Approximately 15% of couples are unintentionally childless. For close to 60% of these couples, the cause of childlessness rests with the limited fertility of the male partner.
The quality of sperm has been decreasing over the last several decades, a clear yet daunting trend 1. On average, a typical 30 year-old male today has less than half the sperm capable of fertilizing an egg than his counterpart 50 years ago. Most researchers contribute this to a generally poor diet 2.
A long-term French study conducted in 2012 found that the average sperm quality (count, concentration, motility) in men has declined 33% in just the last 17 years.
The study included spermiograms from more than 5,000 men at various clinics. The results can therefore be deemed highly significant.
It is estimated that 40% of men worldwide evidence a bad spermiogram and subsequently have only limited fertility.
- 1 Causes of limited fertility
- 2 Normal spermiogram according to WHO parameters
- 3 Amino acids that improve the spermiogram
- 4 Pine Bark Extract
- 5 Vitamins and Trace Elements
- 6 Vitamin D Deficiency: 85% affected
- 7 Which amino acids are the best for increasing male fertility?
- 8 Which products offer good value for money?
- 9 A regimen of at least 3 months is necessary
- 10 Vitamin and amino acid therapy without side effects
- 11 Which products promote sperm development?
- 12 Other actions you can take to promote healthy sperm
- 13 Bibliography
Causes of limited fertility
While specific causes have not yet been identified, researchers agree that the likely culprit is a combination of increasing environmental pollution and poor diet.
During the last 25 years, independent universities have conducted over 200 studies on human beings. These studies have shown that various amino acids, vitamins, and trace elements play a key role in sperm quality.
These micro nutrients, i.e., vitamins, amino acids and trace elements, as well as plant extracts are available as diet supplements. As these products are mostly well tolerated and have been found to be generally harmless, they do not require a prescription.
However, that does not mean amino acids and vitamins are not potent. In fact, an analysis of 17 selected clinical studies evidences that they are highly effective. In 82% of the studies, sperm quality was improved, and in 60%, significantly higher pregnancy rates were observed 3.
Normal spermiogram according to WHO parameters
A normal semen analysis, as defined by WHO (World Health Organization), has the following characteristics 4
|Indicator||Benchmark value (WHO 2010)||Benchmark value (WHO 1999)|
|Ejaculate Volume||above 1.5 ml||above 2.0 ml|
|Sperm Count (million / ml)||above 15||above 20|
|Total Sperm||above 39 million||above 40 million|
|pH Value||above 7.2||above 7.2|
|% Normal Forms (Morphology)||more than 4% normal forms||more than 14% normal forms|
|Progressive Movement (Motility)||more than 32% progressive||more than 50% progressive|
|Total Motility||more than 40%||more than 50%|
|Vitality in %||more than 50%||more than 50%|
|Antibodies||Less than 50% with antibodies||Less than 50% with antibodies|
|White Blood Cells (million / ml)||below 1||below 1|
As you will note, WHO has eased some of the criteria for 2010 when compared to the standards of 1999. Men who were considered to be of limited fertility according to the older WHO definitions, fall into the fertile category with today’s standards.
When the results are borderline, many doctors recommend that men conscientiously support sperm development through proper diet and healthy habits. Combinations of amino acids and vitamins are recommended even when a childless couple decides to try artificial insemination or in-vitro fertilization (IVF), as these can increase the likelihood of successful fertilization.
Amino acids that improve the spermiogram
L-arginine: building block of spermine and spermidine
The greatest components of male ejaculate, spermine and spermidine, contain L-arginine. For this reason, tests to determine if taking L-arginine would have a positive effect on the quality of spermiograms of men with limited fertility were conducted early on.
And yes indeed: one study showed that by taking a daily dose of 4,000 mg L-arginine, 75% of the men with insufficiently motile sperm were able to significantly improve their spermiograms 5.
In a follow-up study conducted in Italy, men with normal sperm concentration (more than 20 million per ml), but limited sperm motility, received L-arginine. The daily dosage of 8,000 mg was very high. Results of this study also indicate a significant improvement in sperm motility 6.
L-carnitine: necessary to power cells
With a L-carnitine concentration of 2,000 times that of blood, spermatozoa are the cells with the most carnitine in the body. L-carnitine transports fatty acids into the cell interior, where they are used to generate energy.
Energy generation is of particular importance to sperm, and much of their energy comes from fatty acids. Relative to their size, sperm have to travel a great distance to reach the ovum.
Even in a man of normal fertility, approximately only half of his sperm is sufficiently motile. A proportion of normally motile sperm in the ejaculate less than a certain percentage (according to WHO, at least 32% progressively motile, see above) results in a condition called “asthenozoospermia”.
Studies have shown that men with asthenozoospermia could significantly improve the motility of existing sperm by taking L-carnitine. In a study in which men received a daily dose of 3,000 mg l-carnitine, the proportion of motile sperm was improved by 75% (from 10.8% to 18.0%) 7.
An Italian study, conducted following the highest clinical standards, demonstrated that taking L-carnitine over a period of six months significantly improved sperm motility 8. These findings were later confirmed in a subsequent study 9.
L-cysteine and Glutathione
Glutathione is a tripeptide, a compound of three amino acids. It is one of the best protectors against free radicals and other oxidative stress. A sufficient supply of the amino acid, cysteine, is of particular importance to the body’s production of glutathione.
Several studies point to a correlation between sufficient blood levels of glutathione and improved fertility. Preferably, cysteine should be taken in the form of the stable N-acetyl cysteine (NAC) to improve glutathione levels.
Pine Bark Extract
Pine Bark Extract contains a high amount of proanthocyanidins. These polyphenols have anti-inflammatory, anti-bacterial qualities that protect blood vessels, and can also help protect sensitive sperm.
Several clinical studies have shown that sperm count and quantity can be significantly increased by taking L-arginine in combination with Pine Bark Extract 10.
The combination of Pine Bark Extract and L-arginine also has a welcome side effect for couples: the male partner may experience increased potency due to improved blood circulation. This was observed in multiple instances.
Vitamins and Trace Elements
Vitamins and trace elements are of similar importance in the creation and protection of sperm capable of fertilization. They play a role in generation, as well as in protection against oxidative stress (free radicals).
Vitamin C (ascorbic acid) is the most important water-soluble vitamin with anti-oxidative functions. Vitamin C levels in semen are directly related to the amount of vitamin C consumed in the diet.
There is a correlation between low vitamin C levels and reduced fertility, as well as an increase in genetically damaged sperm 11.
Various studies have concluded that a daily dose of just 200 mg of vitamin C can result in significant improvements in sperm count 12, 13. Increasing the dosage (1,000 mg to 2,000 mg) brings slightly better results.
It is very surprising that despite the broad availability of fresh fruits and vegetables and the consumption of dietary supplements, approximately one third of the population do not receive the recommended minimum daily dose of vitamin C (at least 80 mg a day). Vitamin C deficiency was brought to light by the federal government’s ministry of agriculture and consumer protection (Bundesministerium für Landwirtschaft und Verbraucherschutz) 14.
Vitamin E is the most important fat-soluble antioxidant and protects fats from oxidative stress. Therefore, a small amount of Vitamin E is added to high-quality oils with omega-3 fatty acids during production.
Several studies have shown that taking a high dose of vitamin E in combination with selenium and other antioxidants can improve the number and concentration of motile sperm, as well as the quantity of sperm 15, 16.
In one study, 32% of the couples who received the vitamin E and selenium supplements conceived. In the control group, which received a placebo, only 3% of the couples became pregnant.
Vitamin D (often referred to as the sun vitamin because the body can produce it when exposed to UV light) is in many parts of the western world the No. 1 deficient vitamin. The cause: lack of exposure to sunlight. Even if one dares to sit in the sun over lunch, sunscreen is applied to the skin.
Many cosmetic products also contain UV protection. While these measures reduce the risk of skin cancer and the development of wrinkles, the skin can no longer produce the necessary amounts of vitamin D.
In addition to a weakened immune system, fatigue, and problems with calcium absorption (long term, these can lead to osteoporosis), limited fertility in men is also related to a deficiency in vitamin D 17.
Researchers surmise that vitamin D deficiency not only has a negative impact on sperm generation, but also has an adverse effect on the fertilization process.
Approximately 80% of the population do not get enough folic acid, vitamin B9. Folic acid is important for cell division and cellular energy supply.
It is widely known that a deficiency of folic acid in women during the first weeks of pregnancy results in a fourfold increase in the risk of birth defects, specifically spina bifida.
For men, low folic acid levels are associated with an increase in the number of genetically damaged sperm 18. In several studies, supplementation with folic acid resulted in improved sperm motility 19.
Zinc is a trace element that is involved in the creation of more than 200 enzymes. It is also vital for male fertility and plays a role in the body’s production of the male hormone, testosterone.
Various studies saw significantly positive effects of zinc on sperm genesis. Men with a sperm count of less than 8 million sperm per ml (normal sperm count is at least 20 million per ml) and low testosterone were given a dose of 24 mg zinc daily.
After three months of zinc therapy, the men reached a sperm count of 20 million per ml. They had thus attained normal sperm concentration according to WHO standards.
Testosterone levels increased markedly as well, and thereby the fundamental sex drive. The ultimate result was nine pregnancies 20.
Which amino acids are the best for increasing male fertility?
Many earlier studies involved very high dosages of single amino acids and other micro nutrients. These high doses, however, were only available through a prescription in many countries.
More recent studies have concluded that the best results can be achieved with a combination of the most important components in a moderately high dose that is easier to digest. This makes sense, since a chain is only as strong as its weakest link.
L-arginine, L-carnitine, glutathione, vitamin E, vitamin C, folic acid, Q10, selenium, and zinc are highly effective on their own, but achieve positive results particularly when used in combination with one another.
This was confirmed by three studies. Following a three month regimen of a combination therapy, 25% of the men who participated in the first study again attained a normal spermiogram 21.
In a second study, the results of combination therapy were compared to the results of a control group that received a placebo. The group receiving the combination therapy showed significant increases in sperm concentration and motility. The group receiving the combination therapy had 34 pregnancies, while the group receiving the placebo saw only 11 22.
A Brazilian study using a similar combination of vitamins, amino acid, and trace elements confirmed that spermiograms can be significantly improved with this approach 23.
A regimen of at least 3 months is necessary
Spermatogenesis occurs in the seminiferous tubules of the testes. Approximately 1,000 sperm are produced every second, up to 4 million in one hour.
One ml of semen contains 20 to 64 million spermatozoa. If a man evidences a sperm count of less than 20 million per ml, his condition is referred to as oligozoospermia, and his fertility is limited.
Sperm need two to three months to fully mature. During this time, these sensitive cells need to be protected from oxidative stress and supplied with the proper nutrients. Studies that measured the effects of amino acids and vitamins on sperm development were therefore conducted over a period of at least three to nine months.
Since amino acids, vitamins, and trace elements are naturally-occurring, specialized nutritional compounds, adding them to one’s diet generally does not cause any adverse side effects. In many cases, just the opposite is true: amino acids, vitamins, and trace elements are micro nutrients that may provide additional health benefits.
For example, they may strengthen the immune system, or have positive effects on circulation and the regeneration of skin. Therefore, there is generally no medical reason not to continue amino acid or vitamin therapy for a period of six or even twelve months.
Other actions you can take to promote healthy sperm
Various habits can also help in promoting healthy development of sperm:
- Avoid smoking and alcohol: both damage sperm and are associated with limited fertility and reduced likelihood of pregnancy.
- Avoid medications: several drugs are suspected of reducing fertility. Only take drugs when necessary and prescribed by your physician.
- Avoid heat: sperm development in the testes is sensitive to heat. Heated seats in a car or tight-fitting pants should therefore be avoided.
- Lose weight: Men of normal weight (i.e., with a BMI (Body Mass Index) of 20 to 25) have significantly more and healthier sperm than their overweight counterparts. Reduce your intake of unhealthy foods, without sacrificing necessary vitamins and trace elements. Get regular exercise, preferably outdoors. This may improve your mood and vitamin D level.
- Fruits and vegetables, (particularly raw fruits and vegetables): consume raw food, vegetables and fruits in large quantities. Be sure to wash fruits and vegetables thoroughly. Organic products are preferred as they contain fewer pesticides and other harmful substances.
- Swan SH, Elkin EP, Fenster L. The question of declining sperm density revisited: An analysis of 101 studies published 1934-1996. Environmental Health Perspectives. 2000. 108 (10):961-966 ↩
- Sinclair S. Male Infertility: Nutritional and Environmental Considerations. Alternative Medicine Review. 2000. 5(1):28-38 ↩
- Ross C, Morriss A, Khairy M, Khalaf Y, Braude P, Coomarasamy A, El-Toukhy T. A systematic review of the effect of oral antioxidants on male infertility. Reproductive BioMedicine Online. 2010. 20(6):711-723 ↩
- World Health Organization. Laboratory manual for the examination of human semen and sperm–cervical mucus interaction. WHO 5th ed. WHO. 2010. ↩
- Schachter A, Goldman JA, Zukerman Z. Treatment of oligospermia with the amino acid arginine. Journal of Urology. 1973. 110(3):311-313 ↩
- Scibona M, Meschini P, Capparelli S, Pecori C, Rossi P, Menchini Fabris GF. L-arginine and male infertility. Italian Journal of Urology and Nephrology. 1994. 46(4):251-253 ↩
- Costa M, Canale D, Filicori M, D’Iddio S, Lenzi A. L-carnitine in idiopathic asthenozoospermia: a multicenter study. Andrologia. 1994. 26(3):155-159 ↩
- Lenzi A, Lombardo F, Sgro P, Salacone P, Caponecchia L, Dondero F, Gandini L. Use of carnitine therapy in selected cases of male factor infertility: a double-blind crossover trial. Fertility and Sterility. 2003. 79(2):292-300 ↩
- Balercia G, Regoli F, Armeni T, Koverech A, Mantero F, Boscaro M. Placebo-controlled double-blind randomized trial on the use of L-carnitine, L-acetylcarnitine, or combined L-carnitine and L-acetylcarnitine in men with idiopathic asthenozoospermia. Fertility and Sterility. 2005. 84(3):662-671 ↩
- Roseff SJ. Improvement in sperm quality and function with French maritime pine tree bark extract. Journal of Reproductive Medicine. 2002. 47(10):821-4 ↩
- Dabrowski K, Ciereszko A. Ascorbic acid protects against male infertility in a teleost fish. Cellular and Molecular Life Sciences. 1996. 52(2):97-100 ↩
- Fraga CG, Motchnik PA, Shigenaga MK, Helbock HJ, Jacob RA, Ames BN. Ascorbic acid protects against endogenous oxidative DNA damage in human sperm. Proceedings of the National Academy of Sciences of the United States of America. 1991. 88(24):11003-11006 ↩
- Dawson EB, Harris WA, Rankin WE, Charpentier LA, McGanity WJ. Effect of ascorbic acid on male fertility. Annals of the New York Academy of Sciences. 1987. 498:312-323 ↩
- National Consumption Report. Report of Findings – Part 2. Attachment- Vitamin C. 2008 ↩
- Moslemi MK, Tavanbakhsh S. Selenium-vitamin E supplementation in infertile men: effects on semen parameters and pregnancy rate. International Journal of General Medicine. 2011. 4:99-104 ↩
- Keskes-Ammar L, Feki-Chakroun N, Rebai T, Sahnoun Z, Ghozzi H, Hammami S, Zghal K, Fki H, Damak J, Bahloul A. Sperm oxidative stress and the effect of an oral vitamin E and selenium supplement on semen quality in infertile men. Archives of Andrology. 2003. 49(2):83-94 ↩
- Hammoud AO, Meikle AW, Peterson CM, Stanford J, Gibson M, Carrell DT. Association of 25-hydroxy-vitamin D levels with semen and hormonal parameters. Asian Journal of Andrology. 2012. 14(6):855-9 ↩
- Boxmeer JC, Smit M, Utomo E, Romijn JC, Eijkemans MJC, Lindemans J, Laven JSE, Macklon NS, Steegers EAP, Steegers-Theunissen RPM. Low folate in seminal plasma is associated with increased sperm DNA damage. Fertility and Sterility. 2009. 92(2):548-556 ↩
- Wong WY, Merkus HMWM, Thomas CMG, Menkveld R, Zielhuis GA, Steegers-Theunissen RPM. Effects of folic acid and zinc sulfate on male factor subfertility: a double-blind, randomized, placebo-controlled trial. Fertility and Sterility. 2002. 77(3):491-8 ↩
- Netter A, Hartoma R, Nahoul K. Effect of zinc administration on plasma testosterone, dihydrotestosterone, and sperm count. Archives of Andrology. 1981. 7(1):69-73 ↩
- Imhof M. The use of the nutraceutical PROfertil ® a therapy of the male factors for the improvement of semen quality. EAU Bratislava. 2010 ↩
- Imhof M, Lackner J, Lipovac M, Chedraui P, Riedl C. Improvement of sperm quality after micronutrient supplementation. e-SPEN Journal. 2012. 7(1):50-53 ↩
- Ajayi R, Okhowat J, Spitzer D, Schechinger B, Zech N. Impact of antioxidative supplementation on semen quality according to MSOME criteria. JBRA Assisted Reproduction. 2013. 17(1) ↩