A new study was released by the New England Journal of Medicine this week: “Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates”. In the study, 811 individuals were divided into 4 groups and each group adhered to a particular diet. The diets varied in macronutrient composition (meaning the percentagels of fats, proteins, and carbohydrates differed between the diets), but each one was intended to create a deficit of 750 calories per day. It’s probably not surprising that those who stuck with any of the 4 diets managed to lose weight:
At 6 months, participants assigned to each diet had lost an average of 6 kg, which represented 7% of their initial weight; they began to regain weight after 12 months. By 2 years, weight loss remained similar in those who were assigned to a diet with 15% protein and those assigned to a diet with 25% protein (3.0 and 3.6 kg, respectively); in those assigned to a diet with 20% fat and those assigned to a diet with 40% fat (3.3 kg for both groups); and in those assigned to a diet with 65% carbohydrates and those assigned to a diet with 35% carbohydrates (2.9 and 3.4 kg, respectively) (P>0.20 for all comparisons). Among the 80% of participants who completed the trial, the average weight loss was 4 kg; 14 to 15% of the participants had a reduction of at least 10% of their initial body weight.
So chalk one more up for moderation – the general conclusion here is that reducing calorie intake, not adhering to a particular diet, is the key.
In conclusion, diets that are successful in causing weight loss can emphasize a range of fat, protein, and carbohydrate compositions that have beneficial effects on risk factors for cardiovascular disease and diabetes. Such diets can also be tailored to individual patients on the basis of their personal and cultural preferences and may therefore have the best chance for long-term success.
On a more somber note, the New York Times reports that children are being negatively affected by their parents’ obsession with healthful eating. I think a lot about this subject as I try to provide my children with the most healthful choices available and affordable – I emphasize homemade meals (including sack lunches) made from whole, close to the source foods, mostly organic and locally grown. They do think of me as the food police, I fear, but I hope that what I am teaching them is not to fear food but to know what foods to choose more often – I don’t forbid those gummy worms (!?!) if they come our way, but I don’t often spend money on them myself, and I do expect that if lunch comes home unfinished, it does get eaten before the gummy worms disappear.
Some experts are quick to point out that it is not only parents who may contribute to children’s food anxieties. They cite nutritional programs in schools that may go overboard. “I see younger kids who have an eating disorder precipitated by a nutrition lesson in school,” said Dr. Leslie Sanders, medical director of the eating disorders program at Atlantic Health Overlook Hospital in Summit, N.J.
It really drives home the message that as adults we need to empower children to make the most beneficial nutritional choices – not by forbidding foods, not by labeling foods as “good” or “bad” (GrowingGreat actually does not allow the use of those words in their curricula), but by teaching them about food’s power to benefit the body and please the palate – and then letting them begin, at the later elementary school ages, to make their own decisions, in consultation with us at the beginning, and then on their own. I think as long as we approach the topic by teaching, rather than preaching, they will learn to choose what is most beneficial for their bodies and minds.