Study finds that a focus on eating the “right” foods beats traditional calorie-restriction
by Craig Weatherby
The results of a diet-vs.-diet study bear good news for disciples of low-carb, lean-protein, but nutrition-savvy diets like the antiinflammatory-foods approach first described and championed by Nicholas Perricone, M.D.
The findings gained wide coverage when reported last week at the 2005 conference of the North American Association for the Study of Obesity, after being quietly unveiled at the annual Experimental Biology conference in April of 2005.
In short, the results support the contention that an “eat-the-right-foods” focus works better than a traditional calorie-conscious approach to weight loss, at least for the critical first three months.
Smart, satisfying foods versus traditional calorie-counting
The study involved 87 overweight-to-obese men and women aged 18 to 65, who followed two different diets for nine months.
Half the participants were randomly assigned to follow a traditional low-fat, portion-controlled diet, in which they were told to consume 500 to 800 calories a day less than normal.
The other half followed a “modified-carbohydrate diet" (MCD) consistent with the weight control recommendations outlined in The Perricone Weight-Loss Diet.
The people in the MCD group were told to emphasize lean protein foods—a category which included fish—as a prime source of calories. They were also told to reduce carbohydrate intake overall, and to favor nutrient- and fiber-rich whole grains over starchy, low-fiber carbohydrates such as pasta, breads, pastries, chips, and potatoes.
During the first 12 weeks, each of the two divergent diets prescribed a relatively rigorous regimen focused on weight loss. For the remaining six months, the participants were instructed to follow more relaxed versions of each diet, intended to maintain any weight loss achieved in the first phase.
Perricone-style diet wins out, and bears big side benefits
Compared with the people on the low-fat, portion-controlled diet, the volunteers on the modified-carbohydrate diet (MCD) lost significantly more weight and body fat during the first 12 weeks. After the full nine month period, both groups had lost weight, but the MCD group lost weight more quickly than the control group.
Because motivation is critical to attempts to maintain dietary discipline, the faster, greater weight loss the MCD group enjoyed during the first 12 weeks is a critical advantage. When people see results sooner, they are more likely to stick with a dietary program, whatever it may be.
In addition to greater, faster weight loss in the first 3 months, the participants who followed the MCD diet enjoyed three important side benefits:
- Significant improvements in fasting triglyceride (blood fat) levels.
- Significant improvements in the ratio of HDL (“good”) cholesterol to total cholesterol.
- Greater reduction in glycemic load (blood sugar levels) after the first 12 weeks. (Chronically elevated blood sugar is a risk factor for diabetes.)
Dr. Perricone's approach bears a superficial resemblance to the Atkins diet, in that it favors protein and fat over carbohydrates as the dominant source of calories. But the resemblance ends there. Unlike Atkins, who made no distinction among protein sources—e.g., fatty steak was fine with him—Dr. Perricone recommends lean protein, especially wild salmon and other omega-3-rich fish. Unlike Atkins, he also emphasizes the importance of the satiating, anti-inflammatory effects of antioxidant-rich plant foods—colorful vegetables and fruits, as well as nuts, whole grains, and beans.
Note: While wild salmon, sardines, tuna, and sablefish do not fit into a traditional definition of “lean” protein, these omega-3-rich fish are recommended by Dr. Perricone, Dr. Weil, and the creator of the imitative South Beach Diet. This is because the metabolic effects of the omega-3s that constitute the majority of their fat discourage weight gain, thereby making fatty fish functionally lean.
We commend Dr. Perricone for pioneering a highly nutritious approach to eating that appears to help many people reduce or control their weight, and reduce the rate of internal and external aging, without feeling deprived: an approach so successful that it's inspired some high-profile imitators.
- Maki KC, Rains TM, Kaden VN, Quinn J, Davidson MH. A randomized, controlled clinical trial to evaluate the efficacy of a modified carbohydrate diet for reducing body weight and fat in overweight and obese men and women. Session#: 448, Program/Abstract # 448.5, April 3, 2005. Experimental Biology 2005. Accessed online October 21, 2005 at http://www.eb2005-online.com/pdfs/004956.PDF?PHPSESSID=1c3b0454d98b47ca5a0cbd6c57920e37
- Maki KC, et al (same study as above). Abstract # 308P at the conference of the North American Association for the Study of Obesity, Vancouver, BC, October 15-18 2005.