How Much Caffeine Can Affect Erectile Dysfunction?

Review

Caffeine Intake and Erectile Dysfunction in US Men

[PLoS ONE 2015; 10(4):e0123547]

Summary

This correlation of caffeine intake and erectile dysfunction found men who drank approximately 2-3 cups of coffee per day had the lowest of odds of developing erectile dysfunction.

Study Methods

The study of 3,724 men who participated in the National Health and Nutrition Examination Survey (NHANES) who were analyzed for their self-report of erectile dysfunction compared to their 24-hour dietary recall history to estimate caffeine intake. Using multi-variable logic regression analysis, the men were able to be categorized for correlation.

Results

This analysis found men who drank between 85mg and 170mg a day (3^rd quintile) and 171mg to 303mg a day (4^th quintile) of caffeine were less likely to report erectile dysfunction than men who had the lowest caffeine intake (0-7mg a day). The odds ratio for developing erectile dysfunction in the 3^rd quintile was 0.58; (95% CI, 0.37-0.89); and 4^th quintile OR: 0.61; 95% (CI, 0.38-0.97). Additionally, the researchers found overweight and obese men, as well as hypertensive men who consumed over 85mg a day of caffeine had lower rates of erectile dysfunction compared to less or no caffeine. This only held true for those overweight/obese men and hypertensive men who did not have diabetes.

Conclusion

Two to 3 cups a day for men, even overweight and obese men without diabetes, lower the risk of developing erectile dysfunction. This is just the latest study to look at the potential benefits of caffeine in other conditions including liver disease, and interestingly, all cause mortality. (NEJM 2012. 366; 20: 1891).

Discussion

In this interesting use of the large NHANES dataset, the authors found caffeine intake (mostly from coffee) correlated with erectile dysfunction. Over 2 cups per day seemed to have the most protective effect. This is after adjusting for likely confounders.

This is an observational study of a large data set, so no cause and effect can be inferred. However, the results show that intake of caffeine can be recommended to men, especially obese or overweight without diabetes who are concerned about erectile dysfunction.

Why would caffeine affect erectile dysfunction? The study’s authors theorize that caffeine triggers a series of pharmacological effects causing relaxation of both the penile arteries and the cavernous smooth muscle, resulting in increased penile blood flow. Interestingly, previous smaller studies of caffeinated drinks did not find this association.

It is important to remember that erectile dysfunction has a multi-factorial origin. Often there is some organic component, but it is almost always associated with some psychological factors. Thus, this study cannot tell us how to treat erectile dysfunction, but rather that caffeinated drinks, especially coffee, lower the odds of the development of erectile dysfunction.