Fat Facts
I was very pleased to see that Dean Ornish is now writing a column for Newsweek magazine, and that Andrew Weil will be contributing to Time. This is good news: both of them have made original contributions to holistic health care, and have always been very reasonable in their pronouncements.
Dean’s debut column has just come out. As you might expect, given his long history of making valuables contributions to the diet debate, he has called his article The Facts About Fat, and he reports on an important article published earlier this month in The Journal of the American Medical Association. The study presents some of the results of the Women’s Health Initiative dietary modification study, which followed nearly 49,000 middle-aged women for more than eight years. The study compared those on a regular diet to those on a low-fat diet, to see if dietary modification could help prevent heart disease and cancer. The women in the “dietary change” group were asked to eat less fat and more fruits, vegetables, and whole grains each day to see if it. The women in the comparison group were asked to continue on their usual diets.
The results of the study have caused some consternation, because low-fat diets did not appear to protect against heart disease, or stroke, or breast cancer, or colon cancer. But here we come back to a point that I have made in other articles. We must not take studies at face value, but instead analyze the data in detail. It is hard work to extract the real message from published data, but it is incredibly important to do so.
So what were the limitations of this study?
1. The reduction in dietary fat was very small.
2. People are not good at keeping diet diaries, and often think that they are eating more healthily than they are. (Some years ago we did an experiment in which we estimated our daily calorie intake and also kept diet diaries. We were all experts in human nutrition, but each of us under-estimated out intake by about 300-500 calories per day)
3. The increase in consumption of fruit and vegetables was small.
4. The control group that was supposed to stay on their regular diet actually did not. Most of us know something about healthy eating, and most people are making some changes toward better diets.
5. Eight years is actually quite a short duration for a cancer prevention study.
Dean then returns to a favorite and important theme: the study didn’t distinguish between beneficial and harmful fats. Several previous studies have shown that the omega-3 fatty acids found in salmon, halibut, mackerel, walnuts, and flax seed oil may reduce your risk of a heart attack by 50 percent or more, as well as perhaps reducing the risk of inflammation and some forms of cancer.
I am certainly persuaded by the data on omega-3 fatty acids, as well as recent evidence indicating that reducing overall dietary fat to around 33 grams of fat per day, reduces the risk of breast cancer recurrence by 42%.
Dean also endorses another comment that I have made in previous posts: what you include in your diet is as important as what you leave out.
Technorati tags: Dean Ornish, Newsweek, Nutrition, low-fat diet
Dr. Richard G. Petty, MD is a world-renowned authority on the brain, and his revolutionary work on human energy systems has been acclaimed around the globe.
He is also an accredited specialist in internal and metabolic medicine, endocrinology, psychiatry, acupuncture and homeopathy. He has been an innovator and leader of the human potential movement for over thirty years and is also an active researcher, teacher, writer, professional speaker and broadcaster. He is the author of five books, including the groundbreaking and best selling CD series Healing, Meaning and Purpose. He has taught in over 45 countries and 48 states in the last ten years, but spends as much time as possible on his horse farm in Georgia.
