Diabetes and ED: why they overlap and what managing diabetes changes

In short: diabetes and erectile dysfunction (ED) often go together. The National Institutes of Health (NIH) says high blood glucose can damage the blood vessels and nerves that erections depend on, that more than half of men with diabetes will get ED, and that men with diabetes can develop it 10 to 15 years earlier than men without it. The same sources say good diabetes management may help prevent and treat that kind of ED. This guide covers why the two overlap, how often, how type 1 and type 2 compare, what the trials show about managing diabetes and about ED medicines, and when to bring it up with a clinician.

Does diabetes cause erectile dysfunction?

Diabetes is one of the most common conditions that can lead to ED. The NIH’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) lists diabetes first among the most common diseases and conditions that can lead to ED (NIDDK, Symptoms & Causes of ED), and its diabetes guidance says men with diabetes are “more than 3 times more likely to develop ED” than men without it (NIDDK, Diabetes, Sexual, & Bladder Problems). That is a statement about risk across many men. It does not mean diabetes is the reason for any one man’s ED, because age, blood pressure, medicines, mood and other conditions can all play a part. Our guide to what ED can signal about your health covers the wider picture, and our page on chronic conditions and ED covers kidney disease, obesity and other long-term conditions that often sit alongside diabetes.

Why does diabetes affect erections?

NIDDK explains that blood vessels and nerves “can be damaged by the effects of high blood glucose,” and that this damage can lead to sexual problems. It adds that changes in blood vessels, nerves, hormones and emotional health during diabetes can all make sex more difficult (NIDDK, Diabetes, Sexual, & Bladder Problems). Researchers in the Look AHEAD trial describe the mechanics in more detail: men with diabetes may have impaired nerve-driven and blood-vessel-driven relaxation of the smooth muscle in erectile tissue, along with changes in how the body makes nitric oxide (Wing et al., J Sex Med 2010). Our page on nerve conditions and ED covers the nerve side, and how ED medications work walks through the nitric oxide chain.

How often do diabetes and ED overlap?

Very often, though the exact number depends on who is studied and how ED is measured. A 2017 review that pooled 145 studies of 88,577 men with diabetes (average age about 56) found ED in 52.5% of them overall. In the eight studies that also included healthy controls, men with diabetes had about 3.6 times the odds of ED (Kouidrat et al., Diabet Med 2017). The American Urological Association (AUA) guideline calls ED “one of the most common complications of diabetes mellitus” and says its prevalence ranges from 20% to 85% depending on how severe and how long-standing the diabetes is. It also cites the Massachusetts Male Aging Study, which reported ED in 28% of men with diabetes against 10% of men without it, after adjusting for age (AUA Erectile Dysfunction Guideline). These are averages from observational research, not a prediction for any one man.

Does type 1 differ from type 2?

In the 2017 pooled review, ED was reported in 37.5% of men with type 1 diabetes and 66.3% of men with type 2 (Kouidrat et al., Diabet Med 2017). Those figures come from different groups of studies, and the abstract does not show that the type of diabetes itself explains the gap, so they are best read as a rough guide. NIDDK’s account of blood vessel and nerve damage is written for diabetes in general, and the AUA guideline says a higher relative risk of ED has been linked with a longer duration of diabetes (AUA Erectile Dysfunction Guideline). The research on what helps differs by type, and the next sections take each in turn.

Can ED be an early sign of diabetes?

It can be, which is one reason it is worth raising. The AUA guideline says that “in some cases, ED may be a manifestation of previously undiagnosed diabetes mellitus,” and that this highlights the importance of screening men with ED for diabetes-related risk factors (AUA Erectile Dysfunction Guideline). NIDDK also says changes in sexual function may be a sign of diabetes (NIDDK, Diabetes, Sexual, & Bladder Problems). ED on its own does not mean you have diabetes, since it has many possible causes. It is a reason for a checkup, which our guide to when to see a doctor about ED walks through.

What makes ED more likely in men with diabetes?

NIDDK lists the factors that make sexual problems more likely in people with diabetes. Several of them are things a care plan can address (NIDDK, Diabetes, Sexual, & Bladder Problems):

• high blood glucose that is not well controlled
• nerve damage (neuropathy)
• high blood pressure or high cholesterol that is not treated
• overweight or obesity
• not being physically active
• certain medicines
• drinking too much alcohol
• smoking

In the type 1 trial below, age, peripheral neuropathy and urinary symptoms were also linked to higher risk (Wessells et al., J Urol 2011). Several of these overlap with heart risk, which is why our page on heart disease and ED treatment is worth reading alongside this one, and our guide to lifestyle and ED and the page on smoking and ED cover the habits on the list.

Is ED caused by diabetes reversible?

No source promises that ED linked to diabetes goes away, but the evidence says managing diabetes can change the odds. NIDDK says good diabetes management “may help prevent and treat ED caused by nerve damage and circulation problems,” and that a doctor can treat ED with medicine or a change in the diabetes care plan (NIDDK, Diabetes, Sexual, & Bladder Problems). The two trials below show what that looks like in practice, and also where it falls short.

Type 1: tighter glucose control. The Diabetes Control and Complications Trial randomly assigned 761 men with type 1 diabetes to intensive or conventional glucose control, and 571 of them were assessed for ED about 10 years after the trial ended. In the group that already had early eye or kidney changes at the start, ED was less common after intensive control (12.8% against 30.8%). In the group without those changes, the difference was small and not statistically significant (17% against 20.3%). In both groups, a higher average HbA1c, a measure of long-term blood glucose, went with a higher risk of ED (Wessells et al., J Urol 2011).

Type 2: weight loss and activity. In the Look AHEAD trial, 306 overweight or obese men with type 2 diabetes (average age about 60) were followed for a year. Men in the lifestyle program lost about 9.9% of their body weight against 0.6% in the comparison group. Fewer of them saw their erectile function get worse (8% against 20%), but the share whose function improved was about the same in both groups. The authors concluded that weight loss “may help to preserve function or prevent worsening,” with little evidence it actually improved erectile function over one year, and they noted that the changes diabetes causes in erectile tissue “could limit the reversibility” of this kind of ED (Wing et al., J Sex Med 2010).

So the honest answer is that managing diabetes is worth doing for erections as well as everything else, that it seems to help most by protecting function over time, and that it does not guarantee improvement on its own. NIDDK notes that a doctor can also treat ED with medicine.

Do ED medicines work for men with diabetes?

Yes. The FDA-approved labels for vardenafil, sildenafil and tadalafil each include a trial run only in men with diabetes, and in each one the medicine beat a placebo. The responses were real but not universal, as the table shows. The labels list the exact amounts tested; this page leaves those out, because the choice of medicine and amount belongs to your prescriber.

Sources: vardenafil prescribing information, DailyMed; VIAGRA prescribing information, DailyMed; CIALIS prescribing information, DailyMed.

These trials were run separately, with different designs and measures, so the rows should not be read as a ranking. The AUA guideline says men with ED should be told about FDA-approved oral PDE5 inhibitors, including their benefits and risks, “unless contraindicated” (AUA Erectile Dysfunction Guideline). If you take medicines for blood pressure or the heart, the interaction and safety checks matter; our guide to the safest ED medication covers what the labels say about who should not take each one. If a medicine you have been prescribed is not helping, our page on why sildenafil may not be working covers the common reasons to raise with your prescriber.

What else should men with diabetes know about sex and ED?

Testosterone. NIDDK says men with diabetes, especially older and overweight men, are more likely to have low testosterone, which can play a part in ED, tiredness and low sex drive. It notes that testosterone therapy may have serious risks and may not be safe for all men (NIDDK, Diabetes, Sexual, & Bladder Problems). The AUA guideline says men with ED and testosterone deficiency who are considering a PDE5 inhibitor should be told it may work better combined with testosterone therapy (AUA Erectile Dysfunction Guideline). Our page on ED and low testosterone goes further.

Blood glucose around sex. NIDDK describes sex as a physical activity and suggests checking blood glucose before and after, especially for people who take insulin, because both high and low blood glucose can cause problems during sex (NIDDK, Diabetes, Sexual, & Bladder Problems). Your diabetes care team can tell you what that means for your own plan.

Penile curvature. NIDDK says men with diabetes are more likely to have Peyronie’s disease, in which scar tissue makes the penis curve when erect, and that some men with it also have ED. Our guide to Peyronie’s disease covers it.

The bottom line

Diabetes is one of the most common conditions linked to ED: more than half of men with diabetes get it, through damage to blood vessels and nerves, with hormones and mood also playing a part. The figures are higher in pooled studies of type 2 than type 1, though those numbers are rough. Managing glucose, blood pressure, cholesterol and weight is the part NIDDK points to, and the trials suggest it helps most by protecting erectile function over time rather than guaranteeing improvement. ED medicines beat placebo in trials run only in men with diabetes, and a clinician who knows your full health picture is the right person to decide what fits.

Sources

Every clinical statement on this page traces to a primary or guideline source:

• NIH NIDDK, Diabetes, Sexual, & Bladder Problems (last reviewed June 2018): blood vessel and nerve damage from high blood glucose; ED 10 to 15 years earlier; more than half of men with diabetes and more than 3 times as likely; risk factor list; management may help prevent and treat ED; low testosterone and testosterone therapy risks; Peyronie’s disease; checking blood glucose around sex; seeing a health care professional.
• NIH NIDDK, Symptoms & Causes of Erectile Dysfunction (last reviewed October 2024): diabetes among the most common diseases and conditions that can lead to ED.
• American Urological Association, Erectile Dysfunction Guideline: ED as a common complication of diabetes; 20% to 85% prevalence by severity and duration; higher relative risk with longer duration; Massachusetts Male Aging Study figures; earlier onset; ED as a possible sign of undiagnosed diabetes and screening; PDE5 inhibitors offered unless contraindicated; PDE5 inhibitors with testosterone therapy in men with testosterone deficiency.
• Kouidrat Y, et al. High prevalence of erectile dysfunction in diabetes: a systematic review and meta-analysis of 145 studies (Diabet Med, 2017): 88,577 men; 52.5% overall; 37.5% type 1 and 66.3% type 2; odds ratio 3.62 against healthy controls in the 8 studies that included them.
• Wessells H, et al. Effect of intensive glycemic therapy on erectile function in men with type 1 diabetes (J Urol, 2011): DCCT/EDIC; 761 men randomized, 571 assessed; 12.8% against 30.8% in the secondary cohort and 17% against 20.3% in the primary cohort; HbA1c, age, neuropathy and urinary symptoms as risk factors.
• Wing RR, et al. Effects of weight loss intervention on erectile function in older men with type 2 diabetes in the Look AHEAD trial (J Sex Med, 2010): 306 men followed for 1 year; 9.9% against 0.6% weight loss; 8% against 20% worsening and similar improvement; authors’ conclusion; mechanisms that could limit reversibility.
• Vardenafil hydrochloride tablets prescribing information, DailyMed: section 14.2, trial in 439 men with ED and diabetes.
• VIAGRA (sildenafil citrate) prescribing information, DailyMed: section 14, trial in 268 men with ED attributed to complications of diabetes, and efficacy across subgroups including diabetes.
• CIALIS (tadalafil) prescribing information, DailyMed: section 14, trial in 216 men with type 1 or type 2 diabetes.