Meat and Dairy Intake Linked to Lower Testosterone in Men, Study Suggests
A new study from the University of Eastern Finland indicates a correlation between high consumption of animal protein and reduced testosterone levels, while plant-based protein shows an opposite trend.
Men who consume higher amounts of meat and dairy products may have lower testosterone levels, according to research published by the University of Eastern Finland. The study, which analyzed the diets of 2,546 men aged 42 to 60, divided participants into four groups based on their animal and plant protein intake.
The findings revealed that men with the highest intake of animal protein had, on average, lower total testosterone concentrations compared to those with the lowest intake. Conversely, a higher consumption of plant-based proteins, such as those found in legumes, grains, nuts, and seeds, was associated with higher testosterone levels. However, experts emphasize that the observed differences were marginal.
Testosterone plays a crucial role in men's health, regulating sex drive, muscle and bone strength, energy levels, and red blood cell production. Normal total testosterone levels in adult men are generally considered to be between 10 and 30 nanomoles per liter, with levels naturally declining by about 1% per year after age 30. Factors like obesity and type 2 diabetes can also contribute to reduced testosterone.
Further analysis indicated that a higher intake of dairy protein, particularly fermented dairy, was associated with lower total testosterone concentrations. In contrast, increased consumption of plant protein, especially from non-grain sources like vegetables and nuts, correlated with higher total testosterone.
While the precise mechanisms behind these associations remain unclear, researchers propose several possibilities. One theory suggests that individuals with higher plant protein intake may also consume more fiber and unsaturated fats, leading to healthier overall diets. Conversely, those with higher animal protein intake might consume more saturated fat and cholesterol. The study's authors noted, however, that these dietary factors did not entirely explain the observed results. Other potential influences suggested include differences in inflammation, insulin regulation, and the way testosterone circulates in the bloodstream.
The researchers concluded, "Higher animal protein intake was associated with lower circulating testosterone, whereas plant protein intake showed modest positive associations."