Scientific evidence has established that plant-based foods contain a rich supply of nutrients shown to reduce the risk for several types of cancer. Now, scientists from Harvard Medical School’s Beth Israel Deaconess Medical Center in Boston, have identified a compound called indole-3-carbinol (I3C) in broccoli, kale and other cruciferous vegetables that stimulates the production of PTEN, a protein that restricts tumor growth.

The next step for researchers is to use I3C to increase the potency of PTEN. “These findings pave the way toward a long-sought tumor suppressor reactivation approach to cancer treatment,” says Pier Paolo Pandolfi, MD, PhD, the director of the hospital’s cancer center.

William Li, MD, president and medical director of The Angiogenesis Foundation and the author of Eat to Beat Disease: The New Science of How Your Body Can Heal Itself, has for years stressed the key role that food—combined with drug therapies—can play in cancer treatment and prevention.

But the team isn’t suggesting that eating lots of cruciferous vegetables could have the same effect. “For a start, a person would have to eat around six pounds of raw sprouts per day to reach an effective level of I3C,” Pandolfi says.