Diabetes is a serious, long-term health condition that can cause damage throughout the body. In men, it causes particular damage to fertility—the ability to make a woman pregnant. The ultimate cause of this is high blood glucose levels.

Sexual and fertility problems in men often have a large psychological impact. This article will describe those problems and how they occur. It will also discuss how they’re treated.

The good news is that in many cases the damage done to male fertility by type 2 diabetes can be prevented, because type 2 diabetes can be prevented or delayed in up to 60% of people by making sustainable changes in daily habits.

This article explains how that’s done and outlines the support that the Life! program offers to achieve it.

High blood sugar and male infertility

Hyperglaecemia (also known as high blood sugar) occurs when there is too much glucose in the bloodstream. Our bodies need blood glucose to provide our cells with nutrients and energy, but the amount of glucose in the bloodstream must be carefully managed. When it is not managed as with hyperglycaemia, it can result in damage to blood vessels and nerves. This decreases the ability of our nerves to send signals and weakens the walls of the blood vessels that bring them oxygen. This damage is called neuropathy. 

Diabetic neuropathy affects the autonomic nervous system (ANS). The ANS is a network of nerves that connects the brain to the rest of the body, controlling vital processes such as breathing, digestion and sexual functions. Diabetes seriously damages the nerves of the ANS, and one of the signs of this damage is sexual dysfunction. Sexual dysfunction is where one or a group of conditions prevents someone from having or enjoying sex.

This explains the importance of managing blood sugar levels to maintain fertility. Well-managed blood glucose levels reduce the risk of erectile dysfunction and increases men’s testosterone levels and sex drive. 

What is type 2 diabetes?

Diabetes affects how the body converts food into energy. When you eat, your body breaks the food down into glucose, which is then released into your bloodstream. As your blood glucose levels rise, your pancreas releases insulin to allow the glucose to enter your cells, where it’s used for energy.

With diabetes, the body either doesn’t produce enough insulin or is unable to use it effectively. This results in high levels of glucose in the bloodstream (hyperglycaemia), which can damage blood vessels and nerves over time. This, as we have seen, leads to serious long-term health complications. Some of these affect male fertility.

There are two main types of diabetes—type 1 and type 2. There is also gestational diabetes which can occur in pregnancy.

Type 1 diabetes is caused by an autoimmune reaction (meaning that the body attacks the cells of the pancreas) resulting in  pancreas being unable  to make insulin. People with type 1 are usually diagnosed in childhood or adolescence and need to take insulin every day for the rest of their lives to live, as currently there’s no cure for it. Around 10% of people who are living with diabetes have type 1.

Around 90% of people with diabetes have type 2. This is where the body cannot use insulin effectively and therefore can’t keep blood glucose levels in a range that doesn’t do damage. Type 2 develops over years and is usually diagnosed in adults. It’s important to have your blood glucose checked if you’re at risk of type 2 diabetes or have any symptoms (however symptoms are rare or with very late diagnosis). Type 2 can in many cases be prevented or delayed by making changes to your lifestyle. 

Risk factors for type 2 diabetes

Many of the risk factors for developing type 2 diabetes apply to both men and women. Some of them can be changed; others cannot.

Modifiable (changeable) risk factors include:

  • an unhealthy diet 
  • being physically inactive
  • being overweight or obese
  • high cholesterol
  • high blood pressure
  • poor sleep patterns
  • smoking.

Non-modifiable (unchangeable) risk factors include:

  • age—the risk of type 2 diabetes increases with age.
  • Ethnicity
  • having a parent or sibling who has (or had) type 2 diabetes.
  • being male

Being overweight or obese, especially if you carry excess fat around the waist, is a risk factor for type 2 diabetes for both men and women. However, research suggests that men are more likely to develop it at a lower relative weight.

How is diabetes diagnosed?

Diagnosis, monitoring and management can help prevent or delay the symptoms and complications of diabetes. It’s diagnosed through blood tests that show if your blood glucose level is outside the optimal range.

If you are diagnosed with diabetes, it’s important to go for regular check-ups and blood glucose monitoring.

Can diabetes affect male fertility?

A research study looking into how common male infertility as a result of diabetes is, found that 51% of its participants had experienced subfertility (being less than normally fertile or having reduced reproductive capacity). The prevalence of infertility among men with type 2 diabetes was 35.1%.

The effects that diabetes can have on male fertility underline the importance of the early detection and treatment of type 2 diabetes. Treatment can help reduce the risk of developing complications associated with the disease. 

Join our free Life! program today and reduce the risk of diabetes-related fertility challenges!

diabetes male fertility

How does diabetes affect male sexual and reproductive health?

Obesity and type 2 diabetes have a close association, and men who live with both conditions may experience reductions in:

  • semen volume
  • total sperm count
  • sperm concentration
  • progressive motility (the type of sperm movement that’s necessary to reach and fertilise eggs)
  • testosterone level.

Male infertility—Erectile dysfunction, Retrograde ejaculation, Sperm quality and count

Diabetes is associated with the following aspects of male infertility.

Erectile dysfunction (ED)

ED is where a man either can’t get an erection or can’t keep one for long enough to have sex. Seventy-five percent of men with diabetes experience ED.

Hyperglycaemia causes erectile dysfunction in the following ways:

  • It reduces nitric oxide, a substance that allows the blood flow to the penis that’s necessary for an erection.
  • The damage that hyperglycaemia causes to blood vessels hinders that blood flow. 
  • The damage that hyperglycaemia causes to nerves leads to decreased arousal. 

It’s not only high blood glucose that causes erectile dysfunction; other conditions associated with diabetes do too. High blood pressure, high cholesterol and the tendency to store fat around the belly are all linked to type 2 and all cause ED. Men with diabetes-related ED are between four and five times more likely to acquire Peyronie’s disease. This deforms the penis, making sex either painful or impossible.

Problems with ejaculation

Diabetes affects ejaculation in several ways. It causes retrograde ejaculation, where diabetic neuropathy results in semen going backwards into the bladder during orgasm instead of out of the penis. This can lead to infertility through a reduction of the amount and quality of semen that does emerge normally. Diabetic neuropathy can also cause retarded ejaculation and inability to ejaculate at all.

Recurrent genital thrush

Thrush is an infection that produces a fungus called candida. Men with diabetes can experience repeated cases of genital thrush. This is because the excess sugar that is excreted in their urine encourages candida to develop and thrive.

Symptoms of genital thrush include:

  • redness or a rash (mainly under the foreskin)
  • itching around the head of the penis
  • a ‘yeasty’ smell
  • a white, lumpy appearance to the skin of the penis
  • soreness during sex.

Decreased Libido

Men with diabetes often have decreased libido (low sex drive). It’s caused by fatigue, stress and the side effects of medication. Men with type 2 diabetes who are overweight have twice the risk of experiencing decreased testosterone. This also lowers the libido. 


Hypogonadism is a condition in which the body doesn’t produce enough testosterone. It is more common in men with type 2 diabetes. The conditions are certainly linked, but at the moment we don’t know exactly how. Older age and obesity may be factors, as both are associated with type 2 diabetes and both decrease testosterone levels. Some studies have suggested that hypogonadism is associated with insulin resistance. 

"I have learned how to cook my favourite meals but in a healthier way. I also changed the way I exercise."

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Diabetes and other areas of men’s health that indirectly affect fertility

Diabetes can lead to problems in other areas of men’s health that indirectly affect fertility. These include.


Diabetic fatigue is much worse than normal tiredness: it’s a severe lack of energy that makes simple tasks very difficult. This can result in anxiety, depression and insomnia, as well as dizziness, inability to concentrate and memory problems. There are several ways in which diabetes can cause fatigue:

  • Hyperglycaemia affects circulation. This means our cells are deprived of oxygen and nutrients, and that causes fatigue. High blood sugar also disrupts sleep.  
  • Diabetic complications such as heart disease and kidney problems can cause fatigue—as can some of the medications used to treat them.

Urological problems

Over 50% of men with diabetes experience urological issues. These include:

  • the sudden, frequent and intense need to urinate
  • inability to control urination
  • urinary tract infections (UTIs). 
  • benign prostatic hyperplasia (BPH)—also called an enlarged prostate. This can block the flow of urine from the bladder and cause urinary tract or kidney problems.

Reversing diabetes-induced male infertility

High blood glucose levels caused by diabetes can harm male reproductive function. Although some studies have reported the benefits of using insulin and other glucose regulators to control high blood glucose levels, more high-quality clinical trials are needed to confirm their positive effects on male reproduction.

To prevent and treat erectile dysfunction, it’s important to make lifestyle changes that can help manage blood glucose levels. These changes include eating a healthy diet, exercising regularly, and quitting smoking. 

Type 1 diabetes’ impact on fertilisation

Type 1 diabetes can harm fertility and reproductive health in both men and women. It can cause hormonal imbalances that can lead to problems with implantation and conception. Diabetes is also linked to lower sperm and embryo quality and DNA damage.

Treatment of diabetes-induced male infertility

All of the symptoms of diabetes-induced male infertility can be avoided or improved by lifestyle changes and, if appropriate, medication and surgery.

For example, treatment for erectile dysfunction can include medicine that increases blood flow to the penis as well as supplementary testosterone. An implant placed inside the penis by surgery is often recommended, as is use of a device that fits over the penis, creating a low-pressure vacuum that causes an erection. 

A growing range of medication is available, including the standard medicine for type 2, metformin.

Metformin helps insulin to work effectively and reduces the amount of the glucose that is stored up inside the liver from being released. 

Other medications increase the amount of insulin that your pancreas makes and help it to work effectively. Medication can reduce the amount of stored glucose that is released from your liver and increases the amount that is removed from your body in urine.

Injectable medications for type 2 diabetes called GLP-1 agonists and GLP-1/GIP agonists stimulate the pancreas to produce insulin and decrease the speed at which your stomach empties. That makes you feel full for longer and decreases your appetite.  

All people who live with type 1 diabetes and some with type 2 need  insulin injections to help to manage blood glucose levels.

It is important to seek medical advice about infertility treatment. Working together with a healthcare professional to decide on the most appropriate treatment options, taking into account your personal circumstances (including, of course, your own thoughts and preferences). They will also provide support and guidance throughout the treatment process.


In this article, we’ve examined the link between high blood glucose levels and male infertility, a challenging condition. We’ve seen that diabetes can affect male fertility, as well as sexual health. 

We’ve also seen that diabetes-induced male infertility can be treated with a combination of medication and lifestyle changes. 

In many cases the symptoms and consequences of type 2 diabetes can be avoided, because the condition itself can be prevented in up to 60% of people through making lifestyle changes. These include eating healthily, increasing your level of activity and reaching and maintaining a healthy weight.

 Eating healthily

A healthy diet includes fresh fruits and vegetables, lean meats and whole grains. Consume less junk food and fewer sugary drinks. If you drink alcohol, try to reduce the amount. 

 Being physically active

Aim to do at least 30 minutes of ‘moderate intensity’ physical activity most days. This could be fast walking, swimming or bike riding. Alternatively, you could choose to do three shorter bursts of activity for 10–15 minutes at a time. 

Maintaining a healthy weight

Reaching and maintaining a healthy weight lowers your blood glucose levels. If you’re overweight, losing just 5% to 7% of your body weight can significantly reduce the risk of type 2 diabetes and heart disease. 

But making healthy lifestyle changes isn’t always easy to do on your own. 

This is where the Life! program can help you.

How the Life! program can help you

Life! is a free healthy lifestyle program that helps you improve your eating habits, increase your physical activity and manage stress. The program is for people who are at risk of type 2 diabetes, heart disease and stroke. (People living with diabetes are not eligible for the program.) You can choose from a group course or our telephone health coaching service.

Life! program will support you to reduce the risk of developing type 2 diabetes.

Life! is run by experienced health professionals, including dietitians and exercise physiologists, who guide and support you to make realistic healthy lifestyle changes that suit your needs. The program includes 7 sessions delivered over a 12-month period.

Since 2007, over 75,000 Victorians have learnt more about living a healthy life with the
Life! program. It is the largest prevention program of its kind in Australia.

Learn more about the Life! program.

You can also check your eligibility for the program by taking a quick online test here.

Life! is funded by the Victorian Government and managed by Diabetes Victoria.

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11 Troubling Symptoms of Diabetes in Men: Don’t Ignore Any LongerDiet vs Disease

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Diabetes – Healthy Male

Diabetes – Mayo Clinic

Diabetes – NHS Choices

Diabetes and Nerve Damage – Centers for Disease Control and Prevention

Diabetes Symptoms in Men: Causes & Signs of Type 2 Diabetes in Men – WebMD
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Erectile dysfunction and diabetes: Take control today – Mayo Clinic

How diabetes causes muscle loss – ScienceDaily

How Much of Your Body Mass Is Actually Muscle? – livestrong
Hyperglycaemia (high blood sugar) – healthdirect

Hypogonadism in Men – Endocrine Society

Muscle Mass Percentage Averages and How to Calculate It – Healthline

NMN Improves Diabetes-Induced Male Infertility, New Study Suggests – Nicotinamide Mononucleotide (NMN): Official Info Source

Obesity and diabetes: Relationship, management, and more – Medical News Today

Penile Curvature (Peyronie’s Disease) – NIDDK – National Institute of Diabetes and Digestive and Kidney Diseases

Peyronie’s Disease and the Diabetic – The Diabetic Friend

Peyronie’s Disease Diabetes Is Common With Diabetic Patients – Peyronie’s Disease

Prostate Enlargement (Benign Prostatic Hyperplasia) – NIDDK – National Institute of Diabetes and Digestive and Kidney Diseases

Reproductive Dysfunctions in Males with Type 2 Diabetes Mellitus: An Updated Review – European Medical Journal

The Most Common Diabetes Symptoms In Men – Blog – HealthifyMe
The relationship between diabetes and muscle mass – Open Access Government

Type 1 Diabetes – Symptoms ADA

Type 2 diabetes symptoms and treatments – Illnesses & conditions – NHS inform
Urologic Complications of Diabetes – American Diabetes Association
What is diabetes – Diabetes Australia


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