Lab Study: Purple Sweet Potatoes May Protect Against Colon Cancer
Purple sweet potatoes, like many deep red and purple foods, contain relatively high levels of a group of phytochemicals called anthocyanins that are well-studied for their cancer-preventive properties. A new lab study, published in Molecular Nutrition and Food Research, suggests that these sweet potatoes may play a role in protection from colorectal cancer.
The study conducted both a cell and animal study. The cell experiment compared the effects of anthocyanin extracts from the purple sweet potato to those found in berries and other red fruits on human colon cancer cells. The anthocyanins from the purple sweet potato extract inhibited the growth of colon cancer cells significantly more than the comparison extract.
In mice, study authors added the purple sweet potato to the diet of one group. Two other groups of mice consumed a cream-fleshed potato or a purple-skinned potato. A comparison group add their regular diet. After six weeks, researchers counted the aberrant crypt foci, early signs of changes in the colon that may lead to cancer. The mice eating the purple sweet potato-enriched diet had fewer large- and medium-sized formations of these abnormal formations compared to the other groups.
The scientists suggested that the proactive effects may be due to anthocyanins in the purple sweet potato being attached to other phytochemicals. This may provide anthocyanins with more stability that helps prevent them from breaking down by the body until they reach the colon – where they have their greatest effects. The purple sweet potatoes' unique mixture of anthocyanins may also have a synergistic effect, they note, but more research is needed.
Source: Soyoung Lim et al. "Role of anthocyanin-enriched purple-fleshed sweet potato p40 in colorectal cancer prevention." Molecular Nutrition & Food Research. Article first published online: 19 JUN 2013