Strawberries are a summertime favorite, prized for their sweet flavor. But research shows these berries may be delivering even more than meets the eye. It’s worth noting that berries have been studied extensively for their potential cancer-fighting capabilities.
Swedish researchers have found that extract from organic strawberries are particularly effective at stopping the growth of cancer cells. The organic strawberries were found to contain more antioxidants and a higher ratio of ascorbate compared to its oxidized form, dehydroascorbate.
Strawberries are rich in cancer-fighting qualities
The Swedish researchers concluded that extracts from organically grown strawberries halted cancer cell proliferation more effectively than extracts from conventionally grown ones, and in both types of cancer cells. They found the difference between organically produced strawberries and conventional ones to be statistically significant.
Two of the primary cancer-fighting components of berries are vitamin C and fiber, and berries are good sources of vitamin C and fiber. The American Institute for Cancer Research’s report, “Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective,” found that foods high in vitamin C are likely to prevent cancer of the esophagus. Foods high in dietary fiber have long been known to lower the risk of colorectal cancer.
Among berries, strawberries and raspberries are known to be especially rich in the natural phenol antioxidant ellagic acid. In laboratory studies, ellagic acid was found to prevent cancers of the bladder, lung, skin, esophagus and breast. Plus, research suggests that ellagic acid likely utilizes several different cancer-fighting methods at once, including its ability to act as an antioxidant.
Ellagic acid is also known to help the body to deactivate certain carcinogens and slow the reproduction of cancer cells. In addition to these properties, studies have found that strawberries contain a broad range of flavonoids that offer yet another tier of anti-cancer strategies.
Identifying cancer-fighting components within strawberries
A study published in the Journal of Agriculture and Food Chemistry focused on identifying the means by which fruit extracts or their components provide protection against human liver cancer cells. Among the compounds tested, quercetin was found to be the most active polyphenol, with a significant reduction in cancer cell viability of up to 80 percent after only 18 hours of treatment. Effective cell death from strawberry extract was also found to be dose- and time-dependent.
Strawberries and their major phytonutrient, quercetin, were also found to slow the normal cell cycle prior to cell death, suggesting that the protective actions may occur along different phases of cancer cell development. As a flavonoid, quercetin is known to exhibit anti-inflammatory and antiviral properties, as well as anti-cancer capabilities.
Previous studies have linked quercetin to prevention or slowing of other types of cancer, including ovarian, breast, colon, leukemia and lung cancer. This more recent study not only supports earlier findings, but sheds new light on the molecular mechanisms taking part in programmed cell death, paving the way for future studies of anti-cancer effects of strawberries and other foods.