You’ve been tired for months. Your hair is coming out in the shower. Your back aches in the morning, your legs feel heavy by evening, and somewhere along the way you stopped feeling like yourself. You blame work, the commute, the heat, the kids, or just “getting older.” Then a routine blood test comes back and the doctor says two things you didn’t expect: low vitamin D and low B12.
This happens in Indian clinics every single day. A country with plenty of sunshine and a food culture built around dal, dairy and vegetables might seem like the last place to run short of these two nutrients. And yet vitamin D and B12 deficiency in India is one of the most common nutritional problems doctors see, and one of the most overlooked.
This article explains why it happens, which symptoms people brush aside, who is most at risk, and what you can realistically do about it. It isn’t a replacement for a doctor’s advice, but it should help you recognise when it’s time to ask for a blood test.
Why India’s sunshine doesn’t protect us
The common assumption is simple: lots of sun, lots of vitamin D. The reality is messier.
Your skin makes vitamin D when it’s exposed to ultraviolet B rays from the sun. But several things get in the way for a lot of people in India:
- Indoor lives. Office jobs, long commutes in closed vehicles, and gaps between home and workplace mean many people see sunlight only through a window, which doesn’t help because glass blocks UVB.
- Timing. The best UVB exposure is around midday, which is exactly when most people are at their desks or avoiding the heat.
- Clothing and sun protection. Covering most of the body, whether for cultural, religious or comfort reasons, or using sunscreen or umbrellas consistently, reduces how much vitamin D the skin can make.
- Skin pigmentation. Melanin, which gives skin its colour, acts as a natural filter. People with darker skin generally need more sun exposure to make the same amount of vitamin D as someone with lighter skin.
- Air pollution. In heavily polluted cities, particles in the air can scatter and absorb some UV light. Researchers continue to study how big this effect is, but it’s a plausible contributor.
- Few vitamin D-rich foods. Very few foods naturally contain meaningful amounts, and fortified products are not yet part of everyday eating for most households.
Put those together and it’s easier to see why many Indian studies over the years have reported high rates of low vitamin D across age groups, in cities and villages alike. The NHS page on vitamin D gives a clear overview of how the body makes and uses it.
Why B12 runs low too
Vitamin B12 is a different story. Your body can’t make it, and plants don’t produce it. It comes almost entirely from animal foods: meat, fish, eggs, milk and dairy products.
That matters in a country where a large share of people follow vegetarian diets, and some avoid even eggs. Dairy can provide B12, but the amounts vary and many people don’t eat enough of it consistently. People who eat no animal products at all have a particularly high risk.
Diet isn’t the only reason. B12 absorption is a surprisingly delicate process. It needs stomach acid to release it from food, a protein made in the stomach called intrinsic factor to carry it, and a healthy lower small intestine to absorb it. If anything in that chain breaks down, you can eat plenty of B12 and still run low.
That’s why you also see deficiency in people who:
- Take metformin long-term for type 2 diabetes
- Use acid-reducing medicines (proton pump inhibitors such as pantoprazole or omeprazole, or H2 blockers) for months or years
- Have gut conditions such as coeliac disease or Crohn’s disease
- Have had weight-loss or stomach surgery
- Are older, since stomach acid tends to fall with age
- Have pernicious anaemia, an autoimmune condition that stops intrinsic factor being made
The NIH Office of Dietary Supplements fact sheet on vitamin B12 covers food sources, absorption and who is at risk in plain language.
The symptoms people ignore
Here is the tricky part. Neither deficiency usually announces itself with one dramatic symptom. They creep in slowly, and the signs are vague enough to be explained away. These are the ones most often dismissed.
1. Tiredness that sleep doesn’t fix
Both deficiencies can cause fatigue. B12 is needed to make healthy red blood cells, and when levels drop, the blood carries less oxygen around the body. Low vitamin D has also been linked with persistent tiredness in many people. If you wake up feeling as though you never slept, and it’s been going on for weeks, it’s worth testing before assuming it’s stress.
2. Aching bones and a sore lower back
Vitamin D helps your body absorb calcium and keeps bones strong. When levels are very low, adults can develop a condition called osteomalacia, where bones soften. Early on it can feel like a deep, vague ache in the lower back, hips, ribs or legs, or tenderness when you press on a bone. Many people treat this with painkillers for months and never ask why it started.
3. Muscle weakness and cramps
Struggling to climb stairs, getting up from a chair, or feeling heaviness in your thighs can all be signs of low vitamin D. In older adults, weak muscles and poor balance raise the risk of falls, which is one reason doctors pay attention to it.
4. Hair fall and thinning
Hair loss has many causes, so please don’t assume it’s always a vitamin problem. But deficiencies in vitamin D and B12 are among the things doctors check for when someone is shedding more hair than usual, alongside iron and thyroid levels. If your hair fall is sudden, patchy or heavy, get a proper assessment rather than buying a random supplement.
5. Tingling, pins and needles, or numb feet
This one deserves attention. B12 plays a key role in keeping nerves healthy. When it’s low, people often notice tingling or numbness in the hands and feet, a burning feeling, or a sense that their feet don’t quite feel the ground. Many people dismiss it as a “nerve issue,” poor circulation or sitting in one position too long. Left untreated, B12 deficiency can cause nerve damage that doesn’t fully reverse, which is why early testing matters.
6. Brain fog, forgetfulness and low mood
Forgetting words, losing your train of thought, feeling flat or irritable: these are easy to blame on stress or a busy life. Low B12 has been linked with memory and concentration problems, and low vitamin D is often seen in people with low mood, although the relationship between vitamin D and depression is still being studied and isn’t a simple cause and effect. Neither should replace proper mental health care, but a blood test is a reasonable step if you’ve been feeling “off” for a while.
7. Pale or slightly yellow skin, breathlessness and palpitations
B12 deficiency can cause a type of anaemia in which red blood cells are larger than normal and don’t work well. Symptoms include looking pale or faintly yellow, getting breathless on stairs, feeling dizzy, or noticing your heart racing. These deserve a prompt check.
8. A sore, smooth or red tongue and mouth ulcers
A swollen, smooth, beefy-red tongue (called glossitis) and recurring mouth ulcers or cracks at the corners of the mouth can be signs of B12 deficiency. People often assume it’s heat in the body, spicy food or poor dental hygiene.
9. Getting sick often
Vitamin D is involved in how the immune system behaves. If you pick up every cold going round, or infections take a long time to clear, low vitamin D is one of several possible factors. It’s not the only one, so don’t over-attribute it, but it’s worth including in the conversation with your doctor.
10. Balance problems or a wobbly walk
In more advanced B12 deficiency, the nerves and spinal cord can be affected, causing unsteadiness when walking. This is not a symptom to wait on. If it’s happening, see a doctor soon.
Who should be especially alert
Anyone can be affected, but certain groups carry a higher risk:
- Vegetarians and vegans, particularly for B12
- Office workers and people who spend most of the day indoors
- Women, especially during pregnancy and breastfeeding, when needs go up
- Older adults, who absorb less B12 and make less vitamin D in their skin
- People with diabetes on metformin
- People on long-term acid-reducing medicines
- Anyone with a gut condition that affects absorption
- Children and teenagers who spend little time outdoors or have restricted diets
If you fall into one or more of these groups and have symptoms, you have a good reason to ask for testing.
Getting tested: what to ask for
A simple blood test can check both. For vitamin D, labs usually measure 25-hydroxy vitamin D. For B12, it’s a serum B12 level. Reference ranges differ between laboratories, so look at the range printed on your own report and discuss the numbers with your doctor rather than comparing yourself with a figure you saw online.
A few practical points:
- B12 results sitting in the borderline zone can be hard to interpret. Your doctor may order extra tests such as homocysteine or methylmalonic acid to clarify.
- A full blood count can show whether B12 deficiency has started affecting your red blood cells.
- If you’re already taking supplements, tell the doctor, because they can change your results.
It’s also wise to ask about iron, thyroid function and blood sugar at the same time, since symptoms such as tiredness and hair fall overlap with several conditions. You don’t want to treat one deficiency and miss another cause.
What actually helps
Food
Food alone often isn’t enough to correct a deficiency, but it matters for maintenance.
- For B12: Eggs, milk, curd, paneer, fish and meat all contain it. Some breakfast cereals and plant milks are fortified, so check the label. Vegans will almost always need a supplement or fortified products.
- For vitamin D: Fatty fish, egg yolks and fortified milk or oils can contribute, though the amounts are modest. Mushrooms exposed to sunlight contain some vitamin D too.
Sunlight
Sensible sun exposure helps, but it’s not a magic fix, and there’s no single recommendation that suits everyone. Skin type, season, city, time of day and how much skin is exposed all change the result. Short, regular exposure of the arms and legs around midday is commonly suggested, but prolonged sunbathing isn’t a good idea, and skin protection still matters. Ask your doctor what’s reasonable for you.
Supplements
This is where most people go wrong, in both directions: some skip treatment altogether, while others self-prescribe large doses from the internet.
If your levels are low, a doctor will usually recommend a specific dose for a specific length of time, then retest. For vitamin D, that might mean high-dose courses followed by a lower maintenance dose. For B12, it might be tablets, or injections if absorption is a problem or symptoms are neurological.
Two cautions:
- Don’t take mega-doses of vitamin D on your own. It’s fat-soluble, so excess can build up in the body and push calcium too high, which can harm the kidneys and cause other problems.
- Don’t delay treatment if you have nerve symptoms. Numbness, tingling or balance trouble linked to B12 deficiency should be assessed by a doctor promptly, because delay can make nerve damage permanent.
The NIH fact sheet on vitamin D explains both the benefits and the risks of too much. For B12 specifically, the NHS guidance on B12 and folate deficiency anaemia describes how it’s diagnosed and treated.
Follow-up
Treatment isn’t a one-and-done. Most doctors recheck levels after a few months to confirm they’ve improved and adjust the plan. Skipping this step is a common reason people feel better briefly, stop everything, and slide back.
A reasonable way to think about it
It’s easy to fall into one of two traps. The first is dismissing the symptoms entirely: “Everyone’s tired, it’s normal.” The second is the opposite, blaming every ache and every bad day on a vitamin and spending money on supplements without a diagnosis.
The middle path is simpler. If you’ve had several of the symptoms above for more than a few weeks, especially if you’re in a higher-risk group, get tested. If the results are low, treat them properly under medical guidance and recheck. If the results are normal, you’ve at least ruled something out and can look for other causes.
When to see a doctor sooner rather than later
Don’t wait for a routine check-up if you notice:
- Numbness, tingling or weakness in your hands or feet that is spreading or getting worse
- Difficulty walking or loss of balance
- Confusion, severe memory problems or marked changes in mood
- Significant breathlessness, chest pain or a racing heartbeat
- Bone pain along with difficulty walking or a recent fracture from minor injury
- Symptoms during pregnancy, or in a young child, such as delayed development or bowed legs
The bottom line
Low vitamin D and B12 in India is common enough that it’s worth treating as a normal thing to check, not a rare condition. The symptoms are subtle and easy to explain away: the tiredness, the aches, the tingling, the hair on your pillow. But they’re also very treatable once identified.
If any of this sounds like you, book a simple blood test, bring your symptom list, and ask your doctor what the results mean for you specifically. It’s a small step that can make a real difference to how you feel.
Disclaimer: This article is for general information and does not replace professional medical advice, diagnosis or treatment. Always consult a qualified healthcare professional about your symptoms, test results and supplements.
Sources and further reading
- NHS: Vitamin D
- NHS: Vitamin B12 or folate deficiency anaemia
- NIH Office of Dietary Supplements: Vitamin D
- NIH Office of Dietary Supplements: Vitamin B12
