Vitamin B12 is a vital nutrient that helps keep your body working well. It’s needed to make DNA, support healthy nerves and blood cells, and keep your brain functioning properly.
Even though it’s so important, many people don’t get enough of it. Older adults, vegetarians, vegans, and people with certain health issues are more likely to be low in B12.
What makes it tricky is that the symptoms of vitamin B12 deficiency can be slow to appear and easy to confuse with other problems. Here are 11 sneaky signs that may suggest you need more B12.
Feeling tired for no clear reason is one of the earliest and most common signs of low B12. This is because B12 is needed to make red blood cells, which carry oxygen around the body. Without enough oxygen, you can feel worn out.
Weakness often goes hand-in-hand with fatigue. If you find everyday tasks like walking up stairs or carrying groceries suddenly feel harder, it might be a sign of low B12.
Pale or slightly yellow skin may also appear. This happens because B12 helps make healthy red blood cells. Without it, your body might not produce enough cells or may make them incorrectly, leading to anemia.
A tingling feeling or numbness, especially in your hands or feet, can signal nerve damage due to B12 deficiency. B12 plays a key role in keeping nerves healthy, so low levels can affect how your body feels.
If you’re feeling clumsier than usual, dropping things or having trouble walking, it could be due to nerve problems caused by a lack of B12.
Look in your mouth. A swollen, red, or smooth-looking tongue could be a sign of glossitis—a condition linked to B12 deficiency. You might also get mouth ulcers or feel pain or pins and needles in your mouth.
Shortness of breath or feeling dizzy—especially after light activity—can happen if your body isn’t making enough red blood cells. Less oxygen is delivered to your muscles and organs, causing these symptoms.
Some people may notice vision changes. In rare cases, B12 deficiency can damage the optic nerve, leading to blurry or distorted vision.
Mental health can also be affected. Low B12 levels may cause mood changes, including depression, irritability, or confusion. B12 helps make brain chemicals that affect how you feel and think.
Though rare, some people with B12 deficiency experience a high body temperature. This usually goes away once the deficiency is treated.
Memory problems, especially in older adults, can also be a sign of B12 deficiency. It can sometimes look like dementia but is actually reversible with proper treatment.
These symptoms can develop slowly and be mistaken for other health issues. That’s why B12 deficiency can go unnoticed without a blood test.
Groups at higher risk include older adults, people who don’t eat animal products, and those with digestive disorders like Crohn’s disease or celiac disease, which affect how nutrients are absorbed.
The good news is that B12 deficiency is both preventable and treatable. You can get B12 from foods like meat, fish, eggs, dairy, and fortified cereals. If you can’t absorb enough from food, your doctor may recommend supplements or B12 injections.
If any of these signs sound familiar, it’s worth speaking with your doctor. A simple blood test can check your B12 levels and get you started on the road to feeling better.
If you care about health, please read studies about why beetroot juice could help lower blood pressure in older adults, and potassium may be key to lowering blood pressure.
For more health information, please see recent studies about rosemary compound that could fight Alzheimer’s disease, and too much of this vitamin B may harm heart health.
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