- Ms. Suruchi Gupta
Vitamin D deficiency: Another pandemic
We all at some point in time might have got our blood tests done, and may have been shocked to see the extremely low levels of vitamin D in our body. Your doctor may have prescribed some supplements, which some of us may have taken diligently, while some of us may still be confused as to why do you have such low levels of vitamin D despite following a healthy diet and spending enough time in sunlight.
If you're still confused, let's learn about this vitamin in detail!
Vitamin D is a nutrient that we get from the food we eat as well as a hormone that our bodies make for its different functional roles. It is a fat-soluble vitamin helpful in the absorption of calcium and phosphorus, which are critical in building bones. Most of the body's organs and tissues have receptors for Vitamin D, which suggests its importance in the body beyond bone health. Studies have shown its important role in boosting immunity, blood glucose regulation, reduction of body fat percentage as well as warding off depression to name a few.
Vitamin D exists in two forms: Vitamin D2 and D3. Vitamin D2, also known as ergocalciferol, comes from fortified foods, plant foods (mushrooms), and over-the-counter supplements. No milk and milk products contain vitamin D unless they are fortified. Vitamin D3, also known as cholecalciferol, comes from fortified foods, animal foods (fatty fish, cod liver oil, eggs, and liver), supplements, and can be made internally when your skin is exposed to ultraviolet radiation from the sun.
Now coming to the most important question of the main reasons that make you deficient in Vitamin D. The primary factors contributing to vitamin D deficiency among Asian Indians are increased skin pigmentation, consumption of a vegetarian diet, and limited exposure to sunlight. Indian skins are darker and have comparatively higher melanin, which protects us from UV damage and at the same time acts as a barrier in natural vitamin D production. Cover-up clothing and sunscreen usage, together with being homebound further decreases the absorption and hampers endogenous synthesis of vitamin D. Additionally, impaired fat metabolism in the body, or the presence of diseases of kidney/liver and obesity affect the vitamin D activation and utilization in the body. An important factor leading to ever-growing cases of vitamin D deficiency is the increasing levels of air pollution that affects the penetration of sunlight to reach the earth's surface and our skin.
Levels of serum 25-OH Vitamin D < 20 ng/mL are considered deficient, 20-32 ng/mL are insufficient, and levels 50-100 are considered normal. Signs and symptoms of a Vitamin D deficiency include depression, body aches and pains, fatigue, weakness, hair loss, persistent or frequent infections, and excessive sweating. Vitamin D deficiency may often go unrecognized, and many who see their doctor for aches, pains, and fatigue end up being misdiagnosed. The deficiency retards calcium off the skeletal collagen matrix, resulting in aching bones.
Adults need at least 600 IU/day of vitamin D through diet/and or supplementation. Exposing your skin to sunlight for a short duration will make all the vitamin D your body can produce in a day. Vitamin D production is higher when a larger area of the skin like the back, rather than a small area like the face or arms is exposed. Studies say that the best time to expose oneself to the sun is between 11 am to 2 pm for the maximum synthesis of vitamin D. Fatty variety of fish like sardines, salmon, mackerel, tuna are rich dietary sources of vitamin D. From a diet perspective, it is important to include calcium-rich foods like dairy, green leafy vegetables, okra, broccoli, etc. that further improves vitamin D metabolism. Intake of highly salty food, excessive caffeinated (tea/coffee) and carbonated beverages, and alcohol intake also causes calcium loss from bones, which needs to be avoided. Additionally, it is important to remain physically active at least 4 times a week for 30-60 minutes which keeps the vitamin D level in sufficient range.