Sunshine = Vitamin D


Vitamin D is an essential part of the body’s arsenal in fighting cancer, so the practice of zealously avoiding exposure to the sun may be contributing to vitamin D deficiency and subsequently to an increased risk of cancer.

Research published in the British Medical Journal (vol. 237, p.316) on multiple sclerosis (MS) suggests that children who were exposed to the sun an average of two to three hours a day in the summer are a third less likely to develop MS.

When the sun’s ultraviolet (UV) rays are absorbed by the skin, a biochemical process begins in which an active form of vitamin D is created. You can also get vitamin D from foods such as oily fish, and to a much lesser extent dairy products, but sunshine is by far our most important source of this essential vitamin. In addition to its role in enabling calcium to be absorbed from the gut, new research is showing that vitamin D stops the out-of-control cell growth that characterizes cancer. A number of population studies are suggesting that the less sunshine we get, the higher our risk is for cancers of the colon, prostate, breast, lung and, believe it or not, skin.

Is Tanning Healthy or Harmful?
How much sun should you get? According to Michael Holick, a researcher and author of the book, The UV Advantage, between 11 a.m. and 2 p.m. in the summer (when the sun is most intense), a Caucasian with medium-fair skin living in Boston needs five to eight minutes of sunshine without sunblock. People who live further north and/or have darker skin need more time and conversely, people who live closer to the equator and have fairer skin need less time.

There is considerable controversy about whether the process of skin tanning is beneficial and protective against the sun’s harmful rays, or whether tanning is actually a symptom of skin damage. Although repeated sunburns are correlated with later skin cancers, people who are brown from spending their lives working outside in the sun do not necessarily have higher rates of skin cancer: factors such as light skin, freckles, numerous moles, genetics and exposure to radiation and arsenic are greater risk factors.

Don’t depend on sunblock to protect you from the harmful effects of the sun. Despite 20 years of widespread sunblock use, the rate of skin cancer in industrialized countries has not declined. This may be partially due to the fact that most sunblock protects against the sun’s UVB rays, but not against the more deeply-penetrating UVA rays, which don’t burn the skin but still damage it.

The bottom line on healthy sunning is to avoid sunburn; in fact, you should be out of the sun long before your skin starts turning red.

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