The association between caffeine intake and testosterone: NHANES 2013–2014

[FunkOdyssey]

The association between caffeine intake and testosterone: NHANES 2013–2014​

Frank E. Glover, William Michael Caudle, Francesco Del Giudice, Federico Belladelli, Evan Mulloy, Eniola Lawal & Michael L. Eisenberg

Nutrition Journal volume 21, Article number: 33 (2022)

Abstract​

Background​

Caffeine is one of the most commonly used psychoactive drugs in the world, and provides many health benefits including alertness, improved memory, and reducing inflammation. Despite these benefits, caffeine has been implicated in a number of adverse health outcomes possibly due to effects within the endocrine system, effects that may contribute to impaired reproductive function and low testosterone in men. Previous studies have investigated associations between caffeine consumption and testosterone levels in men, although the quantity and generalizability of these studies is lacking, and the results between studies are conflicting and inconclusive.

Methods​

Using data from a cross-sectional study of 372 adult men in the 2013–2014 NHANES survey cycle, the researchers set out to characterize the association between serum testosterone levels, caffeine, and 14 caffeine metabolites.

Results​

Multivariable, weighted linear regression revealed a significant inverse association between caffeine and testosterone. Multivariable, linear regression revealed significant, inverse associations between 6 xanthine metabolic products of caffeine and testosterone. Inverse associations were observed between 5-methyluric acid products and testosterone, as well as between 5-acetlyamino-6-amino-3-methyluracil and testosterone. A significant, positive association was observed for 7-methyl xanthine, 3,7-dimethyluric acid, and 7-methyluric acid. Logistic regression models to characterize the association between 2 biologically active metabolites of caffeine (theobromine and theophylline) and odds of low testosterone (< 300 ng/dL) were non-significant.

Conclusions​

These findings suggest a potential role for caffeine’s contribution to the etiology of low testosterone and biochemical androgen deficiency. Future studies are warranted to corroborate these findings and elucidate biological mechanisms underlying this association.

Full Text:

The association between caffeine intake and testosterone: NHANES 2013–2014 - Nutrition Journal

Background Caffeine is one of the most commonly used psychoactive drugs in the world, and provides many health benefits including alertness, improved memory, and reducing inflammation. Despite these benefits, caffeine has been implicated in a number of adverse health outcomes possibly due to...

nutritionj.biomedcentral.com

 

[sammmy]

Usually the truth in the medical articles is buried in the Discussion section than in the Abstract:

Due to the cross-sectional nature of the study, this study cannot draw any true cause and effect conclusions between caffeine, its major metabolites, and testosterone levels. Additionally, the researchers are unable to determine the specific source of caffeine in this cohort (e.g. coffee, tea, soda etc.). Different sources of caffeine such as soda vs. coffee can present their own unique health profiles,

Lastly, using cross-sectional data this study unable to determine potential dose–response effects of caffeine on testosterone. As previously mentioned, studies have shown that for low dose of caffeine exposure, the effects on testosterone levels are positive, and for high caffeine levels inverse associations between caffeine and testosterone were observed.

 

[FunkOdyssey]

I'm adding it to my list of "Have you tried X?" questions that I ask people with low testosterone before they start TRT. I think there's enough smoke here that if you had low T together with substantial caffeine intake you ought to explore that connection.

Forget all of the biochemical interactions they describe at the level of the testes -- the effects of caffeine on sleep quality alone could trash your levels.