A study by Kings College in London found that, no matter how well-endowed men are, they are still vulnerable to experiencing shame about the perceived size of their penis. In fact, penis anxiety doesn’t correlate with penis size at all.

"Quite a few of them have been teased about their size either by an ex-partner or in the showers as an adolescent," said David Veale, lead researcher of the study. "It's an emotional feeling.”

Researchers asked 173 men to complete a questionnaire aimed at evaluating their beliefs about penis size. The questionnaire asked about erectile function, depression, and body image in reference their penises. The research team also had a urologist measure the participants’ actual penis size. The sizes of the studied penises ranged from 2.75 inches to 7 inches flaccid and from 3.93 inches to 7.87 inches erect.

To put that in perspective, a study earlier this year found that the average American man’s penis is about 5.6 inches when erect. So, some of the men in this study were well above average in size.

The study found that only about 35 percent of the men surveyed said they were happy with their penis size. Thirty percent reported dissatisfaction with their size. Penis anxiety was highest among gay, bisexual, and older men. Researchers attributed the prevalence of penis shame among gay and bisexual men to the abundance of opportunities to compare body parts. In older men, the insecurity could stem from fears about physical ability to perform.

According to LiveScience, the men surveyed feared that they would be rejected or end up alone because of their penis size. They also had anxiety about being naked around women and other men. Many of the participants also feared that people would be able to see the shape of their penis even when they have their pants on.

Researchers concluded that the anticipated consequences of a perceived small penis — even in average and above-average sized men — led to measurable feelings of inadequacy and self-consciousness.

Source: Veale D, Eshkevari E. Beliefs about Penis Size: Validation of a Scale for Men Ashamed about Their Penis Size. Journal of Sexual Medicine. 2013.