For the first time, a large experiment suggests that trimming dietary fat and eating more fruits and vegetables may lower a woman’s risk of dying from breast cancer. The findings of this large, long-term study could have life changing results for millions of women.

In a new study being presented at the annual American Society of Clinical Oncology meeting in Chicago last month, researchers report intriguing evidence that a low-fat diet, similar to the kind of which doctors recommend for heart health, is also linked to a lower risk of dying from breast cancer.

As part of the study, about 20,000 women were coached to change their diets in a number of ways for at least eight years. “We asked women to reduce their total fat intake,” explains Rowan Chlebowski of the Los Angeles Biomedical Research Institute at Harbour-UCLA Medical Center. In addition, the women were asked to eat more fruits,vegetables and grains. A comparison group of nearly 30,000 women contributed to follow their normal diet.

The strength of this study is twofold: it’s size, nearly 50,000 women in all, and it’s long-term follow-up, nearly 20 years. During the study, some women in both groups were diagnosed with breast cancer, but those who had changed their diets had a 21 percent lower risk of dying from the disease.

Chlebowski noted that these findings were particularly interesting given that the intervention group did not hit its target goal of reducing fat intake to 20% of total energy, but still managed to see significant benefits while only reducing their intake to 24.5%

During the presscast, Chlebowski also mentioned a separate study that will be presented at ASCO, investigating the same dietary modification in women with poor metabolic factors such as diabetes and blood pressure.

In conclusion, Chlebowski explained, this research shows that dietary changes can significantly influence a women’s risk of dying from breast cancer. “Ours is the first randomized, controlled trial to prove that a healthy diet can reduce the risk of death from breast cancer. The balanced diet we designed is one of moderation, and after nearly 20 years of follow-up, the health benefits are still accruing,” he said.