New research shows that a person's weight can also affect their ability to fight cancer.
Researchers at Albert Einstein College of Medicine compared the outcomes of breast cancer patients based on their weight.
They found those who were obese had a 30 percent increased risk for their disease coming back and a 50 percent higher risk of death.
Even women who were overweight, but not obese, had an increased risk.
They said hormonal changes associated with obesity may fuel certain cancers.