Vitamin D Deficiency: Symptoms, Test and Treatment

What vitamin D does in the body

Vitamin D helps the body absorb calcium from food, which keeps bones and teeth strong. It also supports muscle strength, the nerves, and the immune system. When levels stay low for months, the body starts taking calcium from the bones, and muscles and bones begin to ache.

Unlike most vitamins, the body makes most of its vitamin D in the skin when it is exposed to sunlight. Food provides only a small part of what we need.

Why it is so common in Pakistan

It surprises many patients that a sunny country has so much vitamin D deficiency. Studies in Pakistan have repeatedly found low levels in a large share of adults, and especially in women. The main reasons are everyday ones:

• Little skin exposed to the sun. Most of the day is spent indoors, at home, in offices, schools or shops, and clothing usually covers the arms and legs outside.
• Darker skin. Skin with more melanin needs longer in the sun to make the same amount of vitamin D.
• Diet. Very few everyday Pakistani foods are rich in vitamin D, and fortified foods are not widely used.
• Pollution and haze. Dust and smog cut down the sunlight that reaches the skin.
• Pregnancy and breastfeeding. The mother's needs go up, and the baby depends on her levels.
• Age and weight. Older adults make less vitamin D in the skin, and people who are overweight tend to have lower blood levels.

Common symptoms of low vitamin D

Many people with low vitamin D feel nothing at first. When symptoms appear, they are often vague and easy to blame on a busy life:

• Tiredness and low energy that does not improve with rest
• Aches in the lower back, legs, hips or ribs
• Muscle weakness or cramps, and difficulty climbing stairs or getting up from a chair
• Pain in the bones when pressed, for example the shins
• Low mood
• Hair fall, which has been linked with low vitamin D, although it has many other causes too
• Frequent colds and infections in some people

In children, long-term deficiency can cause rickets: bowed legs, delayed walking, weak teeth and poor growth. In adults, severe deficiency softens the bones (osteomalacia) and, over the years, raises the risk of thinning bones (osteoporosis) and fractures, particularly in older women.

These symptoms can also come from anemia, thyroid problems, diabetes and other conditions. That is why a proper check is better than guessing. See the guide on the CBC blood test for how anemia is checked.

Who should get tested

• Anyone with the symptoms above that have lasted for weeks
• Pregnant and breastfeeding women, and women planning a pregnancy
• Older adults, especially those who rarely go outdoors
• Children with delayed walking, bowed legs or poor growth
• People with kidney or liver disease, or conditions that affect how food is absorbed
• People taking long-term medicines that affect vitamin D, such as some epilepsy medicines or steroids

The vitamin D test

The test is a simple blood test called 25-hydroxy vitamin D (often written as 25(OH)D or 25-OH vitamin D). No fasting is needed. Most laboratories in Karachi give results within a day or two.

Results are reported in ng/mL or nmol/L. Laboratories use slightly different cut-offs, but a commonly used guide is:

Your doctor reads the number together with your symptoms, age, and other results such as calcium, so one number alone does not decide the treatment.

How vitamin D deficiency is treated

Treatment is usually simple, but the dose should be decided by a doctor after the test. The right amount depends on how low the level is, your age and weight, whether you are pregnant, and your other health conditions.

• Replacement course. For a clear deficiency, a doctor usually prescribes a higher dose of vitamin D3 for a few weeks, as tablets, capsules, drops or sachets.
• Maintenance. After that, a lower regular dose keeps the level normal, especially if the reasons for the deficiency have not changed.
• Calcium. Some patients also need calcium, depending on diet and bone health.
• Follow-up test. A repeat test after about three months shows whether the treatment has worked.

Most people notice less tiredness and fewer aches within a few weeks, although bone pain can take longer to settle.

Sunlight: how much is enough

Safe sunlight is free and helps, but it is rarely enough on its own to correct a deficiency that already exists. It is more useful for keeping levels up afterwards.

• Short periods of sun on the face, arms or legs a few times a week help the skin make vitamin D.
• People with darker skin need longer than people with fair skin.
• Sunlight through a window does not work, because glass blocks the rays that make vitamin D.
• In Karachi's strong sun, avoid burning and heat exhaustion. Short, regular exposure is better than long hours in the midday heat, and elderly people and children need extra care.

Foods that contain vitamin D

Food helps, but it cannot fix a deficiency by itself. Good sources include:

• Oily fish such as salmon, sardines, mackerel and tuna
• Egg yolks
• Fortified milk, yoghurt, cereals or cooking oils, where available (check the label)
• Liver, in moderation
• Cod liver oil

Preventing it from coming back

• Keep taking the maintenance dose your doctor recommends
• Get some safe sunlight on most days
• Include vitamin D foods and enough calcium in the diet, such as milk, yoghurt and cheese
• Stay active; walking and light exercise keep bones and muscles strong
• Recheck levels as advised, especially during pregnancy or if symptoms return

How Hiba Care Clinic can help

Dr. Fanila Adhi sees many patients, especially women, whose tiredness, body aches or hair fall turn out to be low vitamin D. At the clinic she will ask about your symptoms, examine you, and suggest only the tests that make sense, usually vitamin D with a CBC and sometimes calcium or thyroid tests. Once the results are back, she explains them and prescribes the right dose.

If you already have a vitamin D report, you can share it in an online consultation over WhatsApp. Women who prefer a female doctor can read more about women's care at Hiba Care Clinic. Elderly patients who cannot travel can be seen through a doctor home visit.

Common questions