Carnitine improves male fertility by supporting sperm count, sperm concentration, motility, nuclear DNA integrity and morphology.
L-Carnitine is present in almost every cell in the body. It is derived from the amino acids lysine and methionine. Carnitine is the generic name for several compounds. These include L-carnitine, acetyl-L-carnitine, and propionyl-L-carnitine. Involved in energy production, this compound delivers long-chain fatty acids to mitochondria. It helps with energy production and removes associated waste products. This amino acid also has important antioxidant properties. It can help to protect sperm cells from oxidative stress.
Red meat is very rich in L-carnitine
Clinical Study: Do low L-carnitine levels reduce male fertility?
In a study of semen samples collected from 101 men, researchers confirmed the presence of L-carnitine in seminal plasma can vary between fertile and infertile men1.
Other research conducted in Fatemieh Hospital in Hamadan, Iran confirmed low levels of L-carnitine are associated with infertile men2. In this case study, 72 infertile men and 80 fertile men had their L-carnitine levels assessed using a UV enzymatic test.
These studies found that
- Infertile men had statistically significant lower concentrations of L-carnitine compared with the fertile control group.
- Low L-carnitine levels (mean value of 100.58) were associated with an abnormal sperm parameters. While normal spermiogram results had an L-carnitine mean value of 478.4.
- There was a significant statistically positive link between seminal plasma L-carnitine levels, the percentage of motile sperm, sperm count, and normal morphology.
These studies show that this amino acid is important for supporting several aspects of sperm health. This compound is needed to maintain healthy sperm density, morphology and movement.
Clinical Study: Does L-carnitine & L-acetylcarnitine supplementation improve male fertility?
Infertile men may be able to enhance sperm health by taking L-carnitine supplements according to research by De Rosa and colleagues3.
In this study, 170 infertile males received L-acetylcarnitine 500 mg twice daily and L-carnitine 1 g daily for 6 months. Levels of seminal carnitine were assessed. Researchers also measured sperm parameters such as motility, count, and DNA integrity.
The study found that
- After three months, all participants recorded better sperm quality. Total sperm count, sperm concentration, motility, nuclear DNA integrity, and morphology improved.
- A significant improvement in the capacity for sperm to penetrate the cervical mucus was also identified after six months of supplementation.
This research highlights the importance of this amino acid for supporting male fertility. Supplementation may improve sperm parameters the increase chances of fertilisation.
Clinical Study: Does L-carnitine lower oxidative stress on spermazoa
Sperm health can be negatively affected by free radical damage. A placebo-controlled, double-blind, randomized trial investigated the effects of carnitine on sperm kenetics and oxyradical scavenging capacity4
Fifty-nine patients were administered either L-carnitine, acetyl-L-carnitine, a combination of both acetyl-L-carnitine and L-carnitine, or a placebo.
The study found that
- Combination therapy of acetyl-L-carnitine and L-carnitine lead to an improvement on total oxyradical scavenging capacity and motility.
This study highlights the importance of this amino acid for minimising oxidative stress. Protecting sperm from free radical damage is essential for maintaining fertility.
Clinical Study: Can In-vitro fertilisation benefit from L-carnitine?
In preparation for IVF treatment, sperm typically undergoes in-vitro incubation and centrifugation. These processes are known to reduce human sperm quality.
In one study, researchers assessed the effects of L-carnitine on sperm viability. They focused on DNA oxidation and sperm motility following incubation and centrifugation5.
The study found that
- Sperm motility improved after incubation and centrifugation when 0.5 mg ml(-1) L-carnitine was added prior to centrifugation.
- Neither baseline sperm DNA oxidation or sperm viability were affected by the addition of this amino acid.
This research suggests that couples undergoing IVF treatment may benefit from carnitine supplementation. This amino acid may protect healthy sperm motility during in-vitro incubation and centrifugation.
Sources of L-Carnitine
L-Carnitine rich foods include red meat, pork, dairy, avocado, peanuts, asparagus, and wheat products. Red meats are the richest source of this compound.
When buying L-Carnitine as a supplement, branded ingredient “Carnipure®” is a recommended source, because purity is very high due to a patented fermentation process. Other qualities may result to include D-Carnitine, which is toxic when being taken in higher dosages.
Using Carnitine to improve male fertility
L-Carnitine is a powerful male fertility enhancing nutrient, but it is also just one of several so called fertility-neutraceuticals. Clinical research studies have consistently shown that
We have therefore compared all of the top male fertility combination supplements in a transparent, side-by-side evaluation.
VIDEO: How to improve sperm naturally with food
Sperm count, motility and morphology-enhancing nutrients
- “Mataliotakis, I. et.al. (2000). L-Carnitine levels in the seminal plasma of fertile and infertile men: correlation with sperm quality. International Journal Fertility and Women’s Medicine, Volume 45, Issue 3, (pp. 236-240).” ↩
- “Sheikh, N. et.al. (2007) L-carnitine level in seminal plasma of fertile and infertile men. Journal of Research in Health Sciences, Volume 7, Issue 1, (pp. 43-8)” ↩
- “De Rosa, M. et.al. (2005). Correlation between seminal carnitine and functional spermatozoal characteristics in men with semen dysfunction of various origins. Drugs in R&D, Volume 6, Issue 1, (pp.1-9).” ↩
- “Balercia, M. et.al. (2005). 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, Volume 84, Issue 3. (pp. 662-671).” ↩
- “Banihani S. et.al. (2012). Human sperm DNA oxidation, motility and viability in the presence of L-carnitine during in vitro incubation and centrifugation. Andrologia, Volume 44, Issue 1, (pp. 505-12).” ↩
- “http://humupd.oxfordjournals.org/content/14/3/243.full” ↩
- “Imhof, Martin et al., “Improvement of sperm quality after micronutritient supplementation” ↩