Study: Broccoli Effectively Protects Skin Against Damaging UV Radiation

Broccoli is rich in compounds that fight off cancers of the lung, breast and prostate gland, and is protective against heart disease and stomach ulcers. A new study published this week in the Proceedings of the National Academy of Sciences reports that broccoli can also be effective in fighting skin cancer.

Paul Talalay and his colleagues in the pharmacology department at Johns Hopkins University, found that broccoli extracts protect skin against UV damage when applied topically. They applied broccoli extracts to the skin of volunteers, and then over the course of the next few days exposed them to UV radiation. The individuals with the broccoli extract had over one third less skin redness and inflammation (which are signs of skin damage that are known to be associated with skin cancer later in life) than unprotected individuals. Interestingly, the broccoli extracts were effective after they had washed away because the broccoli actually turned on key genes in the skin cells, which increased production of UV-protective enzymes.

So, what is the compound in broccoli that is so effective in fighting cancer? In a word, sulforaphane. In 1992, Talalay, showed that sulforaphane - a substance produced by the body from a compound in broccoli - could trigger the production of phase II enzymes. These enzymes are among the most potent anti-cancer compounds known, and can detoxify cancer-causing compounds.

Since the early 1970s the consumption of broccoli has risen consistently within the US. However, US doubled from 3.1 to 6.0 pounds per capita. Broccoli sprouts have an even higher concentration of this compound than does regular broccoli. Other cruciferous vegetables such as brussel sprouts, bok choy, and cabbage can also contain some sulphoraphane, but not as much as broccoli or broccoli sprouts.

One million Americans annually are diagnosed with skin cancers, which can be directly linked to UV radiation. While this study does not prove that broccoli extracts actually prevent UV induced skin cancer, it does show that broccoli extracts offer protection against this potent carcinogen. While the chlorophyll in the broccoli extracts gave research volunteers a green tint, the pigment will not be present once the broccoli extract is synthesized.

A positive side to this study is that the broccoli does not have to be consumed, which is good news for many Americans who do not like this vegetable.

Source: http://www.pnas.org/cgi/content/abstract/0708710104v1