
A 2-year Federal Study Finds that Calorie Reduction, Not Proportions of Fat, Carbs, or Protein, Lead to Weight LossA new federal study found that reduced calories are key to weight loss regardless of amount of proteins, carbohydrates or fat. The study examined 811 participants, 38% of them men, 62 % women, all overweight or obese, between the ages of 30 and 70 years of age. Each subject was put on a reduced-calorie diet for two years with different proportions of proteins, carbs, and fats.
“The diets all used the same calorie reduction goals and were heart healthy, low in saturated fat, and cholesterol while high in dietary fiber,” said researchers whose findings will be published Thursday in the New England Journal of Medicine. Carbohydrates with a low glycemic index were recommended in each diet.
Participants also participated in group and behavioral counseling during the two-year study. Participants were asked to keep a food journal and participate in 90 minutes of moderate exercise per week, monitored through questionnaires.
The participants lost an average of 13 lbs. over a 6-month period while sustaining a 9 lb. loss (gained 4 lbs.) for two years. The study’s findings help to reiterate that as long as a person chooses healthy and nutritious foods, a reduced calorie diet, no matter which approach, can result in weight loss and healthy weight maintenance.
Dr. Elizabeth Nabel, director at the National Heart, Lung, and Blood Institute, said “This provides people who need to lose weight with the flexibility to choose an approach that they’re most likely to sustain: one that is most suited to their personal preferences and needs.”
This study helped provide answers to a subject of very intense debate over the last years. With the 100s of diets out there, the question everyone asks is, “Do diets work?” “The answer, in most cases, is yes!” states Kristen Harvey, Chattanooga personal trainer and fitness expert. “But not every diet will work for you.” Mrs. Harvey adds. “While Miss Suzie Homemaker might enjoy a flavorful, gourmet diet like the Sonoma Diet, Joe Schmo , a single guy who spends most of his nights at Taco Bell, might fall in love with the new “Burrito Diet.”
Mrs. Harvey offers additional take-home lessons reported in the NHLBI study. First, participants with the highest attendance at the group sessions had the highest rates of success with their weight loss goals. Whether or not this was attributed to the person’s level of commitment or the effectiveness of the group sessions is hard to say. But the support and accountability that came from attending the group sessions and individual consults was important to a person’s success.
Second, participants were asked to choose low-glycemic foods. While the amounts of fat, protein, and carbohydrates varied, the diets were all low in sugar. The proportion of fats, proteins, or carbohydrates did not make a difference on weight loss. However, sugar may significantly sabotage a person’s weight loss results.
Finally, although the weight loss was statistically significant, a 9-lb. weight loss in 2 years is an EXTREMELY inefficient weight loss program. While it is important to eat a healthy diet and exercise in order to lose weight, 90 minutes of moderate physical activity per week is not adequate to achieve significant health benefits.