Is there a magic formula for weight loss – certain foods that will melt off the fat or combinations of nutrients that work wonders? One would think so, based on the number of books and internet sites that promise to offer the answer, the only answer.
After reading many of the claims and current research that examines different strategies, I am convinced of two things:
1. There is no single way of eating – no magic food and no magic combination – that will work best for everyone. We all have unique genetic backgrounds that affect health and appearance, and arguably more important, we have different personalities and food preferences.
2. Calories are the most important determinant of body fat stores. Excess calories from any source will end up somewhere on the body in the form of fat.
A recent study published in the Journal of the American Medical Association showed that calories determined the amount of fat gained during 8 weeks of overfeeding of healthy people in a controlled clinical setting. Three groups of men and women were fed varying amounts of protein: low (5%), moderate (15%), and high (25%).
Although the lowest protein group gained less weight than the other two groups, they had none of the muscle growth or increased metabolism that the other two groups experienced. Weight gain, lean mass gain, and metabolism increase were similar for the two higher protein groups.
A couple of points deserve mention. First of all, the low protein group was well below what almost anyone in the U.S. normally eats. The study found that 77 grams of protein was the amount needed to prevent loss of lean mass in the study participants.
Another important consideration is that this was an overfeeding study, so the muscle mass gained by the two higher protein groups was accompanied by a gain in fat mass, not what most people are hoping to achieve. In other words, overfeeding of protein will not prevent expected fat gains explained by excess calories.
The bottom line: This study showed that excess calories determine fat storage, not the blend of carbohydrates, fats, and protein. The amount of protein affected the amount of lean mass and metabolism, but above a threshold of about 77 grams per day for the study participants, there was no additional benefit seen.
A successful weight loss plan will need to include enough protein to minimize the loss of lean mass, while decreasing calories below the number burned. Most importantly, the plan will only be as successful as the degree of adherence to the plan!