Male Fertility · Male Factor Causes

Lifestyle, Insulin Resistance and Semen Quality as Co-Dependent Factors of Male Infertility

Zańko A, Siewko K, Krętowski AJ, Milewski R

Published December 30, 2022 International journal of environmental research and public health, 20(1)
DOI 10.3390/ijerph20010732 PMID 36613051 PMC PMC9819053

RRM Academy Synopsis

Lifestyle and insulin resistance both link to poorer semen quality

A 2022 review of studies from 1989 to 2020 found that lifestyle and insulin resistance are both linked to lower semen quality in men. It covers diet, weight, exercise, sleep, stress, smoking, alcohol and pollution. Few studies compare semen in men with and without insulin resistance.

Key Findings

  • In one included study, higher HOMA-IR (a score for insulin resistance) correlated with lower testosterone, lower semen volume and a lower percentage of progressively motile sperm.
  • In a study of body weight, 6% of men with normal BMI had oligospermia (low sperm count), compared with 17% of obese men.
  • Studies linked the Mediterranean diet and the DASH diet to better sperm counts, while processed meat and saturated fats correlated with worse semen measures.
  • Findings on physical activity conflict. Some studies found no effect, most reported a benefit from recreational activity, and cycling correlated with worse semen quality.
  • Studies reported that tobacco correlated with lower semen volume, sperm concentration, motility, morphology and total sperm count. Alcohol was linked to fewer morphologically normal sperm and sperm DNA damage.

Interpretation

The review gathers associations from many studies and reports no combined estimate. The authors write that lifestyle, insulin resistance and semen quality are interrelated, so cause and effect are hard to separate. Few studies look at semen quality in insulin resistance. Insulin resistance often comes with obesity and lifestyle factors. The authors call for studies that compare men with and without it. The review gives semen results in men and no pregnancy outcomes.

RRM Context

RRM looks for the underlying cause of infertility in both partners. A male metabolic factor fits that approach as a question to study. Unexplained infertility means the cause is undiagnosed. The review leaves open whether treating insulin resistance improves semen quality.

Abstract

Infertility is a problem that affects millions of couples around the world. It is known as a disease of couples, not individuals, which makes diagnosis difficult and treatment unclear. Male infertility can have many causes, from mechanical ones to abnormal spermatogenesis or spermiogenesis. Semen quality is determined by a number of factors, including those dependent on men themselves, with the number of infertile men growing every year. These include, e.g., diet, physical activity, sleep quality, stress, among many others. As these factors co-exist with insulin resistance, which is a disease closely related to lifestyle, it has been singled out in the study due to its role in affecting semen quality. In order to examine connections between lifestyle, insulin resistance, and semen quality, a review of literature published from 1989 to 2020 in the following databases PubMed/Medline, EMBASE (Elsevier), Scopus, Web of Science, and Google Scholar was performed. Hence, semen quality, environment, and insulin resistance are interrelated, thus it is difficult to indicate which aspect is the cause and which is the effect in a particular relationship and the nature of possible correlations. Since the influence of lifestyle on semen quality has been extensively studied, it is recommended that more thorough research be done on the relationship between insulin resistance and semen quality, comparing the semen quality of men with and without insulin resistance.

Topics

Related research

Male Fertility › Male Factor Causes › Lifestyle and Environment · Lifestyle and Environment › Nutrition and Metabolic Health › Blood Sugar and Insulin
Adrianna Zańko, Katarzyna Siewko, Adam Jacek Krętowski, Robert Milewski
A Zańko, K Siewko, A Krętowski, Bob Milewski, Rob Milewski, Bobby Milewski, R Milewski
PMID 36613051 36613051 DOI 10.3390/ijerph20010732 10.3390/ijerph20010732 Zańko et al. 2022, Zańko 2022