Obesity is associated with both a shorter recurrence time and a higher mortality rate (death rate) in those with breast cancer (both premenopausal and postmenopausal women). The American Cancer Society's Prevention Study II has shown that obese women with breast cancer have a mortality risk more than two times greater than women with breast cancer with a healthy BMI. Keeping a healthy weight is inarguably extremely important for those with breast cancer, and the best way to do that is through a healthy diet and exercise. 

Furthermore, two new studies have shown that, along with maintaining a healthy weight, what you eat is also has an impact on breast cancer outcomes.

• The first study showed that women with a higher intake of fruits and vegetables (especially cruciferous vegetables such as broccoli, cauliflower, and brussel sprouts), have a lower risk of dying from breast cancer. Those who ate one serving of cruciferous vegetables per day had a 13% lower risk, and those who ate two servings or more per day had a 20% lower risk of dying. 

• The second study showed a link between the type of carbohydrates that women eat and breast cancer outcomes. The study showed that women who ate high-glycemic carbohydrates (processed foods, fast food, and sugary beverages), had a higher mortality rate than women who ate whole grain and high fiber carbohydrates (such as whole grain breads/pasta, brown rice, farro, quinoa, etc.). 

All in all, studies have shown that those with breast cancer should try to eat a diet full of fruits, vegetables, and whole grains.