Exploring the Impact of Lifestyle on Male Fertility

In the intricate process of spermatogenesis, the testes continuously produce spermatozoa through a series of cellular phases. This process is regulated by various hormones essential for sperm development and function. Certain lifestyle factors can disrupt this delicate balance, affecting male fertility in numerous ways.

Understanding spermatogenesis

Spermatogenesis begins with spermatogonia in the seminiferous tubules, progressing through several stages until mature spermatozoa are formed. Hormones like gonadotropin  releasing hormone (GnRH), follicle  stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and dihydrotestosterone (DHT) play crucial roles in regulating this process. Any disruption in these hormonal pathways can impact spermatogenesis and fertility.

Lifestyle factors that can affect male fertility

Various lifestyle factors have been found to affect spermatogenesis.

Smoking, drugs & alcohol: Smoking cigarettes is linked to reduced sperm count, impaired sperm motility, and increased sperm DNA damage. Use of recreational drugs such as marijuana, cocaine, and anabolic steroids can negatively impact sperm production and quality. Excessive alcohol intake can lead to decreased testosterone levels, erectile dysfunction, and reduced sperm production.

Diet and Nutrition: Excess body fat can alter hormone levels, which can negatively impact sperm production and quality. A poor diet high in processed foods, trans fats, red meat, and sugars can impair sperm health. For their development, sperms require essential nutrients like zinc, selenium, folate, and vitamins C; D, and E.

Physical Activity:  While moderate exercise is beneficial, excessive or intense physical activity, especially cycling, can lead to overheating of the testes and reduced sperm production.  Conversely, a sedentary lifestyle can contribute to obesity and other health issues that impair fertility.

Heat: Frequent use of hot tubs, saunas, or long, hot baths can increase scrotal temperature, negatively impacting sperm production.

Environment: Exposure to environmental toxins such as pesticides, heavy metals, and industrial chemicals can impair sperm production and function.

Stress & Sleep: Chronic stress can interfere with the hormones responsible for sperm production, leading to reduced sperm quality and quantity. Poor sleep quality and insufficient sleep can negatively affect hormone levels and sperm quality.

Medications: Certain medications, such as chemotherapy drugs, some antibiotics, and antidepressants, can affect sperm production and quality.

Sexually Transmitted Infections (STIs): Untreated STIs can lead to inflammation, oxidative stress, and scarring that may block sperm passage.

Lifestyle, oxidative stress and sperm quality

We already know that unhealthy lifestyle choices can disrupt hormonal balance. In addition to that, another significant mechanism linking unhealthy lifestyle and fertility is the generation of reacytive oxygen species (ROS), e.g. after exposure to certain drugs and toxins. ROS, when present in excess, can cause oxidative stress. Oxidative stress leads to cellular damage, apoptosis, and reduced sperm function.

Additionally, increased ROS levels can result in DNA damage, reducing the ability of sperm cells to fertilize oocytes and impacting both natural fertility and assisted reproductive technologies (ART). Up to 70 % of subfertile men have been found to have oxidative stress in their reproductive tract.

It is important to understand that spermatozoa are among the first cells in the body to respond to oxidative damage. They are most vulnerable to oxidative assaults, because of their unique membrane composition. It has a very high proportion of polyunsaturated fatty acids that can be oxidized easily. In addition to that, sperms lose a big  proportion of their cytoplasm during their development. This is where defense and repair mechanisms are usually located. Therefore oxidative stress can impact sperm cells particularly strongly.

Understanding the mechanisms through which lifestyle factors impact fertility, such as hormonal dysbalance and oxidative stress, is crucial for developing strategies to mitigate their effects. By adopting healthier lifestyles, individuals can potentially improve their fertility outcomes and enhance their chances of conception.

Reference:

Rotimi DE, Singh SK. Implications of lifestyle factors on male reproductive health. JBRA Assist Reprod. 2024 Jan 30. doi: 10.5935/1518  0557.20240007. Epub ahead of print. PMID: 38289202.