Do Low-Fat Diets Reduce Testosterone Levels?

low fat diet

Adequate testosterone levels are important for overall health. Low levels in men have been associated with the signs and symptoms below:

As well as a higher risk of developing some chronic diseases, like cardiovascular disease and type 2 diabetes. Some studies even suggest higher all-cause mortality (death) risk in men with lower testosterone levels.

PMID: 30145097, 29233816, 21816776

During the past 40 years, there has been a decline in testosterone levels in the general population that cannot be solely explained by traditional factors that are known to reduce testosterone, like obesity. 

Previous evidence suggests a relationship between dietary fat intake and testosterone levels, which might help partially explain this change.

A 2021 study conducted a meta-analysis of randomised controlled trials of low-fat diets and testosterone in healthy adult men

PMID: 33741447

pie chart

Researchers included trials that involved diets differing by at least 10% of total energy from fat with a duration of at least 1 week. 

Studies were included if they measured:

  • Total testosterone (TT)
  • Free testosterone (FT)
  • Urinary testosterone(UT)
  • Dihydrotestosterone (DHT)
  • Sex hormone-binding globulin (SHBG)
  • Luteinising hormone (LH)

No participants with testosterone deficiency were included.

Studies were NOT included if any factor that could affect testosterone levels such as:

  • Medications
  • Hormones
  • Supplements
  • Changes in exercise levels
  • Diets consisting of more than 20% protein
  • Diets consisting of less than 15% carbohydrate
  • More than 2 kg of weight loss
  • Difference in energy intake between diets higher than 10%. 

The researchers collected 6 trials including a total of 206 participants with an average age of 46 years. 

The researchers determined that 3 studies had a low risk of bias and 3 had a medium risk of bias.

Lower-fat diets led to a small decrease in total and free testosterone levels, compared to lower-carb diets. The testosterone dip was larger in studies conducted in Western countries.

Based on the meta-analysis of 6 studies, a low-fat diet, compared to a diet higher in fat, reduced the levels of total, free, and urinary testosterone, as well as dihydrotestosterone.

Western participants consistently experienced a reduction in testosterone levels after consuming a low-fat diet.

The only data from non-Western participants showed an opposite response, suggesting that genetics and background ethnicity might modulate the effects of diet on testosterone metabolism. 

Compared to a high-fat diet, a low-fat diet reduces testosterone and related metabolites in men, suggesting a decrease in testosterone synthesis. 

HOWEVER, the researchers only collected 6 studies that were all quite SMALL, leading to UNCERTAINTY in the estimates. More data and relevant studies would be useful to further shed some light and confirm this finding.

P.S You can buy any 3 items from our new range for £50 (saving you £25), We ship globally too.

Use code “RVSA50” to apply the discount.

rubgy shorts
Leave a Reply

Your email address will not be published. Required fields are marked *

For all support queries please email