Can a Man Boost His Fertility Through Diet?

Among men's health issues, infertility may not be top of mind. Yet it has become a major health issue in recent decades for women and men alike. In the United States alone, about 4 million men seek help for fertility issues every year.¹

Some of the suspected causes of male infertility include stress, air pollution, and other environmental toxins. Researchers also suspect that diet can play a role, by affecting sperm concentration and quality, as well as the basic functioning of the reproductive system.¹

Eating a healthy diet is consistently related to better semen quality, a fact observed in men from many backgrounds. And unhealthy diets are connected to poor semen quality.² Although there is no official "fertility diet," a few general rules can help ensure your diet is helping, rather than hampering, your co-effort to make a baby.

Here's your guide to food and fertility for men. 

Choose these foods

1. Vegetables and fruits

If you're aiming for strong sperm, then don't pass on the broccoli. A diet abundant in fruits and vegetables is connected to better semen quality.² Fruits and vegetables are rich in antioxidants, like vitamin C, vitamin E, and beta carotene – antioxidants that protect the body against specific molecules (reactive oxygen species or free radicals) that damage cells. Free radicals can affect sperm motility – their ability to move – as well as their ability to attach to eggs.^3,4

Research also suggests that folate – a B vitamin common in fruits and vegetables (especially leafy greens) – is essential for the creation of sperm.⁴

2. Fish and seafood

Fish and shellfish contain high levels of omega-3 polyunsaturated fatty acids (PUFAs). Researchers have observed a strong link between these essential fatty acids and sperm motility and concentrations.

One randomized, controlled trial involved men with a specific kind of infertility and low levels of fatty acids. Supplementing their diet with omega-3 PUFAs improved several aspects of semen quality, including higher sperm counts.^1,5

A word of caution, however. Some research indicates that pollutants in fish, especially fatty fish, can impair sperm quality.⁶ So consider acquiring your omega-3s from a fish oil supplement that has been tested for PCBs, heavy metals, and other contaminants.

Be wary of these foods

Although the foods in the following list don't necessarily cause infertility, evidence indicates they might affect sperm quality and other aspects of reproduction.

1. Saturated and trans fats

Saturated fatty acids and trans-fatty acids are both connected to lower sperm quality. For instance, one study showed that infertile men had higher levels of saturated fatty acids in their sperm. In animal models, high levels of trans-fatty acids stopped the production of sperm altogether.^1-3

Studies have also linked these fats to decreased testicular function, such as lower sperm volume and lower levels of testosterone.²

2. Meat

Certain types of meat, in particular, processed meats like bacon, bologna, salami, jerky, etc., have been shown to lower semen quality.³ Meat can also contain estrogens not produced by the human body, as well as anabolic steroids.

One randomized, controlled human study showed that these compounds harm semen quality.¹ Hormones, pesticides, and other potential contaminants can be avoided or significantly reduced by choosing organic beef, chicken, and other meats.

3. Potatoes and other high-starch foods

High-starch foods like potatoes have a high glycemic index, which means they increase blood sugar levels. Higher blood sugar levels are associated with oxidative stress, meaning your body creates free radicals that damages cells, which studies have shown reduces semen quality.^1,2 

4. Sweets

For the same reason starchy foods should be limited, sugary sweets should also be eaten in moderation, if at all. High sugar in the bloodstream can disrupt the endocrine glands that are responsible for sperm production.

Also, sweets and sweetened drinks can contain contaminants that have leached from their containers, which can impact sperm quality.¹

5. Caffeine

In general, the impact of caffeine on fertility is not well known.⁷ Some researchers believe too much caffeine can increase testosterone levels, which could upset the endocrine system and impact sperm production.¹

Others have found that coffee drinking might impair sperm quality.⁸ And one study showed that drinking three or more cups of coffee daily was connected to a lower probability of a partner's pregnancy.⁹

The jury is still out on these foods

The evidence on whether the following foods affect male fertility is contradictory or uncertain.

1. Alcohol

The evidence of alcohol's effect on fertility is contradictory, with some studies showing a negative effect and others showing no effect or even a positive one.^1,10 Most researchers suggest that moderate alcohol use does not play a role in male infertility.^2,9

Heavy use of alcohol is a different story – it's connected to abnormal testicular function, including lower sperm production.^7,9

2. Dairy

Studies show that full-fat dairy products can impair sperm quality. One reason might be that dairy contains naturally-occurring estrogens from the cow, and estrogens can decrease sperm production. Because estrogens are fat soluble, they are found in higher amounts in full-fat dairy products that in low-fat dairy products.

In fact, researchers have linked low-fat dairy to better sperm concentrations and motility.^1,3

If you are going to eat full-fat dairy products, it’s best to choose organic. A study from the University of Washington found milk from organic dairies has a much higher amount of the beneficial omega-3 fatty acids when compared to milk from conventional dairies.

Foraging on grasses resulted in even higher amounts of omega-3s compared to omega-6 fatty acids.¹⁰ 

3. Soy

The effect of soy on male fertility is far from proven. Some researchers believe that because soy-based foods contain plant estrogens (also known as phytoestrogens), which are known to negatively impact the male hormonal system, they might affect fertility.

Some human studies and animal models bear this out.^3,11,12 But the only randomized, controlled human study designed to test this hypothesis showed that soy had no effect on fertility.¹

Do supplements help?

It’s not always east to get all the essential nutrients from diet alone. In these instances, supplements are likely helpful. The benefits from supplements in men who have well-balanced diets aren't as clear. The following dietary supplements have been studied for their effects on male fertility.

• Fish oil (omega-3 PUFAs) – Researchers have made a strong link between omega-3 PUFAs and improved sperm quality.*¹ The omega-3 fatty acid DHA is found in high concentrations in the heads of healthy human sperm.*¹³ Studies of men who took supplements containing the omega-3 fatty acids DHA and EPA showed improvements in the number and quality of sperm.*¹⁴
• Vitamin E – Vitamin E is an antioxidant that might help improve sperm motility.*⁵ Studies of men undergoing infertility treatment show that taking antioxidant supplements can increase the chance of pregnancy.*¹⁴
• Vitamin C – Like vitamin E, vitamin C is also an antioxidant. In one study of infertile men, vitamin C supplementation increased sperm counts up to 140 percent.*^9,15
• Selenium – Selenium's effect on sperm quality has mixed results. Two randomized, controlled trials failed to show any positive effect. But it did increase motility when taken with vitamin A in men who had low selenium levels.^3,6
• Zinc – The concentration of zinc in the male reproductive tract, including the testes, is high. Studies have shown that zinc supplements can increase the number of sperm in men with certain kinds of infertility.* One study suggested that zinc needs to be used in conjunction with folate.^5,6
• Other antioxidants – Some evidence shows a connection between sperm count and other antioxidants, like beta-carotene, cryptoxanthin, lycopene, vitamin D, and folate. While some, such as beta-carotene, show slight improvements on their own, they seem to be more effective when they are taken in combination. For instance, beta-carotene shows higher efficacy when taken with vitamin C and lycopene.^1,11
• Coenzyme Q10 – Coenzyme Q10 (CoQ10) is also an antioxidant. There's a direct correlation between levels of CoQ10 in seminal fluid and sperm health.¹¹ Several studies have found that in men with lower fertility, CoQ10 supplements can increase sperm motility, concentrations, and overall counts.*^5,16
• L-carnitine/acetyl-L-carnitine – Carnitine is a compound found in the male genital tract and in sperm. Evidence suggests that low carnitine levels contribute to some sperm disorders.*¹⁴

Looking beyond diet

Eating a healthy diet is just one aspect of a healthy lifestyle. If you are preparing for the possibility of a baby, then you should also look at your other habits. Maintaining a healthy weight, exercising, and not smoking can all support overall good health.^7,11 

References

1. Salas-Huetos A, Bulló M, Salas-Salvadó, J. Dietary patterns, foods and nutrients in male fertility parameters and fecundability: A systematic review of observational studies. Hum Reprod Update 2017;23:371-389.
2. Gaskins A, Chavarro J. Diet and fertility: A review. Am J Obstet Gynecol 2018;4:379-389.
3. Giahi L, Mohammadmoradi S, Javidan A, Sadeghi M. Nutritional modifications in male infertility: A systematic review covering two decades. Nutr Rev 2015;74: 118-130.
4. Chiu Y, Gaskins A, Williams P, et al. Intake of fruits and vegetables with low- to-moderate pesticide residues is positively associated with semen-quality parameters among young healthy men. J Nutr 2016;146:1084-1092.
5. Yao D, Mills J. Male infertility: Lifestyle factors and holistic, complementary, and alternative therapies. Asian J Androl 2016;18:410-418.
6. Gabrielsen J, Tanrikut C. Chronic exposures and male fertility: The impacts of environment, diet, and drug use on spermatogenesis. Andrology 2016;4:648-661.
7. Hornstein M, Gibbons W, Schenken R. Optimizing natural fertility in couples planning pregnancy. https://www.uptodate.com/contents/optimizing-natural-fertility-in-couples-planning-pregnancy [Accessed 2.26.19]
8. Braga D, Halpern G, Cassia R, et al. Food intake and social habits in male patients and its relationship to intracytoplasmic sperm injection outcomes. Fertil Steril 2012;97:53-59.
9. Karmon A, Toth T, Chiu Y, et al. Male caffeine and alcohol intake in relation to semen parameters and in vitro fertilization outcomes among fertility patients. Andrology 2017;5: 354-361.
10. Benbrook CM, David DR, Heins BJ. Enhancing the fatty acid profile of milk through forage-based rations, with nutrition modeling of diet outcomes. Food Sci Nutr 2018;6(3):681-700.
11. Collins G, Rossi B. The impact of lifestyle modifications, diet, and vitamin supplementation on natural fertility. Fertil Res Pract 2015;1: 1-10.
12. Mendiola J, Torres-Cantero A, Moreno-Grau J, et al. Food intake and its relationship with semen quality: A case-control study. Fertil Steril 2009;91: 812-818.
13. Esmaeili V, Shahverdi A, Moghadasian M, Alizadeh A. Dietary fatty acids affect semen quality: A review. Andrology 2015;3:450-461.
14. Nassan F, Chavarro J, Tanrikut C. Diet and men's fertility: Does diet affect sperm quality? Fertil Steril 2018;110:570-577.
15. Adewoyin M, Ibrahim M, Roszaman R, et al. Male infertility: The effect of natural antioxidants and phytocompounds on seminal oxidative stress. Diseases 2017;5: 1-26.
16. Tiseo B, Gaskins A, Hauser R, et al. Coenzyme Q10 intake from foods and semen parameters in a subfertile population. Urology 2017;102:100-105.