Vitamin B12: Do We All Need To Be Supplementing It?

What is vitamin B12?

Vitamin B12, also known as cobalamin, is a water-soluble vitamin that’s found naturally in animal foods, such as fish, other seafood like clams and oysters, meat, beef liver, eggs, milk, and other dairy products.

Within these foods, vitamin B12 is bound to protein. It’s the enzymes and hydrochloric acid in our stomachs that release it, although it doesn’t stay free for long – it eventually binds with another protein called intrinsic factor, which is produced by the cells in our stomach lining. Binding to intrinsic factor allows vitamin B12 to be absorbed when it reaches the intestines.

Once it’s been absorbed, vitamin B12 goes on to play a number of important roles throughout the body, required for proper nervous system functioning, red blood cell formation, and DNA synthesis. Some of what isn’t used is stored in the liver, but given that it’s water-soluble, excess vitamin B12 can also exit the body in your pee.

What happens if you don’t get enough vitamin B12?

Given the major part it has to play in normal bodily function, not getting enough vitamin B12 can have a significant impact on health. Vitamin B12 deficiency can have symptoms including fatigue and heart palpitations, as well as pale skin and loss of appetite. Some people might also develop something called glossitis, where the tongue becomes red and swollen.

There are also a number of neurological symptoms that can develop with vitamin B12 deficiency, such as numbness or tingling in the hands and feet, muscle weakness, problems with balance and coordination, incontinence, low mood, poor memory, and confusion.

Does everyone need to take a vitamin B12 supplement?

Vitamin B12 supplements might be recommended to people who are at particular risk of being deficient in it. This includes those who consume little to no animal products, such as vegans and vegetarians, though eating plant-based foods that have been fortified with vitamin B12 during processing can help reduce the risk of deficiency.

However, vitamin B12 deficiency isn’t necessarily the result of diet alone. Older adults, people with conditions that might affect their absorption of vitamins – such as pernicious anemia, celiac disease, or Crohn’s disease – or people who’ve had gastrointestinal surgery are also at higher risk of deficiency.

If none of these risk factors apply to you and you’re otherwise healthy, in all likelihood, you don’t need to be taking vitamin B12 supplements. It’s unlikely to do you any physical harm if you do – even at high doses, it’s generally considered to be safe – but it’s not going to provide any benefit if you don’t have a deficiency. Excess vitamin B12 can also come out in your pee, so the main harm that comes from taking it unnecessarily is going to be to your bank account.

There have also been claims that vitamin B12 supplements could help to reduce the risk of heart disease, stroke, and cognitive decline, as well as providing a boost to energy and endurance levels. However, at present, there’s no strong scientific evidence to support that being the case.

If you’re unsure whether you need to take supplements, the best thing to do is speak to a doctor. They’ll be able to run a blood test to get an idea of your vitamin B12 levels and make recommendations based on the results and any underlying conditions you might have. Depending on those factors, someone might be advised to take an oral supplement, injection, or nasal spray containing vitamin B12.

All “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current. 

The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.