Skip navigation! Story from Sex. Yes, "Growers Vs. It may surprise you to learn that there have been actual studies devoted to figuring this out.

Introduction
Is it just genetics?
A leading blog on the science of sex, love, and relationships, written by social psychologist Dr. Justin Lehmiller. So what is the typical change in penis length from flaccid to erect—and just how many men fall into the category of grower versus shower anyway?
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By Sam Blanchard For Mailonline. A world-first study has revealed that the vast majority of men's penises grow by less than 4cm when erect. The research, by scientists at the University of California, Irvine, studied men and found that 74 per cent were 'showers' and had penises that grow by 4cm 1. The remaining 26 per cent, called 'growers' by the researchers, enlarged by an average of 5. Growers in the study had an average erection length of Men over 55 are significantly more likely to be showers, the research adds. This may be due to older males having higher levels of inflammation in their bodies that reduces blood flow and tissue elasticity, preventing their penises from growing when they are turned on, according to the researchers. The scientists hope their findings will help men who have prosthetic penises fitted to be more aware of how their members may grow when erect. Previous studies suggest men with larger penises are more body confident, however, separate findings also imply a male's genital size does not influence a woman's sexual satisfaction. Despite this, research has shown women find men more attractive if they have large sexual organs.
For many men, penis size is important, as it represents their masculinity and virility. Sometimes, the terms grower and shower are used to describe what happens to a penis length as it goes from a flaccid to an erect state. These terms are subjective. However, in a study, researchers suggested a guideline to distinguish growers from showers and considered factors that might determine which category a man belongs to. The study involved men who were being treated for erectile dysfunction ED.