The 4 Top Fertility Supplements for Men - Can They Be Harmful?

The 4 Top Fertility Supplements for Men - Can They Be Harmful?

While most people have heard about the significant drop in male fertility over the last few decades, few people expect it to directly affect them. However, according to the National Institutes of Health, in the last 70 years since records were first taken, the male sperm count has decreased every year by at least 1.5%.[1] In the U.S., there are now more than six million infertile couples, or 10% of couples between the ages of 18 and 38.[2] The National Institute for Health and Clinical Excellence in the UK found that the situation is even more acute; infertility affects one in seven couples, and amongst the couples going for IVF treatment in the UK, roughly half are infertile because of the man.

While the common assumption is that sperm count is the only indicator of fertility, male fertility is in fact determined by measuring the quantity, quality, and mobility of sperm. Quality refers to the shape and structure of the sperm, and infertile men may have a large percentage of deformed sperm. Motility refers to the ability of the sperm to move, and infertile men may have a large number of sperm which does not move at all.

According to the U.S. National Library of Medicine National Institutes of Health, the principal reason for up to 80% of male infertility (and subfertility – diminished reproductive capacity) is the damaging effects of oxidative stress on sperm, which occurs due to environmental factors such as pollution, and lifestyle factors, such as smoking, stress and poor diet.[3] In addition hardwired genetic factors or previous infections can be causative factors.

Research was carried out in October, 2011 at the Harvard University and the University of Murcia to examine the effects of diet on male fertility. The findings of the research were presented at the Annual Meeting of the American Society for Reproductive Medicine.  The studies showed that poor nutrition can have a negative effect on sperm movement. Audrey Gaskins of Harvard School of Public Health’s department of nutrition, said: “the main finding of our work is that a healthy diet improves sperm motility and overall sperm quality. Specifically, this means a diet of higher fish, fresh fruit, whole grains, legumes and vegetables seems to improve sperm motility

Most men who are diagnosed as having poor quality sperm turn to supplements that purport to increase fertility. There are a large number of supplements on the market that are recommended for infertile men, and the four most commonly taken ones are reviewed below. While all of the supplements below can aid male fertility, it is of vital importance that the man is aware of the possible side effects, and the maximum recommended doses.

Acetyl L-Carnitine

This supplement is taken for a wide variety of conditions as it acts as a powerful antioxidant. It is an amino acid which is essential for the normal functioning of sperm cells, and research has shown that low sperm counts have been linked to low L-Carnitine levels in men. A link has been made that the higher the levels of L-Carnitine in the sperm cells, the better the sperm count and motility. For this reason and due to that fact that it is not expensive, it is the first amino acid supplement that infertile men turn to.

Side Effects

There are a number of possible side-effects of L-Carnitine that you need to know about. They range from mildly uncomfortable to life-threatening, including nervous system dangers, renal system dangers, and gastrointestinal dangers such as stomach cramps, diarrhea, nausea.

Get more detailed information about all these side-effects at:

Vitamin E

Vitamin E is powerful antioxidant which has been shown to increase male fertility. With our pesticide laden foods less nutritious than ever, the Linus Pauling Institute at Oregon State University said: “more than 90% of Americans do not get the daily dietary recommendations for vitamin E.”[4] As a result, some men use this supplement in a bid to increase their fertility.

Side Effects

Some people think that when it comes to the ‘harmless’ vitamins such as vitamin E, there cannot be too much. However, some companies sell vitamin E supplements with doses of 400 ml per day or more, and this is simply too high a dose. Authors Briggs et al. of the book Food and Nutrition in Australia said that while vitamin E is relatively non-toxic, a number of negative effects have been found with daily intakes of 300 mg of synthetic vitamin E, including gut problems, problems with blood clotting, exhaustion, and a general feeling of being unwell. Edgar Miller, an associate professor of medicine at the Johns Hopkins University School of Medicine, said that “our studies show that the use of high-dose vitamin E supplements do not prolong life but is associated with a higher risk of death.”[5]

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Zinc is commonly referred to as the ‘killer’ fertility booster and the first one that most men turn to. Zinc helps to maintain semen volume and testosterone levels, keeping sperm healthy. As part of this, it helps promote sperm motility and concentration, and this claim was substantiated by a FertilAid for Men study in 2007.[6] Zinc is also significant in that it provides for the smooth functioning of the prostate glands, and a zinc deficiency can lead to prostrate difficulties.

Side Effects

The National Institutes of Health say that an adult should not take more than 40 milligrams of zinc per day from foods and supplements combined.[7] In a bid to increase fertility, some men take 150 milligrams to 450 milligrams of zinc per day. The Institutes have linked such high doses of zinc with low copper, iron and magnesium levels, as these minerals cannot metabolize in the presence of high levels of zinc. This in turn can decrease your body’s immune function. High zinc doses may also increase the risk of urinary tract problems, including infections.

Many zinc products such as sprays also contain another metal called cadmium. According to a study by the National Institutes of Health and other academic research institutions, exposure to high levels of cadmium can, ironically, have a detrimental effect on human fertility.

According to MedlinePlus, taking more than 40 mg per day of zinc is “likely unsafe,” and leads to a variety of ailments such as stomach pain, fatigue, and other such problems. In addition, it can have a detrimental effect on good cholesterol levels, whilst raising the level of bad cholesterol.

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The Department  of Medical Embryology at the University of Rome released a report in early 2012 outlining how selenium is a key element in spermatogenesis and male fertility.[8] Selenium is required for the production of healthy and active sperm, and it can be lost due to frequent ejaculation because it is released with the seminal fluid.

Side Effects

Selenium is a trace mineral, which means that the human body needs only a very small amount to function properly. The fact is that most people get enough selenium through food, and a high selenium intake can cause serious side effects.

Excessive selenium intake can cause some dangerous side effects, which can occur as a result of selenium toxicity. These most common of these side effects include: nausea, vomiting, and abdominal (stomach) pain, hair loss, a metallic taste in the mouth and weight loss. In the worst cases selenium toxicity can lead to heart failure. This however is rare, and according to ACU-cell nutrition (a clinical research resource) it only becomes a concern at higher amounts. The main problem with selenium is its antagonism to other nutritional factors such as chromium and magnesium. This means that when taken on its own, it can inhibit the absorption of other nutrients.

Read more about these side effects here:

So Do Supplements Really Help Fertility?

A 2011 study conducted in New Zealand found that men with low fertility can greatly enhance their chance of getting their partners pregnant if they take a small but regular dose of vitamins, antioxidants and mineral supplements.[9]

The researchers took data from more than 34 studies involving over 2,850 couples who were using reproductive techniques such as IVF.

This study and many others proceeding it have proved that supplements are an important part of fertility treatment for men. When starting a course of supplements, all men should consult with their doctor and get up-to-date information on the recommended dose for the supplements, and not exceed this level. Taking supplements at the right amount can be greatly beneficial, but taking them in excessive doses can be greatly harmful.