Trends in carbohydrate, fat and protein intakes and association with energy intake in normal weight, overweight and obese individuals: 1971-2006.
American Journal of Clinical Nutrition 2011; 92:836-43.
This study looked at the changes in fat, protein and carbohydrate consumption in the
between the years of 1971 and 2006. The two population samples compared were the NHANES in 1971 and the NHANES in 2006. NHANES stands for National Health And Nutrition Examination Survey. It is a large study conducted every 2 years to examine the health and nutrition status of non-institutionalized U.S. civilian adults and children. Physical exams were performed in mobile units and diet was assessed by means of 24 hours dietary recalls. U.S.
The results were striking. Between 1971 and 2006 the prevalence of obesity in men increased from 11.9% to 33.4%. In women, obesity increased from 16.6% to 36.5%. During this time, carbohydrate consumption increased from 44% of calories to 48.7%. Fat consumption decreased from 36.6% to 33.7%. Protein consumption decreased from 16.5% to 15.7%. During this period the typical man consumed an additional 179 calories per day and women consumed an additional 199 calories per day.
Take Home Message: This study tells us 2 things: #1) As a country, we’ve bought into the whole low fat, high carb message over the past few decades. #2) It’s not working. As carbs go up and fat goes down, we are eating more calories and gaining more weight. Many government and health agencies are still promoting low fat, high carb diets as a weight management strategy. It’s time for a fundamental change in this philosophy.
Effects of omega-3 supplementation in combination with diet and exercise on weight loss and body composition.
American Journal of Clinical Nutrition 2011; 93:455-62.
The goal of this study was to determine if omega-3 supplementation can enhance weight loss when combined with diet and exercise. Subjects were randomized to two groups. 64 subjects received 15 grams of omega-3 supplements per day with an EPA:DHA ratio of 5 to 1. The other group of 64 received placebo pills. Both groups received diet advice as well as resistance training and cardiovascular exercise programs. After 6 months, the total amount of weight lost was compared. Both groups lost greater than 5% of their initial body weight. There was no difference in weight loss between the two groups.
Take Home Message: Despite preliminary research in animals suggesting that omega-3 supplements enhanced weight loss, it doesn’t look like it will do much in humans. Add omega 3 to the large and forever growing list of weight loss supplements that don’t really work.