New research shows that consuming large amounts of ultra-processed foods can negatively impact men’s reproductive health by reducing sperm quality, while also contributing to metabolic issues like weight gain and high cholesterol.

Published on August 28 in Cell Metabolism, the study found that eating ultra-processed foods lowered key hormones involved in sperm production—even when calorie intake was the same as diets rich in unprocessed foods.

Quality Over Calories

Dr. Philip Werthman, a urologist specializing in male fertility in Los Angeles, explained to Healthline:

“It’s not just how many calories you eat, but where those calories come from that affects your health.”

Study Design and Key Findings

The study involved 43 men between ages 20 and 35. Each participant spent three weeks eating mostly ultra-processed foods and three weeks eating primarily unprocessed whole foods, with a three-month break between diets. Some men also consumed an extra 500 calories daily to test the effects of higher intake.

Men on the ultra-processed diet gained over a kilogram and increased their body fat. Their testosterone and follicle-stimulating hormone (FSH) levels—both essential for sperm production—decreased. The researchers also detected higher levels of cxMINP, a hormone-disrupting chemical linked to plastic packaging often found in processed foods.

A Link to Declining Sperm Counts

Since the 1970s, global sperm counts have dropped by about 60%, a trend that coincides with the rise in ultra-processed food consumption and exposure to endocrine-disrupting chemicals. This study adds important evidence to that connection.

Kristin Kirkpatrick, a dietitian at Cleveland Clinic, noted:

“Even healthy men can experience hormone imbalances from eating too many processed foods.”

Dr. Werthman added:

“Your reproductive health is closely tied to your overall wellness. Metabolic problems like obesity and high cholesterol can hurt sperm quality.”

Broader Health Risks

According to the CDC, ultra-processed foods make up roughly 55% of calories consumed by Americans. These foods tend to be high in sugar, salt, and unhealthy fats, while low in fiber and nutrients. Common examples include fast food sandwiches, sweetened drinks, packaged snacks, and baked goods.

Studies link these foods to obesity, heart disease, type 2 diabetes, stroke, cognitive decline, and thousands of preventable deaths annually.

How to Protect Male Reproductive Health

Experts recommend:

• Eating whole, nutrient-rich foods like fruits, vegetables, and whole grains

• Exercising regularly and maintaining a healthy weight

• Avoiding tobacco and limiting alcohol consumption

• Getting enough sleep and managing stress

• Minimizing exposure to heat sources like saunas and hot tubs

Dr. Werthman concluded:

“Your reproductive system is a reflection of your overall health. Making healthy lifestyle choices is essential.”