Vitamin D is related to calcium absorption by the body, and its deficiency leads to rickets and osteomalacia. In our part of the world rickets is seen in children who are not exposed enough to sunlight which is a rich source of vitamin D. In crowded areas of Kathmandu such as Asan and Indrachok where there may not be enough play areas for exposure to sunlight, rickets may develop more easily. The child may develop a pigeon chest, a crooked spine and become bow legged.
Osteomalacia, on the other hand, is the adult form of childhood rickets and is seen usually in women of child-bearing age mostly in the first pregnancy. Similar to rickets, mothers living in areas with poor exposure to sunlight are vulnerable to this disease. The pelvic bones and ribs may become soft and deformed with a significant pain. The gait may also change. Even without tests for vitamin D level which are expensive to perform and may not be routinely available, rickets and osteomalacia have to be kept in mind when patients present with the above symptoms as vitamin D and calcium can be easily prescribed and more generous exposure to sunlight can be strongly suggested.
For both of these conditions, prevention is possible with adequate exposure to sunshine, and diet which includes fish (a rich source of vitamin D) and vitamin D-fortified food (milk) for mothers and young children. Importantly, many elderly people with inadequate amounts of vitamin D have been known to be susceptible to bony fractures. Even to avoid these kinds of fractures, it is best to have enough sun exposure for this vulnerable age group. Taking vitamin D supplements may also be very useful in the elderly age group of people besides mothers and young children as discussed above.
Lately, vitamin D is in the news not just because an ex-prime minister of Nepal reportedly has the condition, but also because some studies have shown it may be important as an adjunctive (add-on) treatment for tuberculosis, and prevention of certain forms of cancer. Even cardiovascular diseases like hypertension may increase with vitamin D insufficiency. However, the importance of the exact physiologic role of vitamin D, if any in these non-skeletal diseases has not been clarified with any evidence-informed proof. But there are many ongoing studies attempting to show the usefulness of vitamin D for other causes besides the prevention and treatment of bony fractures, rickets and osteomalacia.
An example of this is a recent major study published in JAMA (Journal of the Medical Association) led by David Murdoch from New Zealand who is a frequent visitor to Patan Hospital where he is closely working with the paediatric department to help with the treatment of pneumococcal bacterial diseases in young children. This JAMA study is a well-conducted trial in New Zealand to see the efficacy of vitamin D in the prevention of upper respiratory tract infection (URTI). Murdoch and his team gave adequate doses of vitamin D to healthy adults to see if this would prevent the problem. Unfortunately, it did not. This study was published in a major journal, and one reason for this publication may be the optimistic outlook by the medical establishment on vitamin D supplements.
But for now, all Nepalis can start with enjoying the free sunshine available to us to prevent vitamin D deficiency.
Vitamin supplements, Buddha Basnyat