 Why do people who eat legumes, beans, chickpeas, split peas, and lentils, live longer? Well, men and women who eat legumes tended towards being lighter, having a slimmer waist, lower blood sugars, lower cholesterol, lower triglycerides, better kidney function, lower blood pressure, so no surprise may live longer. But, interestingly, bean intake was a better protectant against mortality in women than men. They think this may be because cancer was the leading killer of women in this population, especially breast cancer. And we know that breast cancer survivors who eat soy foods, for example, have significantly lower likelihood of cancer recurrence. Eating soy foods appears to protect against the cancer coming back. This 2012 review looked at three perspective human studies done to date, and found that women who ate the most soy had a 29% lower risk of dying from breast cancer, and a 36% lower risk of cancer recurrence. And a fourth study was since published, and it showed the same thing. Soy food intake associated with longer survival and lower recurrence among breast cancer patients. With an average intake of soy phytonutrients above 17 mg a day, which is about what's found in a single cup of soy milk, the mortality of breast cancer may be able to be reduced by as much as 38%. Here's the survival curve over five years. The purple line represents the survival of the women with the highest soy consumption. As you can see, after two years, all the breast cancer survivors eating lots of soy were still alive. But a quarter to a third of the women who ate the least soy were dead. And after five years, 90% of the tofu lovers were still alive and kicking, whereas half of the tofu haters kicked the bucket. And you can see a similar relationship when you look at breast cancer survival and soy protein intake, as opposed to phytonutrient intake. How does soy so dramatically decrease cancer risk and improve survival? Soy may actually help turn back on BRCA genes. BRCA is a so-called caretaker gene, an oncosuppressor, meaning a cancer-suppressing gene responsible for DNA repair. Mutations in this gene can cause a rare form of hereditary breast cancer, popularized by Angelina Jolie's public decision to undergo a preventive double mastectomy. But only about 5% of breast cancers run in families. So 95% of breast cancer victims have fully functional BRCA genes. So if their DNA repair mechanisms are intact, how did breast cancer form grow and spread? Well, tumors do it by suppressing the expression of the gene through a process called methylation. The gene's fine, but cancer found a way to turn it off, or at least turn it down. Potentially facilitating the metastatic spread of the tumor. And that's where soy may come in. Maybe the reason soy intake is associated with increased survival and decreased cancer recurrences is because the phytonutrients in soy turn back on your BRCA protection, removing the methyl straightjack that the tumor tried to place on it. So researchers put it to the test. These are three different types of human breast cancer, specially stained, so that the expression of BRCA genes turns up brown. So this is what full DNA repair would look like, hopefully what normal breast cells would look like. Lots of brown, lots of BRCA expression, but instead we have column 2, Raging Breast Cancer. Well, if you add soy phytonutrients back to the cancer, BRCA does indeed get turned back on. The DNA repair appears to start ramping back up. Though this was at a pretty hefty dose, equivalent to about a cup of soybeans. The results suggest that treatment with soy phytonutrients might reverse DNA hypermethylation and restore the expression of the tumor suppressor genes, BRCA1 and BRCA2. May help with other breast cancer genes as well. Women at increased genetic risk of breast cancer may especially benefit from high soy intake.