Purple Potatoes Can Protect Your Colon from Cancer

Baked potato extract found to suppress the spread of colon cancer stem cells.

Purple potatoes have the potential to prevent the risk of cancer, scientists report. Baked purple-fleshed potatoes suppressed the growth of colon cancer tumors in petri dishes and in mice by targeting the cancer’s stem cells, a recent study found.

Attacking stem cells is an effective way to counter cancer, said Jairam K.P. Vanamala, associate professor of food sciences at Penn State and faculty member at the Penn State Hershey Center Institute.

“You might want to compare cancer stem cells to roots of the weeds,” Vanamala said. “You may cut the weed, but as long as the roots are still there, the weeds will keep growing back and, likewise, if the cancer stem cells are still present, the cancer can still grow and spread.”

Researchers chose the baked potato due to its status as a staple in the diet of most western countries. Since potatoes are typically cooked before they are consumed, scientists wanted to test whether or not their cancer-fighting properties were maintained after cooking.

The results of the study showed that the baked potato extract suppressed the spread of colon cancer stem cells while increasing cell death. Researchers then tested the effect of whole baked purple potatoes on mice and found similar results. The “dose” that scientists recommend to achieve this effect is one large purple-fleshed potato per day, or two medium-sized potatoes per day.

According to the researchers, there may be several substances in purple potatoes that work simultaneously on multiple pathways to help kill the colon cancer stem cells, including anthocyanins and chlorogenic acid, and resistant starch.

“Our earlier work and other research studies suggest that potatoes, including purple potatoes, contain resistant starch, which serves as a food for the gut bacteria, that the bacteria can covert to beneficial short-chain fatty acids such as butyric acid,” Vanamala said. “The butyric acid regulates immune function in the gut, suppresses chronic inflammation and may also help to cause cancer cells to self-destruct.”

In addition to starch, the pigmentation compounds that give potatoes their color may also be responsible for suppressing cancer growth.

“When you eat from the rainbow, instead of one compound, you have thousands of compounds, working on different pathways to suppress the growth of cancer stem cells,” said Vanamala. “Because cancer is such a complex disease, a silver bullet approach is just not possible for most cancers.”

The next step for scientists is to test the whole food approach using purple potatoes in humans for disease prevention and treatment strategies. Scientists also plan to test the effectiveness of potatoes in treating other types of cancer besides colon cancer.

The use of foods to prevent cancer could go a long way in complimenting current and future anti-cancer drug therapies. Since foods have limited side effects compared to drug treatments, they could actually serve patients with cancer better than traditional methods of combatting the disease.

“Instead, we have seen that the animals that consumed purple potatoes are healthier compared to animals that received drug treatment,” said Vanamala.