by Vitamin D is famously known as the sunshine vitamin, as it can be synthesized in adequate amounts in the skin via sunlight exposure. Vitamin D plays a vital role in nerve function, muscle contraction, immune function, and normal cellular function, with higher vitamin D intake being associated with lowering the risk of depression, cognitive impairment, Parkinson’s disease, breast cancer, hypertension, diabetes mellitus, autoimmune diseases, and flu.
Vitamin D deficiency (VDD) has recently become India’s most prevalent micronutrient deficiency, with deficiency rates as high as 50 – 90% in the general public. Low serum vitamin D levels’ most commonly known side effect is reduced calcium absorption and decreased bone mineral density, leading to rickets, osteoporosis, and osteomalacia. Vitamin D deficiency is also associated with inducing muscle pain, fatigue, anxiety, depression, poor immune function, and frequent illnesses. Chronic vitamin D deficiency can also lead to serious adverse consequences.
Various factors can be the reason for the deficiency, such as reduced sun exposure, reduced dietary intake, reduced availability of fortified foods, increased usage of sun-protective clothing and sunscreen, skin color, geographical location (latitude), and urbanization. Breastfed babies, older adults, people with darker skin color, limited sun exposure, and fat malabsorption are at a higher risk for developing VDD.
Assessment of serum 25(OH)D is used to establish blood levels of vitamin D. Cut-offs for serum levels are classified as: sufficient (30-100 ng/ml), insufficient (<29 ng/ml), and toxic (>150 ng/ml). Inadequate levels are further classified as vitamin D insufficiency (serum levels 20-29 ng/ml) and vitamin D deficiency (<20ng/ml). Vitamin D deficiency is primarily underdiagnosed and undertreated due to the lack of clinical manifestation; therefore, serum 25(OH)D should be measured once a year, and people at risk should evaluate their levels once in six months.
Oral cholecalciferol (D3) supplementation, fortified food intake, and sun exposure are the most efficient ways of treating and preventing VDD. In the case of deficient levels, high-dose cholecalciferol supplementation followed by a maintenance dose is considered the gold standard of treatment: Adults should take 50,000 IU vitamin D supplement once a week for eight weeks, followed by maintenance therapy of 1500-2000 IU/day to prevent deficiency. While children are given 50,000 IU once a week for six weeks, followed by maintenance therapy of 400-1000 IU/d to achieve and maintain serum 25(OH)D levels above 30ng/ml.
Consumption of fortified food and sunlight exposure can help improve the daily vitamin D uptake. Vitamin D-fortified cereals and milk should be introduced as a part of the daily dietary routine for maximum benefit. Sun drying leaves and seafood (fish and fish bones) and exposing mushrooms to sunlight for at least 20-30 minutes will help to improve the vitamin content in these food items and can be a more economical option. Sun exposure might darken the mushrooms and leaves, but it doesn’t affect the taste and
Research identifies solar noon (when the sun is at its apex), usually around 12:00-2:00 pm, as the best time for exposure. However, since the intensity of the rays is harsh during this time, one should practice safe sun exposure techniques. Adequate hydration, covering one’s face and head with a moist towel, and sun exposure in moderately shaded areas can help avoid the harmful effects of intense sunlight. At the onset of any skin irritation or signs of heat intolerance, one should immediately remove themselves from the harsh rays. Sun exposure by exposing the maximum surface area of skin (backs/chest, arms, and legs) for at least 20-30 minutes/ day at least five times a week will help prevent insufficient vitamin D levels.
In summary, a large volume of research suggests a high prevalence of vitamin D deficiency across all ages, genders, and races. Vitamin D levels should be assessed at least once a year and based on the serum levels, a plan of action should be decided with the help of a physician to treat hypovitaminosis D.
Author:Ms. Ansa Saju
Ph.D. Scholar (Sports Nutrition),
Sri Ramachandra Institute of Higher Education and Research,
Chennai
Member of Community Nutrition Forum, Kerala
