Diabetes and Weight Affect Male Fertility

Several studies have shown a link between female infertility and obesity. Female diabetes has been linked to miscarriage and birth defects. Little data has been published on the effect of male weight and infertility. A new study shows diabetes and being overweight has a negative effect on male fertility.Diabetes is a disease associated with high blood sugar. The body normally produces a hormone called insulin, which regulates blood sugar and keeps it low. People can develop diabetes from a failure to make insulin (Type 1) or resistance to insulin (Type 2). The most common reason that people develop insulin resistance is being overweight or obese.

In the last few decades, a higher percentage of Americans have become overweight. As a result, the rate of diabetes is increasing by a huge amount.

Sperm DNA Damage

A study conducted out of Belfast, Ireland was presented at the European Society for Human Reproduction and Embryology. The research suggests that semen from diabetes patients looks normal under the microscope, but when examined more closely and compared to men with proven fertility, the sperm DNA seems to be significantly altered.

DNA is the hereditary material located in cells. Some of the DNA is divided into discrete portions called genes. Each gene has a unique function. For the function of the gene to be carried out, the cell takes the information in the DNA and first converts it into a similar material called RNA. The RNA is then used as a template to make proteins. The proteins produced actually carry out the numerous functions in a cell. If the DNA or RNA in a cell is damaged, the protein produced may be present in lower amounts or not function correctly in the cell.

Sperm are responsible for carrying male’s DNA to the female egg. At the time of fertilization, the male and female DNA are combined. The combined DNA contains all of the information necessary for that embryo to develop into a human being.

Since sperm are produced continuously all during a man’s life, in the testes, there is a constant process of DNA being made and packaged into sperm. The testes contain many proteins to help with the process of making sperm. Some of these proteins are thought to reduce the amount of damaged DNA.

In this study, researchers found a fourteen-fold decrease in the amount of a protein enzyme called ornithine decarboxylase, which is responsible for the production of spermine and spermidine, compounds responsible for cell growth that help stabilize the structure of DNA in sperm. This indicates that having diabetes has a direct influence on the health of semen.

Possible Cause of RNA Damage

The researchers uncovered that a group of compounds known as AGEs (Advanced Glycation End Products) was found in the male reproductive tract. This substance is known to accumulate in men as they age. It is also dependent on lifestyle choices such as smoking, diet, and in many diabetic complications, they are centrally linked to DNA damage. Scientists are still not quite sure how these compounds play a role exactly. They have still yet to determine how these AGEs cause and contribute to the DNA damage.

As a precaution for protecting sperm, they are now trying to reduce the amount of AGEs in the body. This could include changes in diet, disrupting the production of AGEs, or increasing protection against AGEs through dietary supplements.

Obesity and Being too Thin affects sperm

A separate study suggested that being too thin or having obesity, a condition often associated with diabetes, also had a negative effect on the health of a man’s sperm. The study found that overweight men had less seminal fluid and more abnormal sperm. Men with an optimal weight had higher levels of sperm and a higher semen volume. The research did not look at the quality of DNA, however.


With the number of diabetics at younger ages increasing, it is important to know the effects of the disease, how they impact the body, and more specifically, how they affect fertility.

Often, type II diabetes and obesity can be controlled and even reversed by changes in lifestyle. It is important that men achieve an ideal body weight before trying to conceive to increase their chances of pregnancy. This can be done with healthier eating choices, lower sugar intake, and an increase in exercise.

Women should not be discounted as well. There have been studies that show overweight women have lower IVF success rates. For the best pregnancy success rates, it is important that both parents are at a healthy weight.

It has always been known that staying around a healthier weight is beneficial to our in many ways. For men, the increased chances for improved semen quality are just another benefit to add to the list.

Similar Posts