Testosterone is an important hormone for men’s health. It affects muscle mass, bone strength, blood cell counts, energy levels and sex drive. If testosterone levels are too high or low, it can cause problems like infertility, acne, erectile dysfunction, and low libido.
Does the environment impact your testosterone levels? A new study from the University of Durham in the UK suggests that the environment boys grow up in, rather than their genetics or ethnic background, is the most significant factor affecting their adult testosterone levels.
Let’s find out what the study says about the role of the environment and its impact on testosterone levels.
Environment Impact on Testosterone – A Study Examining the Factors
Researchers have known that testosterone levels go up and down based on life events. Getting married, becoming a father, stress, or other things can make testosterone levels jump around. However, scientists still don’t fully understand why testosterone levels are different in various populations of men.
Research published in Nature Ecology and Evolution, led by Dr Gillian Bentley and colleagues at Durham University, tries to find the impact of the environment on testosterone levels. They compared testosterone levels among five groups of men with different genetic backgrounds and childhood environments:
- Bangladeshi men born, raised, and still living in Bangladesh.
- Bangladeshi men born in Bangladesh who moved to the UK as children.
- Bangladeshi men who migrated to the UK as adults.
- UK-born men of Bangladeshi migrant parents.
- UK-born men of European heritage.
The researchers measured testosterone levels in samples from 359 men across these groups. They also examined each man’s height, weight, and age of puberty onset.
The following are the Key findings:
- Bangladeshi men who grew up in the UK had significantly higher testosterone than those raised in Bangladesh
- Bangladeshi UK migrants also reached puberty earlier and were taller than non-migrants
- Men who moved to the UK as adults had lower testosterone than those who migrated as children
Interpretation Of Environmental Impact on Testosterone
The study reveals several key insights into how environmental factors can influence testosterone levels in men.
1. Living in Impoverished vs. Industrialized Areas Impacts Hormone Levels
The researchers suggest living in impoverished areas with high disease exposure and malnutrition diverts energy from optimal growth and testosterone production. The body enters ‘survival mode’, where resources are allocated to fighting infection and overcoming poor nutrition rather than investing in hormones like testosterone. In contrast, growing up in more industrialized and sanitary regions with abundant food allows the body to devote more energy to growth, development and testosterone generation.
2. Factors That Determine Testosterone Levels
While childhood environment, disease, and nutrition exposure are the major influences on testosterone, genes still play a contributory role. There is evidence that certain genetic markers correlate with testosterone levels within populations. Additionally, some inheritance of testosterone levels occurs down family lines, suggesting heritable genetic factors. However, this study found childhood environment to be the predominant determinant of variation between different groups.
3. Childhood Surroundings Influence Hormone Levels Later in Life
The study found that men’s testosterone levels are largely set during childhood through puberty, and this baseline persists into adulthood. However, older boys may continue to gradually adapt their testosterone to their surroundings even into their late teens, which was somewhat later than expected. This indicates a developmental window where the childhood environment shapes testosterone levels, which has a sustained impact lasting throughout the lifetime.
4. Implications for Screening of Testosterone-Related Conditions
The findings have important implications for health screenings and monitoring testosterone-influenced conditions. Men who migrated from impoverished to industrialized areas in childhood may need more frequent prostate screening, as their higher testosterone levels raise the risk for this condition. But alongside screening, a man’s childhood surroundings and exposures should also be considered when assessing conditions linked to testosterone.
5. Insights Into Declining Testosterone Levels in Western Men
The research provides valuable insights into declining testosterone levels in men from certain Western countries. It indicates that improved early life conditions do not fully explain this decline. However, factors like lower rates of smoking and obesity in these countries likely contribute to the ongoing decrease. Additionally, there may be gradual “generational” effects where testosterone levels sink closer to non-migrant levels over multiple generations born in industrialized regions. More research is still required to untangle the many influences responsible for this downward trend.
In summary, this comprehensive study emphasizes the substantial impact of childhood environment, especially disease exposure and nutrition, in shaping men’s testosterone levels in adulthood. It highlights how early life conditions can affect male health for decades. These insights have value for understanding testosterone differences between populations and screening those at higher risk of related illnesses. However, genetics and adult lifestyle choices also contribute to testosterone levels.