There are many steps men can take to maintain and preserve their fertility. From living healthy lifestyles to quitting smoking — your fertility is a matter of several factors working together. We encourage everyone to talk to their doctor about making the right changes that work for your body and family. One nutrient that men should ensure that they are getting the right amount of are amino acids.
There are some amino acids that are produced naturally within the body while others are only able to reach healthy levels when we consume them from food or via supplementation. One of the most important amino acids in relation to fertility is L-carnitine. The body is able to produce L-carnitine on its own, but data from a study of 20 couples shows that supplementing your diet with certain forms of this incredible compound can help support male fertility levels.1
What are amino acids?
Amino acids2 are organic compounds, which are quite literally the building blocks of life. When they combine they form proteins. When you digest amino acids they help the body break down food, repair tissue, promote growth, and other benefits. Our body is made up of countless amino acids that we rely on for everything from performing everyday tasks to building muscle and staying healthy. Amino acids are also a great source of energy.
Nonessential amino acids are capable of being produced within the body, while essential amino acids can only be obtained from our diet or via supplementation.
Of the essential amino acids, the most famous one is probably tryptophan3, which is beneficial for growth, healthy sleep, and balanced mood. Two essential amino acids, L-Lysine and LMethionine are particularly interesting as they combine to create L-carnitine.4
What does L-Carnitine do for you?
L-carnitine is produced naturally in the body when L-lysine and L-methionine are able to bind with one another. Once created, it helps support heart and brain health, while also having proven benefits for athletes via increased energy production. However, the energy L-carnitine provides the body isn’t limited to our muscles. There is significant evidence that it also helps power fertility by supporting sperm production as well as sperm motility. There are some treatments that require L-carnitine to be administered intravenously, but most can be taken by mouth.5
What foods are high in amino acids?
In addition to supplements, men can also increase the amount of amino acids in their bodies by being more conscious about the foods they eat.6 For example, lysine is an essential amino acid that helps with building muscle and bone strength. It’s found in meat, eggs, soy, and pumpkin seeds. Histidine —found in meat, fish, nuts, and whole grains — facilitates tissue repair and growth. Isoleucine helps with wound healing and hormone production and can be added to the diet in cheese and lentils. In addition to supplements, carnitine is also found in red meat, dairy products, beans, and avocado.
Sources of Carnitine7:
- 4 ounces of cooked beef: 56-162 milligrams
- 4 ounces of cooked ground beef: 87-99 milligrams
- 1 cup of whole milk: 8 milligrams
- 4 ounces of cooked codfish: 4-7 milligrams
- 4 ounces of cooked chicken breast: 3-5 milligrams
- 2 ounces of cheddar cheese: 2 milligrams
1 Mongioi, L., A. E. Calogero, E. Vicari, R. A. Condorelli, G. I. Russo, S. Privitera, G. Morgia, and S. La Vignera. “The Role of Carnitine in Male Infertility – Mongioi – 2016 – Andrology – Wiley Online Library.” Andrology. John Wiley & Sons, Ltd (10.1111), May 6, 2016. https://onlinelibrary.wiley.com/doi/full/10.1111/andr.12191.
2 Wax, Emily. “Amino Acids: MedlinePlus Medical Encyclopedia.” MedlinePlus. February 2, 2019. Accessed July 10, 2019. https://medlineplus.gov/ency/article/002222.htm.
3 Wax, Emily. “Tryptophan: MedlinePlus Medical Encyclopedia.” MedlinePlus. January 13, 2018. Accessed July 10, 2019. https://medlineplus.gov/ency/article/002332.htm.
4 Pekala, Jolanta, et al. “L-Carnitine–Metabolic Functions and Meaning in Humans Life.” Current Drug Metabolism, U.S. National Library of Medicine, Sept. 2011, https://www.ncbi.nlm.nih.gov/pubmed/21561431.
5 “L-Carnitine: Uses, Side Effects, Interactions, Dosage, and Warning.” WebMD. Accessed July 10, 2019. https://www.webmd.com/vitamins/ai/ingredientmono-1026/l-carnitine.
6 Berry, Jennifer. “Essential Amino Acids: Definition, Benefits, and Foods.” Medical News Today. January 21, 2019. Accessed July 10, 2019. https://www.medicalnewstoday.com/articles/324229.php.
7 “Office of Dietary Supplements – Carnitine.” NIH Office of Dietary Supplements. October 10, 2017. Accessed July 30, 2019. https://ods.od.nih.gov/factsheets/Carnitine-HealthProfessional/.