Most of us have heard the phrase “he’s a grower, not a shower,” referring to someone whose penis appears much bigger when erect than flaccid. But while this is a common phrase, is being a “grower, not a shower” really a thing? It may surprise you to learn that there have been actual studies devoted to figuring this out.
First, keep in mind that all penises are bigger when erect. So in that sense, everyone with a penis is a “grower.” But when we talk about "growers v. showers," we're talking about the difference between the size of someone's flaccid penis and the size of someone's erect penis. If there's a big difference, they're a grower. If there's a small difference, they're a shower.
To find out the reality of growers v. showers, researchers conducted a study published in the International Journal of Impotence Research titled, “Grower or shower? Predictors of change in penile length from the flaccid to erect state.” Researchers measured the flaccid and “peak erection” penises of 274 men who were treated for erectile dysfunction. They found that the median change in penis length from flaccid to erect was 4.0 centimeters, or about 1.6 inches. Men whose penises expanded at least 4.0 centimeters in length during an erection were deemed “growers,” while men whose penises expanded less than 4.0 centimeters were classified as “showers.”
The study found that just over one-quarter (26%) of men fit the “grower” definition, with an average growth of 5.3 centimeters (or about 2.1 inches) from flaccid to erect. 74% were “showers,” with an average growth of 3.1 centimeters (about 1.2 inches). The researchers found that race, smoking history, co-morbidities, and the size of the men’s flaccid penises did not play a factor in determining the growers vs. the showers. However, the growers were a little younger, with an average age of 47.5 years, compared to the showers’ average age of 55.9 years.
Other research has suggested that the elasticity and proportion of collagen fibers in a person’s penis tissue may determine if they’re a grower or a shower. These differences are partially determined by genetics, and partially determined by health and age. That means someone might go from being a "grower" to being a "shower" as they get older.