Blueberries, (Vaccinium angustifolium for wild blueberries or Vaccinium corymbosum for cultivated blueberries) are found throughout North America and have been heralded as one of the most antioxidant-rich foods that may decrease the risk of several chronic diseases, including cancer. Blueberries are most abundant in late spring and early summer, with the Wild blueberries being smaller and sweeter, while farm-raised blueberries may be twice the size of the wild. They are a “hot” item now, being available all year long in most groceries.
Although blueberries contain numerous phytonutrients, it is the compounds that impart the beautiful blue color that are the most beneficial with regards to cancer prevention: anthocyanins. Anthocyanins are found in a variety of fruits and vegetables, and are responsible for the intense red, blue, and purple hues of foods like apples, blueberries, and red cabbage. Anthocyanins are potent antioxidants, possessing the ability to seek out and dispose of cell-damaging free-radicals, preventing DNA damage. Additionally, anthocyanins may prevent or slow the growth of cancer cells, as well as lead to death of cancer cells. Anthocyanins have also been shown in laboratory experiments to stop the ability of cancer cells from spreading by blocking a protein known as matrix metalloproteinase, a compound that degrades tissues surrounding tumor cells allowing them to spread. Blueberry anthocyanins decrease the growth of colon, prostate, liver, melanoma and breast cancer cells in both laboratory and animal testing.
Blueberries contain other compounds that possess anticancer activity as well. Chlorogenic acid, quercetin, petunidin, malvidin, cyanidin, triterpenoids, ursolic acid and resveratrol can all be found in blueberries. Resveratrol is a compound most people have heard of as it is the potent antioxidant found in red wine.
Anthocyanins administered in the form of black raspberry powder, were shown to decrease cancer cell growth and increase cancer cell death in 25 patients with colon cancer given before surgery. Biopsies of the colon tumors were taken before and after administration of the anthocyanin supplement which showed damage to colon cancer cells but not normal cells, suggesting that anthocyanins can slow the growth of colon cancer in humans. Since anthocyanins are found in high amounts in blueberries it remains plausible that blueberries may prevent colon cancer; however, further research is needed to confirm this.
At the end of the day, blueberries are an easy way to increase the phytonutrient load in your diet by adding to smoothies, muffins, desserts, or eaten by the handful as a quick snack.
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