Increase your metabolism and burn more calories by eating whole food meals rather than processed foods. You probably know processed foods are less nutritious and often contain more additives. New evidence indicates that you’ll support a better body composition by avoiding processed foods in your diet.
A study from Pomona College in California compared the thermic effect of eating a processed cheese sandwich meal (processed cheese product and white bread) with a whole food cheese sandwich (bread with whole grain kernels and sunflower seeds and cheddar cheese). Both meals contained the same number of calories and a similar proportion of carbohydrate, protein, and fats.
The diet-induced thermic effect of food is the amount of calories required to break down food, synthesize enzymes, and perform metabolic processes. It is typically about 10 percent of daily energy expenditure. Protein burns the most calories, followed by carbohydrates and then fats.
The thermic effect of the whole food meal was almost double that of the processed food meal. That’s right—participants burned 50 percent more calories after eating whole foods!
Equally significant is the fact that the participants who ate the processed food meal had their metabolic rates drop below their average basal metabolic rate (BMR)—the average energy needed to keep the body functioning at rest—during the sixth hour after eating. The whole food meal group never fell below the BMR.
The reason for the dramatic difference in calorie burn for the two meal types is due to variation in the quality of the ingredients and fiber content between the two meals. The processed food meal contained refined grains without bran or germ and only about one-third of the fiber of the whole food meal. The refined quality of the processed food ingredients means it is more easily digested, ultimately burning fewer calories in the process.
Researchers note that the ingredients used for the whole food meal did require some food refinement and processing to produce, but not nearly as much as for the processed food ingredients. They suggest that eating a stricter whole foods diet of fruit, vegetables, and meat devoid of processing would likely increase the thermic effect even more. Eating a diet of “whole foods” can also help shift the diet to include more protein and toward a better make up of carbohydrates.