Men's Core LabMen's Core LabFree app
ED and erections

What is erectile dysfunction? How erections work, 4 types of causes and age

Updated 5 references7 min readMen's Core Lab editors

The studies and sources we used are listed at the end. Not reviewed by a doctor. Editorial policy

ED is not only about having no erection at all. Erections that are not firm enough, or that fade partway through, count too, and about half of men aged 40 to 70 reported some degree of it in a large US study. Here is how erections work, the main causes and how age fits in.

Key points

Erectile dysfunction (ED) means being repeatedly unable to get or keep an erection firm enough for satisfying sex. Its causes fall into four groups: psychological, physical (blood vessels, nerves, hormones), mixed and medication-related. In the Massachusetts Male Aging Study, 52% of men aged 40 to 70 reported some degree of ED, and ED can be an early sign of heart or blood vessel disease.

Contents
  1. What ED means
  2. How erections work
  3. 4 types of causes
  4. How common is ED?
  5. ED as a sign of other illness
  6. Options for ED
  7. When to see a doctor
  8. FAQ
  9. References
  10. Keep reading

What ED means

ED stands for erectile dysfunction. It is usually described as being unable, again and again, to get or keep an erection firm enough to have satisfying sex. It is not only about having no erection at all. It also includes:

  • getting an erection, but not one hard enough for penetration
  • losing firmness partway through (losing an erection during sex)
  • erections that work some times and not others

How erections work

An erection happens when the brain, nerves, blood vessels and muscles work in sequence.

  1. Sexual stimulation sends signals from the brain along the nerves to the penis.
  2. In the spongy tissue inside the penis (the corpora cavernosa), blood vessels relax and blood flows in.
  3. The swollen tissue presses on the veins, so blood cannot drain away easily and the penis stays firm. The pelvic floor muscles around the base of the penis are also thought to play a part.

If any step in this chain does not work well, ED can result.

4 types of causes

Psychological

Nerves, anxiety, stress, depression or relationship problems. If you still get morning erections but things do not work during sex, psychological factors may be involved.

Physical

Changes in the body: blood vessel changes from high blood pressure, diabetes or high cholesterol; nerve damage from surgery or spinal conditions; or low male hormone (testosterone). Most ED that becomes more common with age is thought to involve blood vessel changes.

Mixed

Both mind and body are involved. A common pattern: a physical cause makes erections harder, then worry about "failing again" adds to it.

Medication-related

Some medicines for blood pressure, depression or the prostate can cause ED. Do not stop a medicine on your own; talk to the doctor who prescribed it.

How common is ED?

ED in men aged 40 to 70Massachusetts Male Aging Study1994J Urol
1,290men aged 40–70
52%some degree of ED
5% → 15%complete ED, age 40 vs 70
Found
ED was common and became more so with age; complete ED rose about threefold between 40 and 70
Caveat
Based on questionnaires in one US area in the late 1980s, not on examinations

ED is not only an older man's problem: younger men get it too.

ED as a sign of other illness

ED and later heart and blood vessel diseaseThompson et al.2005JAMA
9,457men aged 55+
~7 yearsfollow-up
25%higher risk
Found
Men who developed ED had about a 25% higher risk of later heart or blood vessel disease than men who did not
Caveat
The men were taking part in a prostate cancer prevention trial; it does not mean ED causes heart disease

The arteries in the penis are narrower than those of the heart, so hardening of the arteries is thought to show up there first. If you notice ED, take it as a reason to have your blood pressure, blood sugar and cholesterol checked.

Options for ED

There are medical options and lifestyle changes you can work on yourself.

What a doctor can discuss

  • Tablets: medicines that help erections (PDE5 inhibitors) are commonly used. They are not safe for everyone, depending on your health and other medicines, so a doctor needs to check first.
  • Other methods: vacuum devices, injections into the penis, or surgery, chosen with your doctor according to the cause.
  • Treating the underlying condition: diabetes, high blood pressure or low hormones are treated alongside.

What you can work on yourself

  • Pelvic floor training: in a randomized trial of 55 men (Dorey et al., 2004), 40% of the group that trained for 3 months had erectile function scores back in the normal range.
  • Aerobic exercise: in a review of studies (Gerbild et al., 2018), many studies used moderate to vigorous exercise for 40 minutes, 4 times a week, for about 6 months.
  • Weight, diet and not smoking: in a trial of 110 men with obesity (Esposito et al., 2004), 31% of the group that changed their lifestyle for 2 years had erectile function scores in the normal range.

When to see a doctor

See a urologist, men's health clinic or your doctor if ED continues, started suddenly, if morning erections have almost stopped, if you have diabetes, high blood pressure or high cholesterol, or if you have chest pain or shortness of breath.

FAQ

What does ED mean?

ED (erectile dysfunction) means being unable, again and again, to get or keep an erection firm enough for satisfying sex. It is not only about having no erection at all: erections that are not hard enough, or that fade partway through, count too.

At what age does ED become common?

It becomes more common with age, but younger men get it too. In the Massachusetts Male Aging Study of 1,290 men aged 40 to 70, 52% reported some degree of ED, and complete ED rose from about 5% at age 40 to about 15% at 70. In younger men, nerves and tiredness often play a part, but a physical condition can also be behind it.

Can ED be a sign of another health problem?

It can. A study that followed about 9,000 US men aged 55 and over for 7 years (Thompson et al., 2005) reported that men who developed ED had about a 25% higher risk of later heart or blood vessel disease. The arteries in the penis are narrow, so hardening of the arteries may show up there first.

Can exercise or lifestyle changes help with ED?

Aerobic exercise (around 160 minutes a week), pelvic floor training, and diet plus exercise to lose weight have all been studied. In a randomized trial of 110 men with obesity (Esposito et al., 2004), about a third of the lifestyle group had erectile function scores in the normal range after 2 years. ED can also be an early sign of heart or blood vessel disease, so have a doctor check the cause first.

References

  1. Feldman HA, et al. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol. 1994;151(1):54-61. pubmed.ncbi.nlm.nih.gov/8254833/
  2. Thompson IM, et al. Erectile dysfunction and subsequent cardiovascular disease. JAMA. 2005;294(23):2996-3002. pubmed.ncbi.nlm.nih.gov/16414947/
  3. Dorey G, et al. Randomised controlled trial of pelvic floor muscle exercises and manometric biofeedback for erectile dysfunction. Br J Gen Pract. 2004;54(508):819-825. pmc.ncbi.nlm.nih.gov/articles/PMC1324914/
  4. Gerbild H, et al. Physical Activity to Improve Erectile Function: A Systematic Review of Intervention Studies. Sex Med. 2018;6(2):75-89. doaj.org/article/91eb296258654277ba5cb0268ced6754
  5. Esposito K, et al. Effect of lifestyle changes on erectile dysfunction in obese men: a randomized controlled trial. JAMA. 2004;291(24):2978-2984. search.pedro.org.au/search-results/record-detail/11354

Keep reading