Low fat diet may help prevent breast CA

A low-fat diet probably does help reduce the risk of breast cancer, according to a lead researcher for the Women's Health Initiative (WHI) dietary modification trial.
In the study of approximately 49,000 women, breast cancer rates were 9% lower in those who were taught to eat a lower fat-diet than in the comparison group. The original hypothesis was based in part on findings of breast cancer rates that are up to five-fold higher in nations with high-fat diets, such as the United States, compared with those with low fat diets.
A report on the study in the February 8, 2006 JAMA said the low-fat diet did not result in a statistically significant reduction in breast cancer risk.
The researchers indicated that the benefit may not have reached a level of greater significance because dietary fat intake was not low enough in the dietary change group or that the follow-up period was not long enough.
WHI researcher Ross Prentice, PhD, said "We see a greater evidence of reduction in breast cancer risk among the group that started higher [in dietary fat] and made a bigger change. So these are data that you would not expect to see if the intervention was doing nothing relevant to breast cancer risk."
The risk of coronary heart disease was also assessed, and the low-fat diet did not significantly reduce the risk. However, the study did not target specific kinds of fat. "Saturated fat did not command the greatest attention in terms of the overall intervention," said Linda Van Horn, PhD, RD, who noted the first goal was to assess the impact of overall fat reduction on breast cancer. In addition, she noted there was no focus on trans fats because little was known about them at the time the research was conducted.