More and more couples postpone having children until later in their lives. It may seem like a wise decision until we look at the statistics which shows that increasing age affects fertility both in men and women. When it comes to the actual infertility prevalence between sexes, the male factor accounts for approximately 50% of the cases(1 - see references to the side).
Can fertility be influenced by anything else apart from the age? The answer to this question is yes. Unfortunately, sperm counts have significantly dropped in the last 50 years, which is suggestive of mainly environmental and lifestyle causes rather than genetics2.
Eugenia Grand, a Specialist Dietitian in Fertility and Pregnancy and a treasurer for BDA Maternal and Fertility Nutrition Specialist Group, shares her views about what men can do to prevent infertility in the future or improve their current reproductive health.
Follow a healthy, balanced diet
Men who consume a Mediterranean style diet have been found to have a better sperm quality and lower infertility rates3. The Mediterranean diet consists of a variety of fruit and vegetables, nuts, wholegrain breads and cereals, pulses, and seeds. Moreover, it is low in saturated fat that usually comes from dairy and meats, and high in mono- and polyunsaturated fats that come from seafood and oily fish. Alcohol is consumed in moderation.
Eat your 5-A-day
This food group deserved a separate mention because fruit and vegetables contain a variety of vitamins (vitamin A, C, E) and phytochemicals (Carotenoids, Flavonoids Anthocyanins etc.) that act as dietary antioxidants playing a protective role in spermatogenesis. There is plenty of scientific evidence that confirms the benefits of fruit and vegetable intake for sperm quality4.
Eat nuts daily
Nuts are a rich source of various vitamins (Folate), minerals (Iron and Zinc), and healthy fats (Omega-3). The California Walnut Commission, a current strategic partner for the BDA, have been continuously supporting health-related research on walnuts for the last 30 years. One such scientific trial established that 75g of walnuts per day added to a Western-style diet over a period of 12 weeks improved sperm vitality, motility, and morphology in a group of 117 healthy young men aged between 21-355. The result of this study showed a beneficial cumulative effect of multiple nutrients in a single food. The 75g daily walnut portion did not cause any weight gain in participants.
Keep your weight in a healthy range
Being obese is a risk factor for several chronic conditions, like cardiovascular disease and diabetes. Moreover, some epidemiologic studies have found a higher incidence of male factor infertility in obese males6. This association is thought to be due to hormonal imbalances, direct effect on reproductive organs, and disruption of spermatogenesis7. To improve fertility, it is advisable to optimize the BMI by following a healthy diet and taking regular exercise.
According to the NHS, adults should do some type of physical activity every day and aim for at least 150 minutes of moderate-intensity activity a week or 75 minutes of vigorous-intensity activity a week8. However, if you already have problems with fertility (e.g. varicocele and abnormal semen parameters) it is not advisable to participate in regular intense exercise9.
It has been known for a while that elevated temperatures in scrotum negatively affect sperm quality, however, the mechanisms behind this process are poorly understood. To protect sperm quality, it is currently recommended to avoid prolonged periods of sitting, taking hot baths or showers, and wearing tight-fitting underwear10.
For more information about healthy eating or weight loss:
More about standard serving sizes for nuts:
Recipe from California Walnut Commission by Nic’s Nutrition (BDA member)