Sperm counts in men in Western countries have dropped by more than 50% in the last 40 years. A review and meta-analysis that included 43,000 men from North America, Europe, Australia, and New Zealand found that between 1973 and 2011, sperm counts have dropped by 52%. Men in South America, Asia, and Africa did not see any significant decline.
Why is this happening? The authors commented that “sperm count and other semen parameters have been plausibly associated with multiple environmental influences, including endocrine disrupting chemicals, pesticides, heat, and lifestyle factors, including diet, stress, smoking, and BMI. Therefore, sperm count may sensitively reflect the impacts of the modern environment on male health throughout the life course.”
This review specifically looked at sperm counts, not motility or morphology (movement capability and shape/integrity). Motility and morphology are other factors that can also impact male reproductive fertility, beyond just number of sperm. This is a staggering result—especially if the trend, already at 40 years, continues or accelerates. P. D. James’ 1992 novel, The Children of Men, actually used wide-spread male infertility as part of its plot for how society changes and tries to cope when faced with an inability to reproduce.
More research is needed as far as the causes and why it only seems to be happening in certain parts of the world. The environmental and lifestyle factors they mention definitely provide some clues. Oxidative stress/free radical damage is one of the well-known causes of lowered sperm counts and infertility. From 2015 studies, complete infertility rates (no sperm produced) among men vary from 2.5-12% of the population, depending on the part of the world.
Avoiding smoking, heavy alcohol and drug usage, and avoiding excessive heat in the genital area are some basic, sound strategies. A “balanced” approach to frequency of sexual activity is also linked to optimal sperm count and motility.
In terms of diet and supplementation, let’s look at a few recommendations shown to help keep sperm healthy. Nutrient dense foods with healthy fats like omega-3 DHA (US/CA), protein, vitamins and minerals (zinc, selenium, vitamin C) have been shown to help sperm health. Fresh fruits and vegetables with antioxidants, especially carotenoids like lycopene and lutein, are also excellent choices. Docosahexaenoic acid (DHA) is a specific omega-3 fatty acid that’s been found to help reduce DNA damage to sperm and improve antioxidant status. Research has also shown that infertile men have low amounts of DHA.
Ashwagandha (Withania somnifera) is one of the “all-star” herbs of Ayurvedic traditional medicine and research has corroborated many of its claimed benefits. Studies have found that it can reduce stress and, for men, both increase testosterone levels and increase sperm count and motility. From the world of antioxidants, coenzyme Q10 (or, ubiquinol, in its antioxidant form) research has been shown to increase sperm health and improve pregnancy rates. A small but promising study of astaxanthin found that it also improved sperm health and male fertility. Carotenoids like lycopene (found in tomatoes) and lutein (found in kale, spinach, egg yolks) have been shown in several studies to improve sperm health too.