Male Infertility - Unique Supplement Options
by: Rochelle Fernandes, Msc, ND (cand.)
There is a new, growing interest in the field of male infertility, given the recent trends of declining conception over the past decade. The times are telling of families having fewer children, later in age and often having more difficulties with conception. Infertility can pose physical, psychological, financial and economic burden on individuals, the health care system and society. Historically, female infertility carried most of the focus, however, more recently alarming male statistics cannot be ignored. For instance, 40% of infertility is attributed to males .
There are several causes of infertility for males. These include but are not limited to chronic inflammation, environmental toxicity, hormonal dysfunction, metabolic syndrome, oxidative stress and genetic causes.
Overview of Treatments
There are numerous treatments for male infertility, each designed to target some of the causes named above. These can consist of surgery to fix blocked tubes, aids that deliver sperm to the female, lab induced fertilization of an egg, medication and natural supplements.
There are several nutritional supplements and other natural treatments that can aid in the prevention and improvement of impaired fertility. These include vitamins that are well known, such as vitamins C, E, and Zinc. There are also more complex supplements, such as L-carnitine and coenzyme Q10. The last group of supplements fall into the category of nutritional metabolite/ingredient, such as lycopene or beta carotene. Many of these supplements have shown promising research for the ‘chronic inflammation’ and ‘oxidative stress’ theories of infertility.
What roles do Vitamins C, E and Zinc have?
The most common uses of vitamin C are for the common cold, allergies, burns and now even cancer prevention. The recommended daily intake for adults is 90 mg. Food sources of vitamin C include citrus fruits, Swiss chard, broccoli, strawberries and many more . Vitamin C is a cofactor in collagen regeneration. Collagen is found in blood vessels, the skin and ligaments. It also plays a large role in amino acid metabolism and hormone formation. It promotes the absorption of iron and calcium within the body . The use of vitamin C for fertility is based on its antioxidant capability. Antioxidants prevent free radical buildup, as well as promote the elimination of free radicals. This helps with optimal sperm formation and better functional development.
Vitamin E also has a major antioxidant function. The recommended daily intake for adults is 15mg. Two types of vitamin E exist: the natural and synthetic forms, of which the natural form is thought to be more potent. Food sources of vitamin E include wheat germ, sunflower, safflower, corn and soybean oils, as well as spinach and broccoli.
Zinc is an important mineral. The recommended daily intake is 8-12mg. It is used to strengthen the immune system and helps with wound healing. Food sources of zinc are seafood, beef, lamb, spinach, nuts and seeds.
Evidence for vitamins C, E, Zinc
Several studies have shown that lower baseline levels of certain anti-oxidants have contributed to male infertility. One study showed that infertile males had a significantly lower intake of zinc/folate compared to controls (p<0.001). Moreover, intake of vitamins C/E were lower than daily recommended doses in 59.4% of infertile males versus controls (p<0.05). This study also showed mechanisms of action and how lower intake of these vitamins could alter the shape/motility of the sperm. For instance, significant correlations were found between folate (r=0.5, p<0.001), zinc (r=0.6, p<0.001) and percentage of motility, and also between vitamin E and morphology(r=0.3, p=0.03), zinc and concentration (r=0.4, p=0.004) in all subjects .
What is L-Carnitine?
L-carnitine is an amino acid that is produced by the body. Beef, chicken and milk are good food sources of this ingredient. The role of L-carnitine in the body is to transport long chain fatty acids into the mitochondria, which is the power house of the cell. L-carnitine is well known in use for heart disorders, such as post myocardial infarction, congestive heart failure, muscular conditions, brain disorders and many more uses, including fertility as a newer consideration. The average intake of L-carnitine will vary depending on the use, but can often range from 1-3g .
Evidence for L-Carnitine
There is also promising evidence for improvements in sperm anatomy and movement from L-Carnitine supplementation. One systematic review/ meta-analysis compared L Carnitine to placebo and showed significant improvement in pregnancy rate (OR = 4.10, 95% CI (2.08, 8.08), p< 0.0001), total sperm motility (WMD = 7.43, 95% CI (1.72, 13.14), p = 0.04, and forward sperm motility (WMD = 11.83, 95% CI (0.49, 23.16), p = 0.04) . Another group suggests this same theory; proposing that antioxidant use, such as L-carnitine would improve pregnancy rates at 4.18, with a 4.85-fold improvement in live birth rate .
What is Coenzyme Q 10?
Coenzyme Q10 is a molecule that is naturally produced by the body and can be taken as a dietary supplement as well. Food sources of Coenzyme Q10 include soy oil, peanuts, beef and organ meats. The supplement is more commonly used in cardiac disease, such as myocardial infarction and congestive heart failure, similar to L-carnitine, as well as can be used for metabolic disorders, cancer and muscular dystrophy . Its new role in fertility is thought to originate as from theories of its use as an energy derivative for sperm development and through related mechanisms of action.
Evidence for Co-enzymeQ10
There is a strong body of evidence for coenzyme Q10 (CoQ10) and various aspects of male infertility; more specifically it is thought to improve sperm shape and function. Coenzyme Q10 and ubiquinol increased significantly in both seminal plasma and sperm cells after treatment, as well as spermatozoa motility in one double blind, randomized, placebo controlled trial . Another study showed that there were great improvements in sperm concentration and motility after coenzyme Q10 treatment. Treatment resulted in 48 (28.4%) partner pregnancies, from those, 16 (9.5%) were spontaneous. There were immense improvements in sperm concentration and motility after 3 and 6 months of treatment . Another retrospective study with 62 patients who had received 100 mg coenzyme Q10 twice a day for six months due to idiopathic infertility showed changes in morphology and motility that were statistically significant (P < 0.00) . Overall, the research does support a well-grounded link through direct correlations between CoQ10 concentrations and sperm motility .
What are the roles of beta Carotene and Lycopene?
Carotenes are a unique group with strong antioxidant properties; these include lycopene, lutein, astaxanthin and β-carotene. These antioxidant properties enable these molecules to help individuals combat chronic disease. Studies have shown that Astaxanthin is a stronger antioxidant compared to β-carotene, vitamin E and vitamin C, respectively 54, 14 and 65 times as measured .
Food sources of this group includes carrots, tomatoes, dark leafy greens, grapefruit, red peppers and sweet potatoes. Both the carotenes and lycopene have been thought to be useful in cancer and cardiac disease. Beta carotene has been used for macular degeneration, while lycopene is a candidate for benign prostate hyperplasia and prostate cancer. A new interest of these molecules in fertility are due to their high antioxidant capability.
Evidence for Beta Carotene and Lycopene
One study showed that B carotene intake was associated with higher sperm motility and, in the case of lycopene, better sperm morphology . More specifically, they showed that progressive motility was 6.5 (95% confidence interval [CI], 0.6, 12.3) percentage units higher among men in the highest quartile of β-carotene compared to the lowest quartile. Lycopene intake was positively associated with sperm morphology. Another study showed that there was a positive association intakes of vitamin C (P (trend) = 0.04), lycopene (P (trend) = 0.03) and β-carotene (P (trend) = 0.04) and total motile sperm count. The semen volume increased with higher intakes of vitamin C (P (trend) = 0.04) .
Collectively, Vitamins C, E and Zinc, L-Carnitine, Coenzyme Q10, the carotenes and lycopene have shown promising potential though vast numbers of studies. Although further studies are needed with greater statistical power, the studies mentioned above are a sample of the research that is out there. It is hoped that these supplements can be used on their own or alongside medication or other fertility treatments to treat several causes of infertility for males.