A new scientific review examines the growing evidence of an inverse relationship between levels of sun exposure and all-cause mortality. Published in the International Journal of Cancer Research and Treatment (IJCRT), the paper notes that women with active sun exposure habits have been estimated to have a 1- to 2-year longer life-expectancy. With such findings clearly being contrary to the advice currently promoted by government health authorities, the review concludes that the introduction of sensible sun exposure recommendations might improve public health.
As the paper describes, sun exposure has traditionally been the main contributor to vitamin D status in humans. When sunlight reaches the skin, vitamin D is produced in the body naturally. However, for forty years now, to protect against ultraviolet (UV) radiation, a known risk factor for skin cancer, government health authorities worldwide have strongly recommended avoiding exposure to the sun.
For protection when skin is exposed to the sun, authorities generally advise use of high factor sunscreen. However, this can essentially nullify the body’s ability to produce vitamin D. As such, it is plausible that sun avoidance and overuse of sunscreen may together have been responsible for a dramatic increase in the number of people with deficient or insufficient levels of vitamin D. Indeed, a clinical review published in 2017 in the Journal of the American Osteopathic Association examined this possibility and drew attention to the startling fact that around 1 billion people worldwide now have inadequate levels of this essential nutrient.
The IJCRT review points out that new emerging data have shown low UV exposure and low vitamin D levels to be related to an increased mortality rate due to skin cancer. In fact, low sun exposure habits in regions of low solar intensity have been shown to constitute a similar major mortality risk factor to that of smoking. Significantly, therefore, research now shows vitamin D deficiency to be closely associated with chronic diseases such as bone metabolic disorders, tumors, cardiovascular diseases, diabetes, neuropsychiatric disorders, and autoimmune diseases. In sharp contrast to their publicizing of the dangers of smoking, however, government health authorities have thus far chosen not to act on these findings.
Particular attention is paid in the IJCRT review to the fact that pre-eclampsia – a condition occurring in pregnancy characterized by high blood pressure, protein in the urine, and often swelling in the feet, legs and hands – and eclampsia, where seizures additionally occur, is a major cause of maternal mortality worldwide. Noting that eclampsia has been shown to be more prevalent during the winter, the paper’s author suggests this may be due to a lack of sun exposure and points out that vitamin D deficiency in late pregnancy is known to be related to an increased risk of pre-eclampsia. Due to the high worldwide prevalence of vitamin D deficiency, the review therefore advises that vitamin D supplements should be recommended in pregnancy.
For anyone who doubts that vitamin D deficiency is a serious global health problem, consider the fact that even in Australia – a country where people typically enjoy an outdoor lifestyle with plentiful sunshine – it has reached crisis levels. Up to seventy percent of Australians are now believed to have deficient or insufficient levels of this nutrient. In the United States and Canada, too, the problem is widespread. Three-quarters of U.S. teens and adults are now thought to be deficient in vitamin D, while two-thirds of Canadians have levels below those that research has associated with a reduced risk of chronic disease.
A similar picture has emerged in Europe, where blood levels of vitamin D are known to be low in up to seventy percent of the population. Pregnant Arab women have been shown to have an “extraordinarily high prevalence” of vitamin D deficiency, with India also home to a growing epidemic of it. Clearly, the world ignores this global health problem at its peril.