A new study shows that a low-fat diet can reduce up to 56 percent the risk of early death in patients with early stage breast cancer, especially the ER-negative or ER-negative and PR-negative one. The findings were presented Friday at a breast cancer meeting in San Antonio.
The study involved over 2,400 female participants diagnosed with early breast cancer between 1994 and 2001. Almost 1,600 of them had ER-positive breast cancer, while the rest had ER-negative +/– PR negative type of cancer.
Beside adequate treatment, half of the women also received nutritional counseling and the assignment to cut down on their daily fat intake by 10 percent in the next five years following the treatment. Every year, researchers randomly called these women and asked them to report what their fat intake was during the past 24 hours. The study was conducted over a 15-year period.
“It was the first study of its kind that got women over a long period of time to follow a low-fat diet to influence outcomes in breast cancer patients,”
Dr. David Heber, founder of the UCLA Center for Human Nutrition, said.
During the five-year trial period, these women reduced their daily fat intake from about 29 percent to 20 percent and also lost on average six pounds.
By the end of the study, the low-far diet led to a 36 percent reduced risk of premature death in women with ER-negative breast cancer than in women with early breast cancer that hadn’t followed a low-fat diet. But, women with both ER-negative and PR-negative cancer had an even lower premature death risk by staying on a low-fat diet. Their overall risk of dying was reduced to 56 percent.
Dr Rowan Chlebowsky, lead author of the study and oncology researcher at the UCLA Medical Center, also analyzed the death rate in both study groups – the low-fat diet and the regular group. He found that women on low-fat diet, regardless of their type of cancer, had a 3 percent lower death rate than women on a regular diet. However, the findings were statistically insignificant.
Statistically significant were the figures found by Dr Chlebowsky when analyzing the subgroup of ER-negative +/– PR-negative.
Though, researchers could find neither a direct cause-effect link between a low-fat diet and lowered risk of breast cancer death nor a valid explanation to why ER-negative cancer patients seemed to benefit more from this diet.
Dr Chlebowski believes that the diet led to weigh loss that triggered a reduced inflammation in those women’s bodies. A high level of inflammation is known to favor cancer growth.