The sunshine vitamin
Mridula Wattas
Vitamin D has always been associated with calcium for building strong bones and for overall healthy growth in children. I vividly remember the advertisements of a few dietary supplements that were available in India while we were growing up. Calcium and vitamin D were the most prominent nutrients in those supplements and their ads always had pictures of healthy children depicting strong bones. Research done in the last decade or so suggests that Vitamin D may also be important for many other reasons outside of good bone health. Some body functions that the vitamin may help include:
- Immune system, which helps you to fight infection
- Muscle function
- Cardiovascular function, for a healthy heart and circulation
- Respiratory system — for healthy lungs and airways
- Brain development
- Anti-cancer effects
Normal levels
The most accurate way to measure how much vitamin D is in your body is the 25-hydroxy vitamin D blood test. Although there are a few major studies carried out in India to determine the optimum (sufficient) levels of serum vitamin D 25 (OH) D to be maintained to prevent chronic ailments, it is suggested that serum 25(OH) D levels above 30 ng/ml are sufficient for a healthy individual.
Till the 1990s, nobody had suspected that a sub-tropical country like India could have vitamin D deficiency. Since vitamin D was sunshine vitamin, it was taken for granted that the Indians would have sufficient amount of vitamin D in their system. There was ample sunlight available in India and Indians were neither over clad nor excessively dark. Later studies showed that up to 70 per cent of adult population in India was vitamin D deficient. This was due to a combination of factors. People were shifting from rural to urban areas, their dietary habits were changing and rising pollution led to unavailability of ample sunshine and more and more urban Indians remained indoors.
Endocrinologists say vitamin D deficiency has no defined symptoms. People who complain of back pain, unexplained muscle pain, general fatigue are most likely to be vitamin D deficient. Vitamin D deficiency can be easily corrected by supplements or some lifestyle changes.
Get sufficient vitamin D by...
- Eating foods rich in vitamin D.
- Taking daily supplements of vitamin D after consulting your doctor.
- Exposure to sunlight for 15-20 minutes.
How to get maximum vitamin D?
Sunlight consists of, among other things, ultraviolet rays A and B. Exposure to UVA rays may lead to malignant lesions in the skin, which is why we are told to wear sun block creams when we are exposed to sunlight. It is the exposure to UVB rays that results in vitamin D production in the skin. So, it is important to know when are UVB rays available during the day.
The trick to getting the most vitamin D out of your daily sun exposure is to sunbathe when your shadow is shorter than your height. Typically, you’ll get the most vitamin D if you go out between 10am and 2pm. That’s about the only window of time when your shadow will be shorter than your height. And that’s when the UVB rays, which are what you need to make vitamin D, are at their strongest.
Don’t wear any sun block or sunscreen when sunbathing. You can apply something organic such as coconut oil on your skin. If you’re fair-skinned or haven’t exposed your skin to the sun for a long period, pay special attention, especially at the beginning, to make sure you never allow your skin to get burned. Start with five minutes daily; increase gradually.
In summers, wear sunglasses to protect the delicate skin around your eyes and drink plenty of water when out. Figuring out how long to stay in the sun to produce sufficient amounts of vitamin D can be tricky business, although as a general rule of thumb, you’d want to expose as much of your body as possible to sunlight until your skin turns the lightest shade of pink. There are some UV/ vitamin D calculators available which can tell how long to expose your skin to UVB rays for.
Do not even try to be exposed to sun light through windows— in your office, your home or your car — you get the UVA but virtually none of the beneficial UVB. Sunlight filtered through window glass increases your risk of a variety of conditions, primarily skin cancer, because the UVA’s are effectively destroying your vitamin D3 levels while you’re getting none of the benefits from UVB.
Getting vitamin D from the sun is essential for making a critical vitamin and hormone that protects you from disease and carries out thousands of major functions in your body every day.
Besides being good for your body, it’s great for your spirit. Have you ever noticed how you feel happier sitting or walking in the sun? Doesn’t just going outside in the sun calm your nerves and lift your spirits?
There’s a reason for this. Your body needs sunlight in the same way it needs nutrients. In addition to the noticeable lift it gives your mood, it also helps lower your blood pressure, cholesterol and blood sugar, improve your immunity, regulate your weight, reverse many chronic diseases, protect you from many cancers and improve your overall health and happiness.
— The writer is former chief dietician, Department of Dietetics, PGIMER
