Post Date December, 03 2023
A new study released at the European Conference on Human Reproduction and Embryology in Barcelona, Spain, shows that obese men have more inferior sperm than men with normal waist circumference. This also directly means that the larger the male waist circumference, the poorer their reproductive ability, and in severe cases, may even lead to infertility.
The research team of Gias Shayeb from the University of Aberdeen in the UK analyzed the sperm of more than 5000 men in Scotland, and divided them into different groups based on a body mass index (BMI), which is the square of their weight (kilograms) divided by their height (meters). BMI between 20 and 25 is normal weight, 25 and 29 are overweight, and 30 and above are obese.
The results showed that men with a BMI of 20 to 25 had higher levels of normal sperm, while overweight and obese individuals not only had lower sperm counts (sperm counts), but also had fewer normal sperm counts. Obese men are more than 60% likely to have fewer sperm, while their chances of carrying abnormal sperm are also more than 40%. The situation of overweight men is similar to that of obese men. In their study, Shayeb et al. excluded other factors that may affect sperm count, such as smoking, alcohol consumption, drug abuse, and age, confirming that obesity does affect sperm count and sperm quality.
Why does obesity affect the quantity and quality of men's sperm? There are currently some theories and hypotheses, among which three are more commonly recognized. One is that adipose tissue can affect sexual hormone metabolism, which may hinder sperm production and sperm quality. Second, temperature may have a negative impact on sperm production. The normal temperature of a person is around 37 ℃, and the optimal temperature for sperm production is 2 ℃ lower than the normal temperature. Obese men have more fat, so their body temperature is higher than normal. High temperature in the scrotum can directly affect the spermatogenic ability of the testis, resulting in reduced sperm production; Even if the number of sperm produced is not affected, the quality of sperm after production will also be affected.
Poor sperm in diabetes
It is worth noting that diabetes or recessive diabetes can also damage sperm and thus affect male fertility, and obesity is one of the main incentives for diabetes. Research by other researchers has confirmed this. When Cohen Maridis of Queen's University Belfast treated 40 men who were not overweight but suffered from diabetes, he found that because of diabetes, the blood sugar level of the patients was high, which damaged the DNA in their sperm. They found that people with diabetes were twice as likely to have sperm damage as normal men without diabetes.
Still, researchers cannot confirm that obesity necessarily causes infertility, depending on other factors. For example, if a obese man marries a normal woman, the fertility function of the obese man will be compensated by the other party, and therefore it does not necessarily lead to infertility. However, if obese men are combined with obese women, their obesity will overlap and form a magnifying effect, resulting in infertility.
(Intern Editor: Cai Junyi)
