, van Baak M et al. Diets with high- or low-protein content and glycemic index for weight-loss maintenance. N Engl J Med, 363: 2102-13, 2010.

2.                     Morenga LT, Williams S, Brown R, Mann J. Effect of a relatively high-protein, high-fiber diet on body composition and metabolic risk factors in overweight women. Eur J Clin Nutr, 64: 1323-31, 2010.

3.                     Wycherley TP, Noakes M, Clifton PM, Cleanthous X, Keogh JB, Brinkworth GD. A high-protein diet with resistance exercise training improves weight loss and body composition in overweight and obese patients with type 2 diabetes. Diabetes Care, 33: 969-76, 2010.

4.                     Soenen S, Plasqui G, Smeets AJ, Westerterp-Plantenga MS. Protein intake induced an increase in exercise stimulated fat oxidation during stable body weight. Physiol Behav, 101: 770-4, 2010.

5.                     Krebs NF, Gao D, Gralla J, Collins JS, Johnson SL. Efficacy and safety of a high protein, low carbohydrate diet for weight loss in severely obese adolescents. J Pediatr, 157: 252-8, 2010.

6.                     German AJ, Holden SL, Bissot T, Morris PJ, Biourge V. A high-protein high-fibre diet improves weight loss in obese dogs. Vet J, 183: 294-7, 2010.