Exposure to direct sunlight is important to our health and well being..... according to an increasng body of medical research.
A lack of exposure to direct sunlight represents a health risk to older people confined inside, people working in long hours in offices, and people living in higher and lower latitudes, compounded by the fact that in recent years were we have all be exorted to avoid sun exposure, cover up and SLIP SLOP SLAP on sunscreen, for fear of skin cancer.
The Vitamin D Story
Vitamin D, necessary for good health, is made in the skin with the help of sunlight. However, new research suggests, sunlight may confer another surprising, can be released by UV light, to great benefit for blood pressure and the cardiovascular system.
Vitamin D has several important functions, including helping to regulate calcium and phosphate in the body to keep bones and teeth healthy. It is also important for good overall health and is an important factor in making sure your muscles, heart, lungs, brain and immune system work well. Vitamin D is particularly important in children, pregnant and breastfeeding women.
In recent years, studies have linked vitamin D deficiency to a growing number of health concerns including heart disease, multiple sclerosis, Parkinson’s disease, stroke, diabetes, osteoporosis, prostate disease, some auto immune conditions and depression.
Sunlight is our main source of vitamin D and requires bare skin and direct sunlight to work Experts recommend we aim for 15 to 20 minutes of sun exposure a day, after which we should cover up or apply sunscreen. People with lighter skin may need less exposure than those with darker skin but everyone should be careful not to burn.
Most people should be able to get all the vitamin D they need by eating a healthy balanced diet and by getting some summer sun.
Not so everywhere. From October to April, 90% of the UK lies above the latitude that permits exposure to enough ultraviolet B light necessary for vitamin D synthesis.
However, you can also get vitamin D from supplements and a small number of foods such as liver, oily fish and eggs are also good source of vitamin D, however, you would need to eat an enormous amount to keep your levels in the desired range. The farmed fish typically consumed in the UK may contain less vitamin D content than wild fish and in the UK, cows’ milk is generally not a good source of vitamin D because it isn’t fortified as it is in other countries.
Vitamin D for cancer prevention?
In a well publicised study published in April 2016, researchers at the San Diego School of Medicine reported that higher levels of vitamin D (specifically serum 25-hydroxyvitamin D) were associated with a correspondingly reduced risk of cancer in women. The findings were published in PLOS ONE and can be read in full here. In 1980, 30 years earlier, one of the authors, Cedric Garland and his late brother, Frank, made the first connection between vitamin D deficiency and some cancers when they noted ‘populations at higher latitudes (with less available sunlight) were more likely to be deficient in vitamin D and experience higher rates of colon cancer.’ Subsequent studies by the Garlands and others found vitamin D links to other cancers such as breast, lung and bladder.
The new PLOS ONE study pooled analysis from two previous studies to obtain a larger sample size of over 2,300 women. The only accurate measure of vitamin D levels is a blood test and in this study, the researchers were looking for a greater range of blood serum levels of 25-hydroxyvitamin D or 25(OH)D. What they found was that women with 25(OH)D concentrations of 40 ng/ml (100nmol/L) or greater had a 67 percent lower risk of cancer than women with levels of 20 ng/ml (50nmol/L) or less.
What does this mean?
In the study, Garland and co. do not state whether the raised vitamin D levels should come from sunlight exposure, diet or supplements but they do state that an effort to increase vitamin D in the general population to a level of 40 ng/ml(100nmol/L) would likely and substantially reduce cancer incidence and associated mortality.
Recommended healthy blood serum levels of vitamin D have been a source of vigorous debate in recent years. In 2010, the Institute of Medicine (IOM) concluded that levels lower than 12 ng/ml (30nmol/L) represented a vitamin D deficiency and recommended a target of 20 ng/ml, (50mmol/L) which could be met in most healthy adults (ages 19 to 70) with the equivalent of 600 International Units of vitamin D each day.
Vitamin D may not be all the benefit we get from the Sun
Sunlight may confer another surprising benefit too according to Dermatologist Richard Weller and his team,. New research by his team shows that nitric oxide, a chemical transmitter stored in huge reserves in the skin, can be released by UV light, to great benefit for blood pressure and the cardiovascular system.
What does it mean? Well, it might begin to explain why Scots get sick more than Australians ...
Increasing your exposure to sunlight does not necessarily mean a day at the pool or beach, but if it does, then what better than to
