Vitamin D is essential for maintaining healthy muscle and strength, but because of its limited availability, a global health crisis has emerged affecting both children and adults.
Unlike most vitamins, vitamin D is not widely available in food. Our bodies produce the majority of it — about 70–80 per cent — when our skin is exposed to sunlight, specifically UV-B rays. However, several factors such as season, latitude, time of day, skin colour, age, and sunscreen use can influence how much vitamin D our bodies can make.
Why vitamin D matters
Vitamin D helps the body absorb calcium from the food we eat and supports proper bone development, renewal, and mineralisation. In children, severe deficiency can lead to rickets, a condition that causes bone deformities. In adults, low vitamin D levels can worsen osteoporosis, weaken bones, and lead to osteomalacia, a painful condition caused by softening of the bones.
Research has concluded that low levels of vitamin D are also associated with a higher likelihood of developing more than one of several diseases such as some types of cancers, cardiovascular disease, multiple sclerosis, rheumatoid arthritis, and type 1 diabetes. Sufficient vitamin D is required during pregnancy; otherwise, children may develop lower levels of bone density and may be at greater risk of developing osteoporosis as they grow older.
How much vitamin D
do we need?
According to health professionals, children and young adults require 200 IU/day (5 µg), older adults require 400-600 IU/day (10-15 µg), and seniors (aged 60 and older) require 800-1000 IU/day to maintain bone health and avoid falling. Sun exposure provides the majority of vitamin D for most people; generally, 10 to 20 minutes of direct sunlight on your skin (face, hands, and arms) before 10 am and after 2 pm is enough for most people to get adequate vitamin D.
Food sources and fortified options
Only a few foods naturally contain vitamin D. These include certain oily fish, eggs, mushrooms, and cod liver oil. To help bridge the gap, many commonly consumed foods, such as breakfast cereals and orange juice, are fortified with vitamin D.
Managing osteoporosis
For many patients diagnosed with osteoporosis, combining calcium and vitamin D may improve bone density and support treatment. Some patients may need injectable medications that are given daily or every six months to rebuild bone density.
(The author is HOD and consultant - orthopaedic & robotic joint replacement surgery at a Bengaluru hospital.)