Vitamin D and B12 Deficiency: Why So Many City Dwellers Are Running Low

"Doctor, I am tired all the time." It is one of the most common things I hear in OPD. Many of these patients have normal sugar and thyroid reports — and then their vitamin D or vitamin B12 level comes back low. Despite plenty of sunshine in India, studies have repeatedly found deficiency of both vitamins to be common, especially in cities.

Why Is Vitamin D Low in a Sunny Country?

Our skin makes vitamin D when it is exposed to sunlight. City life gets in the way of that:

• Indoor routines — office hours, commuting in closed vehicles and evenings at home mean very little direct sun on the skin.
• Covered skin and sunscreen — both reduce how much vitamin D the skin can make.
• Darker skin tones need longer sun exposure to produce the same amount.
• Diet — few common Indian foods are naturally rich in vitamin D.

Why Is B12 Low?

Vitamin B12 comes almost entirely from animal foods — milk, curd, eggs, fish and meat. People who follow a strict vegetarian or vegan diet are at higher risk. Long-term use of some medicines, such as metformin (for diabetes) and acid-reducing tablets, can also lower B12 absorption, as can increasing age.

Symptoms to Watch For

Low vitamin D may cause:

• Generalised body ache, back pain or bone pain
• Muscle weakness or cramps
• Fatigue

Low vitamin B12 may cause:

• Tiredness and breathlessness (from anaemia)
• Tingling, numbness or "pins and needles" in the hands and feet
• Poor memory, low mood or difficulty concentrating
• A sore, smooth tongue or mouth ulcers

These symptoms overlap with many other conditions, which is why a blood test — not guesswork — is the right way to confirm the cause.

Testing and Treatment

Both levels can be checked with a simple blood test. If they are low, treatment usually involves supplements by mouth, and sometimes injections for significant B12 deficiency. The dose and duration depend on how low the level is, so it is best done under supervision — very high doses of vitamin D taken without monitoring can be harmful.

Simple Everyday Habits

• Spend some time outdoors in daylight on most days, with arms and face uncovered where practical.
• Include dairy, eggs or fortified foods if your diet allows.
• If you take metformin long term, ask your doctor whether a periodic B12 check is needed.

This article is for general information and awareness only. It is not a substitute for a consultation, diagnosis or treatment by a qualified doctor. Please do not start, stop or change any medicine without medical advice. In an emergency, call 112 or go to the nearest hospital.