Cutting calories could cut risk of disease
cholesterol levels who followed a low-fat and low-calorie diet not
only lost weight, but also significantly enhanced their immune
response.
Agricultural Research Service scientists have found that people with high cholesterol levels who followed a low-fat and low-calorie diet not only lost weight, but also significantly enhanced their immune response.
If the results of the small study are confirmed in a larger trial, they could give further impetus to the belief that good food is connected to wellbeing. Losing weight would however also offer an alternative solution to taking immune-enhancing supplements.
The 10 volunteers in the ARS study consumed different diets during four distinct test phases lasting more than one month each. The first three phases were designed to maintain body weight, and the last phase was not. The researchers tested the volunteers' immune functions through blood tests and skin-patch tests geared to measure immune response at the end of each phase.
As a baseline for comparison, the 10 volunteers were provided an average American diet with 35 per cent of calories as fat (16 per cent as protein and 49 per cent as carbohydrate). The researchers then gave the volunteers three additional diets: one with 26 per cent fat (reduced fat); one with 15 per cent fat (low fat); and the last with 15 per cent fat, but also with reduced caloric intake.
Cholesterol levels were significantly reduced during all phases,compared to the baseline-diet phase, reported the team in a recent issue of the Journal of the American College of Nutrition. But during skin-patch tests after the last phase, the volunteers showed significantly better immune responses than after any of the other three phases of the study. Blood tests also indicated enhanced cellular immune response, they reported.
Experts estimate about 102 million Americans with high cholesterol are at increased risk of heart and other disease. These findings also suggest that decreasing cholesterol levels would reduce risk of many other symptoms.
The authors concluded that high-cholesterol individuals who follow recommended low-fat diets are unlikely to erode their immune systems, and they may well improve their immune response if they lose weight at the same time.
The researchers are planning more studies to gauge the effects of caloric restriction on health status and immuneresponse in larger groups of volunteers.
