When you think about the vitamins you need daily, there may be some all-stars that pop into your mind first — like vitamin D and iron. There are a number of essential vitamins your body needs to perform at its best, and one of those is vitamin B12. This little vitamin has a big job when it comes to your physical and mental stamina. Here’s what you need to know about vitamin B12, including a few red flags that indicate you may be dealing with a vitamin B12 deficiency.
Vitamin B12 is a water-soluble vitamin, meaning when it’s consumed, it dissolves in water, making it easy for your body’s tissue to absorb and use immediately. Unlike other vitamins that are fat-soluble, vitamin B12 isn’t stored in the body in large amounts. The liver can hang on to some vitamin B12, but most excess is removed through urine. Vitamin B12 is consumed, used, and then needs to be replenished through your diet (more on that below!).
As for its function, vitamin B12 helps produce red blood cells (which deliver oxygen throughout the body) and DNA. It also plays a role in the function of the central nervous system and cell metabolism — giving cells the energy they need to go handle essential processes like converting food to energy.
Aside from its ability to help with DNA and red blood cell production, there are some added bonuses vitamin B12 can deliver:
It may help prevent and treat depression. Vitamin B12 affects mood and other brain function, as a 2020 study showed a link between vitamin B12 supplementation and preventing the onset of depression. The same study also found B12 supplement can even improve the efficacy of antidepressants when taken together. However, always consult with your doctor before adding a new supplement to your routine.
Vitamin B12 can boost brain power. Due to its role in the central nervous system, having a vitamin B12 deficiency can lead to cognitive impairment like memory loss or trouble concentrating. Make sure you’re fueling your brain by consuming foods packed with vitamin B12 (check out the list below!).
It’s beneficial during pregnancy. For those who are pregnant, vitamin B12 can help protect your developing baby's central nervous system. You may be advised to eat more vitamin B12-rich foods or take vitamin B12 supplements to prevent birth defects like spina bifida — but remember, always consult with your doctor first.
The National Institutes of Health recommends adults consume 2.4 mcg of vitamin B12 daily. Most of us can easily get that amount in our diet.
Here are some foods with solid sources of vitamin B12 to incorporate into your diet regularly:
Fish (Salmon, clams, and tuna)
Dairy (Milk, Greek yogurt, cheddar, and Swiss cheese)
Fortified breakfast cereals with vitamin B12
Those at-risk for being vitamin B12 deficient are largely vegans and vegetarians since many sources of vitamin B12 are from animal products. Those with certain conditions including Crohn’s disease may also be at risk, due to a lack of stomach acid needed to absorb vitamin B12 from foods.
Symptoms of vitamin B12 deficiency include fatigue, feeling faint, breathlessness, pale skin, and heart palpitations, among other symptoms. Make sure to mention any of these warning signs to a healthcare provider, who may recommend a vitamin B12 supplement to make sure you’re providing your body with enough of it.
About the author
Colleen Travers is a freelance writer and editor who specializes in health, nutrition, diet, fitness, and wellness trends for various publications and brands. Her work has appeared in Reader's Digest, SHAPE, Fit Pregnancy, Food Network, and more.