A reader submitted the following question:

“I wonder, does the penis get any smaller with age? In other words, does the penis shrink as men get older?”

Thanks for this great question! If you try searching Google for the answer, you’ll quickly come across lots of articles saying that this does indeed occur—however, none of those articles actually cite any research to back up their claims. Instead, they rely on the opinions of physicians and other medical experts. That's all well and good, but I always like to have data. So, I did some digging.

The best available data I could find to address your question comes for a review paper published in the British Journal of Urology International, which looked at the results of 20 different studies of penis size that, together, included the measurements of more than 15,000 men’s penises (for more details on this study, see here).

The studies included in this review were conducted in multiple countries, including the USA, Germany, Italy, Egypt, and Nigeria. All participants were aged 17 or older, with some studies including men up to 91 years in age! These men all had their measurements taken by trained professionals, which is preferred to men measuring their own penises, given that guys have a tendency to exaggerate when they measure themselves.

As part of this study, the researchers looked at whether penis size was correlated with age. So what did they find? Nothing. Of the studies that looked at this, most found no association.

Interestingly, there were three studies that did find a link between penis size and age, but it was opposite of what you might expect—being older was linked to having slightly larger measurements.

At least based on this review of the penis size literature, there doesn’t seem to be much to the idea that penis size decreases with age. However, there are some alternative explanations to take into account, especially considering that the goal of this research review wasn’t specifically to look at the link between penis size and age (they were mostly focused on looking at the overall average penis size).

For example, if age was confounded with something else—like body mass index—it’s possible that this could be obscuring the association. Think of it this way: the more abdominal fat guys have, the more it reduces their penile length. To the extent that the younger guys in these studies were more likely to be overweight or obese than the older guys, this could have eliminated any association between age and penis size. In other words, when testing for a link between penis size and aging, there are a lot of other variables you'd want to account for in an attempt to isolate the age effect; unfortunately, however, that wasn't done in this review.

Another possibility is that older men who experienced permanent shrinkage were less likely to want to have their penises measured (or maybe they happened to have more health issues), so perhaps they weren’t included in these studies. In other words, there could potentially be a selection effect at play here.

With all of that said, I should mention that there’s good reason to think that a lot of men will at least perceive penile shrinkage with age due to the development of cardiovascular problems. These problems can make it more difficult to achieve full erections, thereby reducing apparent size.

In short, while a review of the research on penis size doesn’t necessarily support the conventional wisdom that men’s penises shrink as they age, ideally, I'd like to see a little more research that addresses some of the limitations noted above before drawing firm conclusions.

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To learn more about this research, see: Veale, D. et al. (2015). Am I normal? A systematic review and construction of nomograms for flaccis and erect penis length and circumference in up to 15,521 men. BJU International.

Image Source: 123RF.com/nito500

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