Study links organic Mediterranean diet to improved male fertility

By Dr. Sanchari Sinha Dutta, Ph.D.Dec 10 2023

Researchers in Italy have recently explored the beneficial effects of a low-carbohydrate organic Mediterranean diet on male fertility. Their study is published in the journal Current Research in Food Science. 

Study: Effects of the low-carb organic Mediterranean diet on testosterone levels and sperm DNA fragmentation. Image Credit: Aeril / Shutterstock

Background

Infertility is a significant healthcare problem, affecting around 8 – 12% of couples worldwide. About 50% of couples' infertility is associated with male reproductive complications. In addition to reproductive complications, unhealthy lifestyles and environmental toxin exposure are major contributors to male infertility.

Testosterone is the primary male hormone responsible for male sexual characteristics, spermatogenesis, and fertility. It plays a vital role in controlling testicular cell apoptosis and preventing sperm DNA damage. In obese men, low levels of testosterone, together with high levels of free radicals, have been found to trigger sperm DNA fragmentation.

Among various lifestyle factors, poor dietary habits are known to potentially affect fertility. However, no clear guidelines on dietary patterns are available for couples trying to conceive. The Mediterranean diet is regarded globally as the most beneficial dietary pattern for maintaining optimal health and reducing the risk of chronic diseases.

In this study, scientists have investigated the impact of consuming a low-carbohydrate organic Mediterranean diet on male reproductive health.

Study design

The study was conducted on 50 sub-fertile men, with an age ranging from 35 to 45 years. They were provided a Mediterranean dietary regimen, including 80% organic foods. Only carbohydrates with a low glycemic index were included in the diet.

Among 50 participants, 20 were separately instructed to reduce their carbohydrate intake to 35% of their daily calorie intake. All participants were asked to follow the diet plan for a period of three months.

The eating habits of all participants were assessed between 2020 and 2021. A food-frequency questionnaire assessed participants' adherence to the study diet. Blood and semen samples collected from the participants were analyzed to measure testosterone level and sperm DNA fragmentation index, respectively.

Important observations

The assessment of the pre-study eating habits of participants indicated a high intake of low-quality proteins and refined and high glycemic index carbohydrates. A high intake of coffee, dairy products, and processed foods was also observed among many participants.

Sperm DNA fragmentation and testosterone levels were measured after the implementation of personalized diet regimens for a period of three months.

A significant increase in testosterone levels was observed among participants who consumed lower amounts of refined carbohydrates and higher amounts of whole grains, fresh vegetables, and legumes while avoiding processed foods and dairy products.

Similarly, a significant reduction in sperm DNA fragmentation was observed among participants who consumed a 35% carbohydrate diet. This particular diet was rich in antioxidants because of the inclusion of red fruits and fresh vegetables. Similar to the other cohort, individuals in this group refrained from consuming dairy products and processed foods.

Study significance

The study describes the male reproductive health benefits of an organic Mediterranean diet rich in antioxidant and detoxifying foods, polyunsaturated fats, and whole grains. The diet considerably increases testosterone levels and reduces sperm DNA fragmentation.

Evidence indicates that testosterone level and carbohydrate and protein intake are inversely correlated. Reducing processed and dairy product intake and modifying carbohydrate intake in the study diet might be responsible for increased testosterone levels among participants.    

Furthermore, the study diet is enriched with antioxidants and vitamins, which play vital roles as non-enzymatic antioxidants to protect sperm DNA from free radical-induced oxidative damage.

Overall, the study finds that consuming a pre-conception low-carbohydrate and 80% organic Mediterranean diet rich in legumes, whole grains, and green leafy vegetables can benefit male reproductive health.