Besides skin cancer, breast cancer is the most common cancer among American women. To demonstrate how dramatically lifestyle choices may impact breast cancer risk, researchers followed about 30,000 postmenopausal women with no history of breast cancer for about seven years. Limiting alcohol, eating mostly plant foods, and maintaining a normal body weight was associated with a 62 percent lower risk of breast cancer.
Remarkably, eating a plant-based diet along with walking every day may improve our cancer defenses within just two weeks. Researchers attributed this effect to a decrease in levels of a cancer-promoting growth hormone called IGF-1, likely due to the reduced intake of animal (meat, egg white, and dairy) protein.
What about carcinogens in cooked meat? Women who eat more grilled, barbecued, or smoked meats over their lifetimes may have as much as 47 percent higher odds of breast cancer.
Consumption of animal-based products have also been implicated in earlier onset of puberty for girls, which had begun when girls were on average 16 or 17 until the 20th century, but now we see significant numbers of girls starting to grow breasts before they’re 8 years old, and increased risk of infertility.
Polycystic ovary syndrome (PCOS), potentially the most common hormonal abnormality among young women in the United States and a common cause of infertility, menstrual dysfunction, and excess facial and body hair—may also be affected by diet. Advanced glycation end products (AGEs) may contribute to the cause of PCOS and infertility. So, in addition to not smoking, we should decrease consumption of foods high in protein and fat, and rich in AGEs, such as meat, cheese, and egg yolks, and increase intake of foods high in antioxidants, such as berries, herbs, and spices.
Plant-based diets appear to offer relief from a variety of menstrual symptoms, including bloating and breast pain (cyclical mastalgia), and women suffering with dysmenorrhea—painful, crampy periods—who switch to a plant-based diet experience significant relief in menstrual pain intensity and duration.