Infertility is a growing problem worldwide.
It affects about one in every six couples, and researchers estimate about one in every three cases is due to fertility problems in the male partner alone (1, 2).
While infertility is not always treatable, it can sometimes be improved with a healthy diet, supplements and other lifestyle strategies.
This article lists some of the main lifestyle factors, foods, nutrients and supplements that have been associated with improved fertility in men.
What Is Male Infertility?
Fertility refers to people's ability to reproduce by natural means.
Male infertility is when a man has a poor chance of making his female partner pregnant. It usually depends on the quality of his sperm cells.
The following aspects of sexual function and semen quality may affect fertility:
Libido: Otherwise known as sex drive, libido describes a person's desire to have sex. Foods or supplements that claim to increase libido are called aphrodisiacs.
Erectile dysfunction: Also known as impotence, erectile dysfunction is when a man is unable to develop or maintain an erection.
Sperm count: An important aspect of semen quality is the number or concentration of sperm cells in a given amount of semen.
Sperm motility: An essential function of healthy sperm cells is their ability to swim. Sperm motility is measured as the percentage of moving sperm cells in a sample of semen.
Testosterone levels: Low levels of testosterone, the male sex hormone, may be responsible for infertility in some men.
Infertility can have multiple causes and may depend on genetics, general health, fitness, diseases and dietary contaminants.
Additionally, a healthy lifestyle and diet are important. Some foods and nutrients are associated with greater fertility benefits than others.
Here are 10 science-backed ways to boost sperm count and increase fertility in men.
- Take D-Aspartic Acid Supplements
D-aspartic acid (D-AA) is a form of aspartic acid, a type of amino acid that's sold as a dietary supplement.
It should not be confused with L-aspartic acid, which makes up the structure of many proteins and is far more common than D-AA.
D-AA is mainly present in certain glands, such as the testicles, as well as in semen and sperm cells.
Researchers believe that D-AA is implicated in male fertility. In fact, D-AA levels are significantly lower in infertile men than fertile men (3).
This is supported by studies showing that D-AA supplements may increase levels of testosterone, the male sex hormone that plays an essential role in male fertility.
For instance, an observational study in infertile men suggested that taking 2.66 grams of D-AA for three months increased their testosterone levels by 30–60% and sperm count and motility by 60–100%.
The number of pregnancies also increased among their partners (4).
Additionally, a controlled study in healthy men showed that taking 3 grams of D-AA supplements daily for two weeks increased testosterone levels by 42% (5).
If you are interested in trying a d-aspartic acid supplement, there is a good selection available on Amazon.
However, the evidence is not entirely consistent. Studies in athletes or strength-trained men with normal to high testosterone levels found that D-AA didn't increase its levels further and even reduced them at high doses (6, 7).
Taken together, the current evidence indicates that D-AA supplements may improve fertility in men with low testosterone levels, while they don't consistently provide additional benefits in men with normal to high levels.
Further studies need to investigate the potential long-term risks and benefits of D-AA supplements in humans.
- Exercise Regularly
Exercising not only improves your confidence and physical performance — it may also raise your testosterone levels.
Studies show that men who exercise regularly have higher testosterone levels and better semen quality than men who are inactive (8, 9, 10).
However, you should avoid too much exercise, as it may have the opposite effect and potentially reduce testosterone levels. Adequate zinc intake can minimize this risk (11, 12, 13).
If you rarely exercise but want to improve your fertility, becoming more physically active should be one of your top priorities.
- Get Enough Vitamin C
Oxidative stress is when levels of reactive oxygen species (ROS) reach harmful levels in the body.
It happens when the body's own antioxidant defenses are overwhelmed because of disease, old age, an unhealthy lifestyle or environmental pollutants (14, 15, 16).
ROS are constantly being produced in the body, but their levels are kept in check in healthy people. High levels of ROS may promote tissue injury and inflammation, increasing the risk of chronic disease (17).
There is also some evidence that oxidative stress and excessively high levels of ROS may lead to infertility in men (18, 19).
Adequate intake of antioxidants, such as vitamin C, may help counteract some of these harmful effects. There is also some evidence that vitamin C supplements may improve semen quality.
A study in infertile men showed that taking 1,000-mg vitamin C supplements twice a day for up to two months increased sperm motility by 92% and sperm count by more than 100%. It also reduced the proportion of deformed sperm cells by 55% (20).
Another observational study in Indian industrial workers suggested that taking 1,000 mg of vitamin C five times a week for three months may protect against DNA damage caused by ROS in sperm cells.
Vitamin C supplements also significantly improved sperm count and motility, while reducing the numbers of deformed sperm cells (21).
Taken together, these findings suggest that vitamin C may help improve fertility in infertile men suffering from oxidative stress.
However, controlled studies are needed before any definite claims can be made.
- Relax and Minimize Stress
Stress may reduce your sexual satisfaction and impair your fertility (22, 23, 24).
Researchers believe the hormone cortisol may partly explain these adverse effects of stress.
Prolonged stress raises levels of cortisol, which has strong negative effects on testosterone. When cortisol goes up, testosterone levels tend to go down (25, 26).
While severe, unexplained anxiety is typically treated with medication, milder forms of stress can be alleviated by numerous relaxation techniques.
Stress management can be as simple as taking a walk in nature, meditating, exercising or spending time with friends.
Try Tribulus Terrestris
Tribulus terrestris, also known as puncturevine, is a medicinal herb frequently used to enhance male fertility.
One study in men with low sperm counts showed that taking 6 grams of tribulus root daily for two months improved erectile function and libido (31).
While Tribulus terrestris does not raise testosterone levels, research indicates that it may possibly enhance the libido-promoting effects of testosterone (32, 33, 34).
However, further studies need to confirm its aphrodisiac properties and evaluate the long-term risks and benefits of supplementing with it.