Key takeaways:
Some supplements — like selenium and coenzyme Q-10 — may enhance male fertility. But the research overall remains fairly limited.
If you decide to take a supplement to boost male fertility, knowing how much to take or for how long may be challenging, since no clear guidelines exist.
Most of the research on supplements for male fertility looks at sperm quality. There’s very little data on whether supplements increase pregnancy rates.
With advancements in reproductive health, there’s a growing interest in fertility, or someone’s ability to have a baby. Specifically, people are interested in ways to enhance it.
Most of the research is still early or mixed. But there’s some evidence that certain supplements — especially some antioxidants — can help. These supplements may protect sperm from cellular damage and maintain the sperms’ health and overall function. This, in turn, may enhance male fertility. But, in many cases, improved sperm quality doesn’t translate to fertility, and it’s not clear why.
Before we dive in, here’s a quick refresher on terms commonly used to describe sperm health:
Motility: How many sperm are moving
Morphology: The shape, size, and appearance of sperm
Density or concentration: How many sperm are in a given amount of semen
Count: How many total sperm are produced
Maturation: A process that gets sperm ready to fertilize an egg
Here’s a look at what the research shows about common supplements for male fertility.
What it is: L-carnitine is a nutrient found in many foods, like:
Red meat
Poultry
Fish
Dairy
Your body uses L-carnitine to produce energy.
It’s thought that L-carnitine helps sperm develop, and that it protects against sperm damage because of its antioxidant effects.
What the research shows: Many small and large review studies support L-carnitine supplementation. Researchers found that men with unexplained infertility, who took between 3 to 9 g daily, saw:
Increased sperm motility and more normal-shaped sperm
Increased sperm concentration, although this data was mixed
Many factors can affect fertility, including sperm count. Check out the 9 most common causes of oligospermia, or low sperm count.
Diet and fertility: There’s no such thing as a fertility diet, but experts say these 6 foods may help.
Choosing supplements can be tricky. Try these tips for choosing safe and high-quality, over-the-counter supplements.
Very few studies track whether couples end up getting pregnant when the man is taking L-carnitine supplementation. So, it’s unclear if L-carnitine supplementation helps to increase pregnancy rates.
What it is: Like L-carnitine, coenzyme Q10 (CoQ10) is a natural antioxidant. Your body uses it in the process of converting food to energy.
What the research shows: Large reviews support that CoQ10 supplementation improves sperm motility and concentration. Smaller studies found different effects at different doses:
In one study, 400 mg daily improved sperm quality more than 200 mg daily.
Another study found improved sperm motility, sperm count, and sperm morphology after 300 mg once a day for 26 weeks. But most parameters returned to normal 30 weeks after discontinuation.
Some evidence suggests that CoQ10 may also improve pregnancy rates. But it’s not clear what the best dose should be, and in many cases, people received a combination of supplements.
What it is: Vitamin C — also known as ascorbic acid — is also a powerful antioxidant. It’s found in citrus fruits, as well as other fruits and vegetables. Vitamin C plays an important role in immune system health, as well as sperm health.
What the research shows: When it comes to vitamin C and male fertility, research is mixed. One study involved couples in fertility treatment. It found that higher vitamin C intake in men was linked to increased fertilization, but it didn’t increase pregnancy rates. A large review of studies of antioxidants (including vitamin C) found mixed results. Some studies found that vitamin C may help sperm motility, but others didn’t.
What it is: Similar to vitamin C, vitamin D supports immune system health. It’s also good for your muscles and bones.
What the research shows: Studies show a link between vitamin D and male fertility. Low levels of vitamin D have been linked to decreased sperm motility, lower levels of fertility hormones (like testosterone), and lower sperm concentration and irregular morphology. So, it makes sense to study the effects of vitamin D supplementation on fertility.
Some studies suggest that vitamin D supplementation may increase sperm motility and morphology in men with infertility. But others don’t. Large analyses have concluded that vitamin D can increase sperm motility, but it doesn’t reliably affect other sperm parameters.
What it is: Vitamin E is also a strong antioxidant, like many of the supplements we’ve covered so far. You can get vitamin E in your diet from nuts, seeds, and green vegetables.
What the research shows: Research suggests that vitamin E may have beneficial effects on sperm motility when it’s combined with other antioxidants. But, on its own, it usually doesn’t have much effect.
Vitamin E supplementation has also been studied in couples undergoing in vitro fertilization (IVF). One small, randomized trial found that the live birth rate increased when men from infertile couples took 400 mg of vitamin E once a day for 3 months. But, in another study, the same dose taken over two months made no difference in live births.
What it is: Selenium is a mineral with antioxidant properties. It plays an important role in thyroid function and the development of sperm.
What the research shows: Data suggests that selenium supplementation may boost male fertility:
Taking 200 mcg daily for 6 months improved sperm concentration and motility in infertile men.
Taking 200 mcg daily also improved sperm count and morphology in infertile men.
A meta-analysis concluded selenium might improve sperm concentration in infertile men.
There’s very little research on selenium’s effect on pregnancy rates.
What it is: Lycopene is a natural pigment that gives red and pink foods their color — think tomatoes, red bell peppers, and watermelon. And you probably already guessed that it’s a strong antioxidant.
What the research shows: Small studies support lycopene as a way to boost male fertility. Daily supplementation:
Improved sperm motility and morphology in healthy men
Increased sperm count and concentration in infertile men
A review paper also reported similar findings in infertile men who took lycopene supplementation. But the authors called out the need for larger, randomized, controlled trials for more reliable results. Lycopene’s effects on pregnancy are unknown.
What it is: N-acetyl cysteine (NAC) is a medication that treats acetaminophen overdoses and certain lung conditions. It’s also available as a supplement, since it has anti-inflammatory and antioxidant properties.
What the research shows: Several studies suggest that NAC supplementation supports male fertility. An analysis of randomized, controlled trials found an improvement in sperm concentration, motility, and morphology when infertile men took NAC daily.
Some research suggests NAC supplementation in women may improve pregnancy rates. But there’s very little data in men. In one small study, 27 of 92 couples conceived spontaneously when the man was taking 600 mg of NAC daily.
What it is: Omega-3s are fats that your body uses to build cells and produce energy. They’re found in fatty fish, and many people take omega-3 supplements to treat high triglycerides.
One omega-3, called docosahexaenoic acid (DHA), is important for functional sperm cells. Higher blood and semen levels of omega-3s are linked to better sperm motility, morphology, and total sperm count.
What the research shows: A large review paper suggested that omega-3 supplementation and a diet high in fish could be beneficial. It found an improvement in sperm motility in most, but not all, of the studies reviewed. But another review of studies suggested omega-3’s greatest potential is improving sperm concentration.
There’s very little data regarding omega-3 fatty acid supplementation and pregnancy rates.
What it is: An herb often used to decrease stress and anxiety, ashwagandha may also improve male fertility.
What the research shows: There’s less robust research on ashwagandha as a fertility supplement than the other supplements discussed in this article. Large reviews that include mostly small studies find that ashwagandha supplementation in men with low sperm count could increase sperm count and motility.
Still, as with many of the previously mentioned supplements, more research is needed to better understand how ashwagandha works and what a safe and effective dose is for male infertility.
We’ve covered a lot of different supplements! Below, we’ve summarized key takeaways.
First, most of the research here focuses only on the supplements taken alone. Taking supplements in combination may be more effective than taking them alone.
And it’s worth mentioning that the studies referenced earlier have a lot of differences. For example, there’s variation in:
The age of participants
Participants’ lifestyle factors (e.g., smoking)
Doses of supplements
How long supplements were taken
This variation makes it harder to compare the supplements and make definite conclusions, since those other factors could influence results.
Also, the American Urological Association points out that the benefits of supplements for male infertility remain unclear. The existing data isn’t sufficient enough to know which supplements to recommend.
Remember to speak to your primary care provider or pharmacist before starting any supplement. They can check for potential interactions or side effects based on your health and any medicines you take.
Supplements aren’t the only thing to consider when it comes to male fertility. Other factors may play a role, such as:
Age
Genetics
Smoking
Drinking alcohol
Recreational drug use
Diet
Body size
Stress
Some of these factors can be changed, and others can’t. But it helps to understand what plays a role in fertility. If you’re struggling with fertility, it’s a good idea to get medical attention to see if fertility testing is right for you.
There’s a growing body of research that supports supplements to enhance male fertility. But the results of a lot of the studies vary, and it’s hard to say with certainty which supplements are best. It’s also not clear if any supplements help achieve pregnancy. Antioxidants — like L-carnitine, coenzyme Q-10, and omega-3s — have been shown to improve the greatest number of sperm qualities, like sperm count, motility, and morphology. Additional studies are needed to understand if antioxidants affect live birth rates.
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