Low fat diet disappointment
Low-fat diets failed to reduce the risk of breast and colon cancer and also fell short for cardiovascular disease, according to a large controlled intervention trial.
One group of women followed a low-fat diet, while another did not reduce the amount of fat they ate. The low-fat group showed slightly lower rates of breast cancer, colorectal cancer and heart disease -- but the differences were so small that they could be due to chance.
Researchers suggested that the women in the long-running study — with an average age of 62 — may have started their healthy eating too late. They also didn’t reduce fats as much as the diet demanded, and most remained overweight, a major risk factor for cancer and heart problems.
However, there were trends toward greater reductions in coronary heart disease risk in those with lower intakes of saturated fats or trans fats and higher intake of vegetables and fruits.
To Stanford University researcher Dr. Marcia Stefanick, chair of the Women's Health Initiative steering committee, "just adopting a low-fat diet is not enough. We really need to home in on getting nutritious foods into our diets.''
The researchers said they were not overly disheartened by the results. They said that the importance of different types of fat was not recognised when the investigation started, so the women were merely asked to reduce total fat consumption. In an editorial commenting on the study, Cheryl A.M. Anderson, Ph.D., M.D., and Lawrence J. Appel, M.D., M.P.H,. both of the Johns Hopkins School of Public Health, stressed that dietary policy has changed since the start of this study with more emphasis on types of fat.
With more data to come from this study in the future, the current research should allow those, who prefer the higher fat Mediterranean plan, where focus is put on the type of fat consumed, to rest more comfortably. The Mediterranean diet focuses specifically on the type of fat ingested. I think it's a winner.
(Dr. Dean Ornish responds to the study.)