Are you getting enough sun?
Gone are the days of rubbing on the baby oil and lying out in the sun—for most of us anyway. These days, Australians are more aware of the damaging effects of the sun than they have ever been. Living in Australia, we’re lucky to have such beautiful sunny weather, but this can come at a cost if we don’t take the right precautions.
However, we may have taken the ‘slip slop slap’ message a little too seriously. Covering up, slapping on the sunscreen, and staying away from sunlight completely may just have its own risks—we’re talking about vitamin D!
What is vitamin D?
Commonly thought of as the sun vitamin, it’s a fat-soluble vitamin formed in the skin after exposure to UV rays from sunlight. So getting some daily sun is your best source. However, vitamin D can also be obtained from your diet.
Why do I need it?
Vitamin D has many important roles in the body. Low levels of this D-lightful nutrient are linked to many health problems, including multiple sclerosis, osteoporosis, osteoarthritis, rickets, heart disease, diabetes, depression and many forms of cancer.
Osteoporosis-related fractures are more common during the winter months (less sunlight exposure), when muscles tend to be weaker and there’s an increased risk of falling. A study performed by Dr Michael Holick, author of The Vitamin D Solution, found there was a 72 per cent reduction in the risk of falls in his survey population on 800 IU dose of vitamin D for just five months.
Sunshine also suppresses hormones like melatonin, which cause that sluggish feeling. It used to be thought that these hormones originated in the hypothalamus, but now scientists believe this takes place in your skin cells. Sunshine really does put a smile on your face!
You are at a higher risk of deficiency if you are older, spend more time indoors (working, watching TV, playing video games etc), live in a capital city, have a darker skin tone, are overweight, or cover up most of the time.
The cancer connection
The sun’s UV radiation is both a major cause of skin cancer and the best source of vitamin D—talk about your catch 22! To get the vitamin D without the risk of skin cancer, it’s important to find the balance between not enough sun and too much sun.
At least two in three Australians will be diagnosed with skin cancer before the age of 70, but avoiding sunlight doesn’t seem to be the answer. If we take a look at Navy personnel between 1970 and 1980, the same pattern exists: people who worked in jobs that kept them outdoors had the lowest rates of melanoma; and those with indoor jobs had the highest rates. The key to saving yourself from skin cancer as well as avoiding the health risks of low vitamin D is sensible sun exposure (more on this later).
And it’s not just skin cancer that appears to be associated with vitamin D. Women who are deficient in vitamin D at the time of breast cancer diagnosis are nearly 75 per cent more likely to die from the disease compared to women with adequate vitamin D levels. Better survival rates have also been shown in prostate and colon cancer. Vitamin D becomes activated by your liver and kidneys, which inhibits the growth of abnormal cells in the body.
How much sun is too much sun?
So what does sensible sun exposure look like?
Experts believe you need 25 micrograms (1000 IU) of vitamin D per day to maintain healthy blood levels. Short exposure to your arms and legs on most days is best for maintenance. Get out into the sun for about 10 minutes during the summer months or for 20 minutes during winter. Be aware that the required time for exposure to the sun will vary according to latitude and your skin type.
Where else do I get vitamin D?
Vitamin D is rarely obtained from food, unless you regularly eat oily fish or use fortified products, which are more common in some countries. Newly available vitamin D mushrooms (cultivated mushrooms exposed briefly to a beam of light to stimulate vitamin D production) are a useful source, especially for vegetarians and vegans. If you think you’re at risk of deficiency, you might consider a supplement.
Sue Radd is an Advanced Accredited Practising Dietitian and one of Australia’s leading nutritionists and health communicators. Her most recent book Food as Medicine: Eating for Your Best Health received the Gourmand World Cookbook Award for Best Health and Nutrition Book in the world for 2016.
Category: Physical Health