5 Vitamin B12 Benefits For Men: The Fertility Vitamin

Vitamin B12 improves sexual health in men.

We all know how vital vitamin B12 is for the production of DNA, nerves, and red blood cells. But that’s just the beginning of the story! Just like your brain and immune system, your reproductive organs also need a healthy dose of B12 to stay in good shape. And while the spotlight is often on its role in women’s reproductive health, men also have as much to gain (or lose!) from this vitamin. Here’s a closer look at how vitamin B12 calls the shots in men’s fertility and sexual health.

1. Increases Sperm Count And Sperm Concentration

Vitamin B12 plays an important part in the production and development of sperm. By extension, when you are deficient or have low levels of B12, it can take a toll on your sperm health. Studies show a link between a lower concentration of plasma vitamin B12 and infertility in men.1 B12 supplementation has shown promise and is, in fact, recommended when sperm count is affected. One study found that when 1,500 mcg of methylcobalamin, a form of vitamin B12, was administered daily to infertile men for a period ranging from 4 to 24 weeks, the total sperm count increased in 53.8% cases and sperm concentration increased in 38.4% cases.2 Further research will help firm up how exactly B12 can help and how to increase the success rate.


2. Boosts Sperm Motility

If you have poor sperm motility, your sperm doesn’t swim properly. This can affect its ability to travel to and fertilize an egg, resulting in fertility problems. But vitamin B12 may be able to improve motility in certain cases. In the same study that tested the effect of vitamin B12 supplementation on sperm count, it was found that sperm motility and total motile sperm count increased in 50% of the test subjects.3

3. Prevents DNA Damage In Sperm Cells

If you suffer from varicocele, a condition where the veins in your scrotum get enlarged, you could have a low sperm production and poor sperm quality. In fact, infertile men with varicocele have been found to have the greatest percentage of sperm cells with damaged DNA compared to other infertile groups.


Sperm DNA fragmentation refers to damage in sperm cells. While some amount of sperm DNA fragmentation is normal, a high percentage reduces the chance of a successful pregnancy, particularly with artificial methods like IUI or IVF.

One study looked at the effect of treating infertile men with varicocele with a host of antioxidants including B12 for a period of 3 months. On an average, it was found that patients had 31.3% lesser degraded sperm cells and a decrease of 22.1% in sperm DNA fragmentation after this treatment. The total numbers of sperm cells increased as well.4


4. May Prevent Premature Ejaculation

Statistics indicate that 1 in 5 men experiences premature ejaculation at some point in their lives.5 And this can interfere with a healthy sex life. Research now shows that low levels of vitamin B12 can be a factor associated with premature ejaculation. Making sure that you have adequate levels of vitamin B12 may, in turn, can help you tackle this problem.6

5. May Prevent Loss Of Libido

While B12 may not be the primary reason for loss of libido, it’s worth checking for a deficiency if you have the problem. This is because a vitamin B12 deficiency can result in pernicious anemia, a condition where your body is unable to produce functional red blood cells. And one of the symptoms of pernicious anemia is the loss of libido. If this is indeed what is affecting your libido, consider B12 supplementation rather than trying to source it from food as pernicious anemia hinders your absorption of vitamin B12 from food.7 Loss of libido is also a common fallout of fatigue and depression, and both have been found to have a link with B12 deficiency. Researchers also suggest B12 supplementation, along with folic acid, to relieve symptoms of depression.8


Adults Need 2.4 Micrograms of B12 Daily

On an average, an adult needs 2.4 micrograms of this crucial vitamin per day. And like most vitamins, B12 needs to come from food or supplements since our bodies can’t make it. You can get vitamin B12 from clams, beef liver, milk, eggs, meat, fish, and poultry. If you are already deficient and facing health problems, your doctor may suggest supplements to get back on track.

An estimated 1.5–15% of the population suffers from vitamin B12 deficiency. This includes people with Crohn’s disease, pernicious anemia, or celiac disease, as they often have difficulty in absorbing this vitamin from food. Older people who don’t have sufficient hydrochloric (stomach) acid can also face problems processing the vitamin. Vegans and vegetarians are also at risk of a deficiency since plant-based foods do not contain sufficient amounts of vitamin B12. Here’s a list of vegan sources of vitamin B12. People on antacids or proton pump inhibitors also suffer from B12 deficiency due to suppressed stomach acid.


Vitamin B12 Deficiency Can Affect Both Sexual And Mental Health

A deficiency in vitamin B12 can have a wide range of consequences. Along with fertility and sexual problems, you may experience weakness, tiredness, constipation, megaloblastic anemia, problems with balance, dementia, confusion, depression, poor memory, sore mouth or tongue, loss of appetite, or weight loss. It can even damage the nervous system.9

Vitamin B12 Overdose May Raise Risk Of Colorectal And Lung Cancer

But while you need vitamin B12 to stay healthy, excessive intake can actually be harmful. Some studies have found that increasing the intake of vitamin B12 upped the risk of colorectal cancer in men.10


Another recent study found that taking vitamin B6 and B12 supplements for a long time significantly raises the risk of lung cancer in men, particularly smokers. Researchers speculate that these otherwise protective vitamins might be feeding tumors and causing them to grow faster.11 12 However, it’s unclear whether B12 derived from whole foods rather than supplements would produce a similar effect.

To improve fertility, increase your B12 intake. However, make sure you consult your doctor before opting for supplements as excessive intake may cause more harm than good.