We randomly assigned 811 overweight adults to one of four diets; the targeted percentages of energy derived from fat, protein, and carbohydrates in the four diets were 20, 15, and 65%; 20, 25, and 55%; 40, 15, and 45%; and 40, 25, and 35%. The diets consisted of similar foods and met guidelines for cardiovascular health. [emphasis added]
That emphasis hides a lot of sin, I'll bet. Well, no need to guess, as they provide a reference for such guidelines:
…consume a diet rich in vegetables and fruits; choose whole-grain, high-fiber foods; consume fish, especially oily fish, at least twice a week; limit intake of saturated fat to <7% of energy, trans fat to <1% of energy, and cholesterol to <300 mg/day by choosing lean meats and vegetable alternatives, fat-free (skim) or low-fat (1% fat) dairy products…
No wonder "high fat" is only 40%, and I'll bet they had a tough time getting even to that level. If I recall correctly, the average American diet is already about 30% from fat, so what are they showing? They certainly aren't emulating the Tokelauans at 50% saturated fat, or anything. Massai, Inuit? Forgetaboutit.
Well, I'm not going to spend a lot of time on this, because it's just ridiculous (with a shout out to: Frank M. Sacks, M.D., George A. Bray, M.D., Vincent J. Carey, Ph.D., Steven R. Smith, M.D., Donna H. Ryan, M.D., Stephen D. Anton, Ph.D., Katherine McManus, M.S., R.D., Catherine M. Champagne, Ph.D., Louise M. Bishop, M.S., R.D., Nancy Laranjo, B.A., Meryl S. Leboff, M.D., Jennifer C. Rood, Ph.D., Lilian de Jonge, Ph.D., Frank L. Greenway, M.D., Catherine M. Loria, Ph.D., Eva Obarzanek, Ph.D., and Donald A. Williamson, Ph.D. — hey, guys & gals; enjoy).
Simply A few points:
- There's no such thing as a "low fat diet." They're all high fat diets if fat loss is the goal.
- The lowest carbohydrate intake of all the diets was a whopping (yea, I can do the media hype, too) 35%. Presuming an average 2,500 kcal intake per day, that's about 220 grams of carbs — not "low carb" by any means. So, this is merely a comparison between various moderate to high carb approaches — approaches that leave insulin high and fat mobilization low.
- The highest fat intake is only 40%. A true high fat diet is 60%+ of energy from fat. You can't go above about 35% from protein, and that's pushing it (25% is more realistic). Simple: protein remains about the same, and the tradeoff is between carbs and fat. This study was heavily weighted in favor of carbs, particularly when one considers that carbs hammer insulin and fat has little to no effect. High insulin = no fat mobilization.
In conclusion, they proved that all diets with excess carbohydrate are crap and deliver virtually no results for most people. Hopefully, Dr. Eades will take this up. Stephan, at Whole Health Source, hadn't seen it until I emailed him. He laughed, of course, and might take it up.
I'll stay tuned.