How is sperm quality assessed? What are the causes for male infertility? Does nutrition affect sperm production?



One in six couples faces infertility issues. Today, the majority of subfertile couples seeks professional help. The fertility assessment of a couple is required after a year of regular, unprotected intercourse or in six months if the woman is over 35 years of age. Scientific research has shown that male problems are the most common reason of subfertility in couples. Those problems are caused by genetic factors and environmental factors, as line of work, nutrition, athletic supplements, medicines, smoking etc.

According to the diagnostic scheme of the World Health Organization, the parameters that
define male infertility are the volume of each
ejaculation, sperm count, motility and morphology. Processed meat consumption (smoked meat, cold cuts, sausages etc.) affects negatively the sperm morphology while the high-fat dairy consumption causes lower sperm density, especially in heavy smokers.


This may be a result of the trans fatty acids (a type of fatty acids mainly of animal origin), who are known to be associated with a lower sperm count. In addition to that, cholesterol, present in red meat, eggs and high-fat cheeses, is linked with lower ejaculation volume.

Men who prefer low-fat dairy products, especially milk, instead of high-fat dairy, have high sperm density and motility. Regular fish consumption raises sperm density and improves the morphology of the sperm. Sugar sweetened beverages (sodas, energy drinks etc.) have been shown to reduce sperm motility. A very common problem is also DNA fragmentation.

 Men with higher percentages of DNA fragmentation have lower chances of naturally causing a pregnancy, without medical help. The main cause of DNA fragmentation is oxidative stress, which is a result of many environmental factors, such as smoking, alcohol consumption, food additives, even inhaling exhaust fumes. Increasing your antioxidant intake is the most effective way of combating oxidative stress. Some antioxidants are vitamins A, C and E, polyphenols, flavonoids, iodine, manganese, zinc, Q-10 co-enzyme etc. Even though antioxidants seem to be the key to increasing male fertility, antioxidant supplementation does not often help and may even be dangerous. In case the intake of one antioxidant surpasses the DRIs, side effects or even unwanted hormonal changes may take place. This is why we should consider increasing the consumption of natural sources like fruits, vegetables, nuts, tea etc.

Hormones necessary for reproduction, such as testosterone, also indirectly affect male fertility. Low testosterone levels are a common finding in obese men who don’t have any other fertility related abnormalities. Hypotestosteronemia (low testosterone levels) associated with obesity is completely reversible with weight loss while testosterone supplementation therapy is NOT indicated because of possible severe side effects, such as sleep apnea or reducing fertility.

The parents’ pre-conception nutritional habits play a big role in the first stages of pregnancy. Deficiencies or excessive amounts of macronutrients (proteins, carbohydrates, fats) and micronutrients (minerals and trace elements) in this period can affect fetal development and the overall health of the child later in life. Especially for obese fathers, proper pre-conception diet is linked with both better sperm quality and increase in DNA integrity, as well as better neonatal health of the offspring. This is why, dietary changes should be seriously considered.
Advice for improving sperm quality:

Follow a well balanced dietary plan, like the Mediterranean Diet. Emphasize on fresh foods and reduce the consumption of ready-to-eat, pre-cooked meals and packaged products.

– Limit red meat intake to once per week, avoiding processed meat like cold cuts or smoked meat. Replace it with fish, once a week.
– Increase fruit and vegetable consumption by choosing them in different colors. By eating a “rainbow” of fruits and vegetables, you consume all the vitamins needed to produce better sperm.
– Prefer olive oil to any other kind of cooking oil or butter. Olive oil contains large amounts of vitamin E and very little saturated fats.
– Dried nuts and a small amount of dark chocolate (20g) can replace unhealthy snacks while providing you the antioxidants you need.
– Avoid as much as possible sugar sweetened beverages (sodas, energy drinks etc.). They have the tendency of altering metabolism and affecting directly the quality of your sperm, making it weak. You can refresh yourselves with water, green tea and fresh squeezed juices. You can also choose among the sugar free sodas, of stevia sweetened ones who have begun appearing in stores.

Ask your doctor for advice if you take any supplements. Athletic supplements may contain substances that cause unwanted hormonal changes. If you continue to take the supplement, never surpass the limit given by your doctor.
– Reduce smoking and alcohol consumption; both of them have been linked with lower sperm quality and low sexual performance.
– Exercise: it doesn’t only improve the sperm quality itself but it also regulates your metabolism, leading to weight loss. Low body weight is associated with better fertility rates as well as better offspring health.
– Avoid pressure. Tight undergarments or trousers, a badly designed bicycle seat, may cause infertility.