By: Chris Iliades, MD, Everyday Health.

Many men stay closed-mouth about their health, be it an illness or weight gain or wacky sexual problem. You can probably chalk it up to a disconnect with doctors (a recent report from the U.S. Centers for Disease Control and Prevention found that men are 80 per cent less likely than women to use a source of health care regularly) or the idea that they can “tough out” any problem.

And this pension for privacy often extends to the bedroom too — many men stay mum when they have a question about their sexual health (“Does size really matter?”; “Am I at risk for erectile dysfunction?”).

Here’s the naked truth about the male anatomy:

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  • Average Penis Size Isn't 9 Inches

    The average size of an erect penis is about 5 to 7 inches; when it’s not erect, it measures just 1 to 4 inches. So what’s the answer to that age-old question — does size really matter? It depends on whom you’re asking. In a study of more than 52,000 men and women, which was published in the journal Psychology of Men and Masculinity, 45 per cent of men revealed that they were unsatisfied with their penis size. However, 84 per cent of women said they were completely content with the size of their partner.

  • Marathon Sex Is Not the Norm

    It’s time to cut the average guy some slack: Having sex that lasts for hours is not typical. In fact, a survey of certified sex therapists in Canada and the United States, done by Penn State University, found that the most desirable duration from penetration to orgasm is 7 to 13 minutes.

  • Guys Fake Orgasms, Too

    Do men ever bluff in the bedroom? Sure they do. A recent study in the Journal of Sexual Research found that <a href="http://www.everydayhealth.com/sexual-health/do-men-fake-orgasms.aspx">67 per cent of women and 28 per cent of men admitted to faking an orgasm</a> — at least once. Reasons ranged from wanting to please their partner to hoping to conceal premature ejaculation to just wanting the lovemaking to be over with already. How’d they fake it? These men reported using a combination of moaning, vocalizations, and changes in physical movements.

  • You Can Break Your Penis

    It's not easy to do — but if you’re in the middle of over-the-top, acrobatic sex (especially if the woman’s on top), you could be at risk for a penile fracture. A fracture of the penis occurs when one of the membranes surrounding a blood-filled penile chamber breaks (perhaps because a woman brings her body weight down at the wrong angle, bending the penis in such a way that causes a painful rupture). Needless to say, this causes rapid deflation of an erection and pain. And if a fractured penis is not properly treated (by calling your doctor or going to an emergency room), it can actually cause scarring, deformity, or erectile dysfunction.

  • Circumcised Or Uncircumcised? Depends Where You Live

    In the United States, the majority of males are circumcised as babies — but that’s not the case around the globe. According to the World Health Organization, only about 30 per cent of penises worldwide are circumcised. Even in America, the percentage is falling (the CDC recently reported that circumcision is slightly less common than it was a decade ago, dropping to about 57 per cent from 63 per cent). And the American Academy of Pediatrics no longer recommends routine circumcision, citing health reasons.

  • Bikes Can Be Bad for Your Sex Life

    Here’s a little-known fact: Riding a bicycle with a skinny seat can put enough pressure on a male’s anatomy that it causes erectile dysfunction. Those narrow seats may make men look like road racers, but all their body weight is riding right on the part of the pelvis that supplies blood vessels and nerves to the penis. The solution is to opt for a fat, padded seat that supports the bottom. It may not look cool, but your sex life will thank you.

  • Smoking Can Cause Erectile Dysfunction

    Just in case you need one more reason to kick your cigarette habit, consider this: Smoking has been shown to double the risk for erectile dysfunction. That's because nicotine causes blood vessels to constrict, decreasing blood flow to the penis — which can be deadly for an erection. Other studies have shown that smoking decreases the number of sperm in a man's semen and that non-smokers (who tend to be healthier overall) have a better sex life.

  • It's Not Just Down Below: Men's Brains Are Wired Differently, Too

    Research has proven what most of us have thought all along: A man's brain works differently than a woman's. Males start to fantasize about sex by age 11, and according to recent research published in the Journal of Sex Research, most men think about sex about 19 times per day (dispelling that whole “every seven seconds” rumour). Women, on the other hand, think sexy thoughts about 10 times a day.

  • Male Anatomy Has a Long Shelf Life

    Women experience a rapid loss of fertility during menopause, but men go on making sperm for decades. And while erectile dysfunction rates do increase with age (4 per cent of men in their fifties are affected by ED, 17 per cent in their 60s, and 47 per cent of those over 75, according to the National Institutes of Health), many older men are still able to get erections, enjoy sex, and even father children.

Average Penis Size Isn't 9 Inches:
The average size of an erect penis is about 5 to 7 inches; when it’s not erect, it measures just 1 to 4 inches. So what’s the answer to that age-old question — does size really matter?

It depends on whom you’re asking. In a study of more than 52,000 men and women, which was published in the journal Psychology of Men and Masculinity, 45 per cent of men revealed that they were unsatisfied with their penis size. However, 84 per cent of women said they were completely content with the size of their partner.

But about six out of every 1,000 men really do face a big problem in the bedroom: Their penis is so small that it can lead to erection problems (a condition known as micropenis).

Marathon Sex Is Not the Norm:
It’s time to cut the average guy some slack: Having sex that lasts for hours is not typical. In fact, a survey of certified sex therapists in Canada and the United States, done by Penn State University, found that the most desirable duration from penetration to orgasm is 7 to 13 minutes.

Guys Fake Orgasms, Too:
Do men ever bluff in the bedroom? Sure they do. A recent study in the Journal of Sexual Research found that 67 per cent of women and 28 per cent of men admitted to faking an orgasm — at least once. Reasons ranged from wanting to please their partner to hoping to conceal premature ejaculation to just wanting the lovemaking to be over with already. How’d they fake it? These men reported using a combination of moaning, vocalizations, and changes in physical movements.

You Can Break Your Penis:
It's not easy to do — but if you’re in the middle of over-the-top, acrobatic sex (especially if the woman’s on top), you could be at risk for a penile fracture.

A fracture of the penis occurs when one of the membranes surrounding a blood-filled penile chamber breaks (perhaps because a woman brings her body weight down at the wrong angle, bending the penis in such a way that causes a painful rupture). Needless to say, this causes rapid deflation of an erection and pain. And if a fractured penis is not properly treated (by calling your doctor or going to an emergency room), it can actually cause scarring, deformity, or erectile dysfunction.

Circumcised Or Uncircumcised? Depends Where You Live:
In the United States, the majority of males are circumcised as babies — but that’s not the case around the globe. According to the World Health Organization, only about 30 per cent of penises worldwide are circumcised.

Even in America, the percentage is falling (the CDC recently reported that circumcision is slightly less common than it was a decade ago, dropping to about 57 per cent from 63 per cent). And the American Academy of Pediatrics no longer recommends routine circumcision, citing health reasons.

Bikes Can Be Bad for Your Sex Life:
Here’s a little-known fact: Riding a bicycle with a skinny seat can put enough pressure on a male’s anatomy that it causes erectile dysfunction. Those narrow seats may make men look like road racers, but all their body weight is riding right on the part of the pelvis that supplies blood vessels and nerves to the penis.

The solution is to opt for a fat, padded seat that supports the bottom. It may not look cool, but your sex life will thank you.

Smoking Can Cause Erectile Dysfunction:
Just in case you need one more reason to kick your cigarette habit, consider this: Smoking has been shown to double the risk for erectile dysfunction. That's because nicotine causes blood vessels to constrict, decreasing blood flow to the penis — which can be deadly for an erection. Other studies have shown that smoking decreases the number of sperm in a man's semen and that non-smokers (who tend to be healthier overall) have a better sex life.

It's Not Just Down Below: Men's Brains Are Wired Differently, Too:
Research has proven what most of us have thought all along: A man's brain works differently than a woman's. Males start to fantasize about sex by age 11, and according to recent research published in the Journal of Sex Research, most men think about sex about 19 times per day (dispelling that whole “every seven seconds” rumour). Women, on the other hand, think sexy thoughts about 10 times a day.

Male Anatomy Has a Long Shelf Life:
Women experience a rapid loss of fertility during menopause, but men go on making sperm for decades. And while erectile dysfunction rates do increase with age (4 per cent of men in their fifties are affected by ED, 17 per cent in their 60s, and 47 per cent of those over 75, according to the National Institutes of Health), many older men are still able to get erections, enjoy sex, and even father children.