Vitamins C and E continue to be the darlings of many supplement lovers. But those vitamin superstars are beginning to share their throne with the long-neglected vitamin D, which is finally getting the attention it may have always deserved. Fifty percent of the world’s population is said to suffer from vitamin D deficiency (VDD).
Vitamin D is a fat-soluble compound which exists as D1, D2 and D3 – the latter two being the most common forms. Vitamin D2 is obtained from the UV irradiation of the yeast sterol, ergo sterol and is found naturally in sun-exposed mushrooms. Human beings cannot produce vitamin D2.
Also known as “The Sunshine Vitamin”, vitamin D is produced when the skin is exposed to UV radiation. When UVB light from the sun strikes the skin, we synthesise vitamin D3, and therefore this is the most 'natural' form. Most oil-rich fish such as salmon, mackerel and herring also contain vitamin D3. If you shun the sun, suffer from any milk allergies, or adhere to a strict vegan diet, you may be prone to VDD. Diseases and health problems associated with VDD include:
Skeletal Disease- It is said that along with calcium supplements, vitamin D supplements enhance the absorption of calcium in the gut. They help maintain blood calcium levels to enable the normal mineralisation of bones, which prevents low blood calcium levels that can lead to Tetany. Adequate amount of vitamin D also prevents osteomalacia, osteoporosis and osteopenia. After the age of 45, women in particular should consider taking these two supplements. In middle age and beyond, even a small fall can turn into a major bone fracture.
Cancer- UV-B radiation from the sun is said to be the most important environmental risk factor for non-melanoma skin cancer. Since the sun is the primary source of vitamin D, researchers are investigating what role it plays in skin cancer. It is important to maintain just enough sun exposure to keep your vitamin D levels up, while also protecting your skin from damage. VDD has also been linked with colorectal, prostate, breast and ovarian cancers.
Cardiovascular Disease- Vitamin D deficiency is associated with an increased prevalence of hypertension, hyperlipidemia, peripheral vascular disease, coronary artery disease, heart attack, heart failure and stroke. Anti-inflammatory effects of vitamin D may be the reason for this.
Infection- Low vitamin D levels also tends to affect one’s overall immunity. Observational studies have shown an association between low vitamin D status and an increased risk of both upper and lower respiratory tract infections. The role of vitamin D in reducing the risk of hospital-acquired infections, such as pneumonia, urinary tract infections and surgical site infections, is also being investigated.
Other Issues- Depression, dementia, multiple sclerosis, erectile dysfunction, schizophrenia, diabetes and skin diseases have all been linked with VDD to various extents.
Here Comes the Sun- If you're striving for 1000 IU of vitamin D per day, then supplements or sunlight are the only options. Regular sun exposure can stimulate the human skin to produce quantities of vitamin D that far exceed your needs. Without a shadow of a doubt, sunlight is the best single source of vitamin D for most people. Sun exposure to the arms, legs, back of the neck and spine for 10-15 minutes is generally sufficient. The amount of vitamin D produced depends on the intensity of the UVB in the sun and several other factors.
Don’t Overdo It- The recommended dietary allowance for vitamin D is 600 – 800UI for an adult, which increases after the age of 45. An overdose of vitamin D can lead to kidney damage or kidney stones. So be careful not to overexpose yourself to the sun, and check with your doctor, who can determine your current vitamin D level, and prescribe a regimen that will suit your needs.
- Soumya Kumar, NutriVise, www.nutrivise.wordpress.com