Vitamin D, often called the “sunshine vitamin,” plays a vital role in maintaining our bone health, immune function and mood regulation. It is primarily produced in the skin through exposure to sunlight. However, during seasons with less sunlight, such as the winter months or in areas where sunlight is limited because of smog, getting enough vitamin D can become challenging. Planning your vitamin D intake during these times can protect you from deficiency.
Understanding Vitamin D
Vitamin D is unique because it functions both as a nutrient and a hormone. It helps the body absorb calcium and phosphorus, essential for strong bones and teeth. It also plays a role in immune function, muscle health and regulating inflammation. The body naturally produces vitamin D when the skin is exposed to ultraviolet B (UVB) rays from the sun, but this synthesis decreases in low-sunlight conditions.
Besides lack of adequate sunlight, people with darker skin, who have higher levels of melanin, cannot produce enough vitamin D from sunlight. Older adults, those with obesity, digestive disorders and kidney disease cannot process enough vitamin D.
How to increase your Vitamin D intake
Even during low sunlight, try to get outside. Although UVB rays are less intense in winter, short bursts of sunlight exposure, typically around 15-30 minutes, can still stimulate vitamin D production. Exposing your face, arms, or legs to sunlight during midday, when the sun is at its peak, is especially beneficial. However, the time needed depends on various factors, including skin tone and geographical location.
Focus on dietary sources like fatty fish like salmon, mackerel, tuna and sardines. Eggs from hens that have been exposed to sunlight are good sources of vitamin D. Try fortified milk, orange juice and cereals. Dairy products like cheese and yogurt contain small amounts of the vitamin. Some types of mushrooms exposed to ultraviolet light, such as maitake and shiitake, contain vitamin D.
When should you take supplements?
Only when you are unable to get enough vitamin D from sunlight or food sources. Vitamin D supplements are available in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is more effective in raising blood levels of vitamin D. Speak to your healthcare provider to determine the right dosage for your specific needs.
The general recommended daily intake for vitamin D varies, but it typically falls within the following ranges:
Adults: 600 to 800 IU (International Units) per day
Older Adults: 800 to 1000 IU per day
Children: 400 to 600 IU per day
Get your vitamin D levels checked, especially if you live in areas with limited sun exposure or have risk factors for deficiency. A simple blood test can measure your vitamin D status, and your doctor can recommend an appropriate supplementation plan based on the results.
(Dr Chatterjee is senior consultant, Indraprastha Apollo Hospitals, New Delhi)