Medically reviewed by Kristin Hall, FNP
Written by Our Editorial Team
Last updated 10/22/2020
Worried about erectile dysfunction? You’re not alone. Erectile dysfunction, or ED, is common and can affect men of all ages and backgrounds.
Beyond being surprisingly common, erectile dysfunction can also occur for a variety of different reasons. Below, we’ve listed 18 surprising facts about how and why erectile dysfunction occurs, who it affects, how it can be treated and more.
Most people think of erectile dysfunction as something that mostly affects older men, particularly men in their 50s, 60s, 70s and eighties.
This is only partly true — while ED is more common in older men than in younger men, it can and does affect men of all ages.
According to the Massachusetts Male Aging Study, men in their 40s have a 40 percent chance of having experienced erectile dysfunction at some point, and that occurrence only increases with age.
Although younger men are at a lower risk of developing ED, it’s still fairly common. A study first published in 2013, which used data from more than 400 patients, noted that one patient out of every four seeking treatment for new onset ED was under the age of forty.
In short, although ED is more common in older men than in younger men, it’s not an issue that only affects men after middle age. If you’re under 40 and occasionally have issues with getting and staying hard, you’re definitely not alone.
Erectile dysfunction is relatively common. As many as 30 million American men may be affected by ED.
This makes ED more common in men than left-handedness (about 10 percent to 15 percent of the population in Western countries).
Although most people associate the term “erectile dysfunction” with the inability to get any kind of erection at all, this isn’t technically correct.
Erectile dysfunction is defined as difficulty developing or maintaining an erection firm enough for penetrative sex.
This means that ED could involve getting an erection but failing to maintain it during sex, or just having difficulty getting an erection due to performance anxiety. Many men with ED might find it easy to get an erection in some circumstances, but not always in others.
Some men, for example, might get ED when they’re feeling stressed, but have no issues getting an erection when they’re in the right mood.
Put simply, the term “erectile dysfunction” doesn’t only refer to complete impotence — it actually covers a spectrum of different problems related to erections and sexual performance.
It’s normal and quite common to sometimes have trouble getting an erection, especially if you’re tired, intoxicated, stressed or just not in the mood for sex.
If this happens to you, it doesn't necessarily mean that you should feel concerned. ED generally only becomes a problem when it starts to affect your self-confidence, makes you feel anxious or stressed about sex or harms your relationship.
Ever wonder why you often wake up with an erection? Morning wood, as it’s commonly known, is an extremely common phenomenon and an excellent overall indicator of sexual health.
Morning wood is the result of nocturnal penile tumescence, or spontaneous erections that can happen while you sleep. On average, a healthy man will get three to five erections per night of sleep, with each lasting for about half an hour.
Nighttime erections appear to occur during the rapid eye movement (REM) phase of the sleep cycle, which is when you’re most likely to dream vividly.
There’s nothing wrong with getting erections at night, or waking up with morning wood. In fact, frequently waking up without an erection could signal an underlying health issue that’s causing physical ED.
While most of us associate erections with adolescence and adulthood, erections actually start in the early years of every male’s life.
In fact, there’s some data out there that indicates erections and other signs of sexuality can even occur in utero.
Contrary to popular belief and the sales pitches of countless “strengthen your penis” products, the penis is not a muscle and probably won’t respond to any type of training designed to boost your penile strength.
With this said, there are some exercises for the pelvic floor muscles that might help to enhance your sexual performance.
The penis is made up of sponge-like chambers called the corpora cavernosa, which, when you feel aroused, gradually fill up with blood. As the corpora cavernosa fill with blood, the increase in pressure prevents blood from flowing away, giving you an erection.
This is why healthy blood flow is so essential for erectile health. The easier it is for blood to flow into the corpora cavernosa, the easier you’ll find it to get an erection when you’re aroused.
At one point or another, just about every man has worried about how their penis size compares to the average.
While there’s no precise average penis size for men, several studies have attempted to answer this question, with most showing that the average erect penis size is somewhere between five and six inches in length.
A 2014 study published in the , which sampled 1,661 men, reached an average length of 14.15cm, or about 5.6 inches. With this said, this study relied on the men to measure themselves, meaning the data may not be perfectly accurate.
A separate review published in , which used data from more than 15,000 men, reached a slightly lower average of 13.24cm, or about 5.2 inches.
Simply put, the average guy isn’t porn star-big. Plus, as we covered in our more detailed guide to average penis size, most women don’t find penis size all that important anyway.
While the penis doesn’t contain any bones and thus can’t fracture like your arm or leg, it’s still possible to “break” your penis.
If your penis is twisted or bends too harshly, it’s possible for the corpora cavernosa to burst and cause blood to flow into the other tissue of the penis. This can lead to serious pain and swelling of the penis.
Reports of “broken” penises are fairly rare, although they are known to happen.
Repeated injuries to the penis may result in the development of scar tissue, which is believed to contribute to a condition called Peyronie's disease.
You might have heard of penises described either as growers (smaller penises that get bigger when erect) or showers (penises that are already reasonably big when flacid and don’t enlarge all that much when erect).
Surprisingly, it turns out the “grower” vs. “shower” contrast may actually have some real science behind it.
Specifically, a 1988 study found that penises that were smaller when flaccid had a greater size increase when erect than larger ones.
It also found that the difference in penis length is smaller when erect (a difference of 0.67 inches) than when flaccid (1.2 inches).
A more recent study from 2018 observed 274 patients via penile duplex Doppler ultrasound and found that there are, in fact, growers and showers. Seventy-four percent of patients were “showers,” while 26 percent were showers.
However, it’s important to note that these studies are small, and more widespread research must be conducted before we can definitively say if the rumors are true.
Although most people associate male orgasm and ejaculation with erections, you don’t actually need to be erect to have an orgasm.
In fact, many men with ED can orgasm without being erect or using medications like Viagra® to treat their ED.
Ever feel anxious before sex? Feeling anxious about your sexual performance can make it far more difficult to get and maintain an erection, even if you’re already excited, totally in the mood and ready to go.
Commonly known as sexual performance anxiety, this form of anxiety tends to occur when you feel concerned about your sexual performance, worried about how you look or just stressed in general.
While there isn’t a huge amount of research into performance anxiety and sex, a 2005 study of 157 men and 186 women found that it’s one of several common factors closely linked to sexual dysfunction in both men and women.
In a 2019 review of existing literature on sexual performance anxiety (from 2000 to 2018), researchers found that sexual performance anxiety may affect as many as 25 percent of men.
Luckily, sexual performance anxiety is sometimes treatable, either through the use of ED medications like sildenafil (generic Viagra), or through things like cognitive behavioral therapy, mindfulness meditation, etc.
While erectile dysfunction itself isn’t a dangerous health condition, it can often be a sign that you may have an underlying health issue.
Erectile dysfunction is common in men with cardiovascular health conditions. For example ED is strongly linked with heart disease, with several studies indicating that men who have ED tend to have an elevated risk of heart disease.
ED is also closely associated with type 2 diabetes, which can cause damage to the nerves and blood vessels that supply the tissue of the penis.
Now, this doesn’t necessarily mean that you’re unhealthy if you occasionally find it difficult to get and stay hard during sex. However, if you find it difficult to get an erection at all, even when you feel relaxed and comfortable, it might be a sign that something isn’t right.
In either case, it’s best to see your healthcare provider. A simple medical exam can often help you to identify the root cause of erectile dysfunction, making it easier to improve your sexual performance and your overall health.
Lifestyle choices like drinking alcohol frequently, smoking cigarettes or using illicit drugs can all contribute to erectile dysfunction, as well as a range of other sexual performance issues.
Beyond the numerous other health risks associated with cigarettes, smoking can constrict your blood vessels, making it harder for blood to flow to the penis. In a 2015 review of smoking and erectile dysfunction, researchers found that smokers have an elevated risk of developing ED.
Likewise, excessive consumption of alcohol is closely linked to sexual dysfunction, with a study from 2007 indicating that 72 percent of alcohol dependent male participants had one or more sexual dysfunctions, such as erectile dysfunction, low sexual desire or premature ejaculation.
Think of medication for treating ED and you probably think of Viagra — the ultra-popular “little blue pill” that in the 1990s came onto the market.
While Viagra is the most well-known treatment for erectile dysfunction, it’s definitely not the only medication available for improving sexual performance in men.
Other drugs, such as Cialis® (which contains tadalafil, a longer-lasting medication), Levitra® (which contains vardenafil) and Stendra® (the newest ED medication on the market) also treat ED, often with longer-lasting effects and fewer side effects than the original little blue pill.
While Viagra is designed to last for about four hours, other ED medications can make it easier to get an erection for significantly longer.
Cialis, known as the “weekend pill,” is the longest lasting of the ED medications. It contains an active ingredient called tadalafil, which lasts for up to 36 hours. This means that if you take one tablet on a Saturday, it will continue working until well into the night on Sunday.
Erectile dysfunction can be physical or psychological. When it’s physical, factors like high blood pressure or heart disease are often the culprits. However, some cases of psychological ED may be caused by watching too much porn.
This phenomenon, referred to as porn-induced ED, hasn’t been studied much. However, there’s some scientific evidence linking porn usage sexual dysfunction.
Does this mean that you should cut porn out of your life completely for better erections? For the average guy, probably not.
However, if you’ve been watching porn more frequently recently and find it harder than normal to get an erection, this could be worth discussing with a healthcare professional.
Erectile dysfunction is extremely common. It’s also highly treatable. Our guide to the treatment options currently available for ED lists everything you need to know about taking action to treat ED and improve your sexual performance.