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Type 2 diabetes

Type 2 diabetes is a condition in which your body can’t control the amount of glucose (sugar) in your blood. In type 2 diabetes, your body doesn’t respond to insulin properly, and you may not produce enough. This causes your blood glucose level to become too high.

How type 2 diabetes develops
Type 2 diabetes is a lifelong condition in which the body can't control levels of glucose in the blood

About type 2 diabetes

There are two main types of diabetes: type 1 and type 2. Type 2 diabetes is the most common form. About 3.3 million people in the UK have been diagnosed with diabetes, and of these, more than 9 out of 10 have type 2 diabetes.

Type 2 diabetes is more common among older people, but you can develop it at any age. It’s becoming more common in young adults and children. It’s usually associated with being overweight and not very active.

If you have type 2 diabetes, your body stops reacting to insulin properly, and you may also not produce enough of insulin. Insulin is a hormone (a chemical made by your body) that controls the amount of glucose in your blood. It helps glucose move from your blood into your body tissues – like your muscle cells – when you need a quick form of energy. If your body is not responding to insulin properly, your blood glucose level can become too high.

Symptoms of type 2 diabetes

If you have type 2 diabetes, you may not have any obvious symptoms. Your diabetes may be discovered during a routine medical check-up with your GP.

If you do have symptoms of type 2 diabetes, you may:

  • pass urine more often than usual
  • be constantly thirsty
  • lose weight for no obvious reason
  • be extremely tired
  • have blurred vision
  • have itchy skin around your genitals or get regular genito-urinary infections, such as thrush

If you have any of these symptoms, see your GP.

Diagnosis of type 2 diabetes

Your GP will ask about your symptoms and examine you. They may ask you to have a blood test for glucose. Other tests can include the following.

  • A fasting blood glucose test. You will need to have this test at a time when you haven’t eaten anything for at least eight hours.
  • Glycosylated haemoglobin (HbA1C) test. Your HbA1C level is a measure of how much glucose has been taken up by your red blood cells. It can show if you’ve had high blood glucose levels over a long period of time.
  • An oral glucose tolerance test. This is when your blood glucose is measured before and two hours after you’ve had a high-glucose drink. You’ll only need to have this if initial blood tests haven’t been able to determine whether or not you have diabetes.

If your blood test results suggest that you have type 2 diabetes, your GP may advise you to have repeat tests before confirming your diagnosis.

If you're diagnosed with type 2 diabetes, you may be referred to a specialist diabetes clinic.

Treatment of type 2 diabetes

Treatment for type 2 diabetes is aimed at controlling your blood glucose level. This may be with changes to your lifestyle and if necessary, medicines that your doctor can prescribe.


You can help to control your blood glucose level by making some changes to your diet and trying to be more physically active.

  • Eat a healthy, balanced diet with regular meals, three times a day. Include carbohydrates, such as whole-wheat pasta or potatoes, in each meal and eat at least three portions of oily fish each week. Your GP may refer you to a dietitian, who can advise you about keeping your blood glucose level under control.
  • Aim to do 150 minutes of moderate exercise over a week in sessions of 10 minutes or more. This will help you to stay a healthy weight and control your blood glucose level.


Your doctor may recommend you try medicines if lifestyle changes alone don’t keep your blood glucose level under control. There are many types of diabetes medicines available.

Your doctor will usually begin by offering you a medicine called metformin. Metformin works by reducing the amount of glucose that’s released from your liver into your blood. It also improves the way your muscles use glucose.

If metformin doesn’t help you reach your target blood glucose level, your doctor can prescribe a range of other medicines instead. Sometimes, you’ll need to take more than one of these medicines at a time. These medicines include the following.

  • Insulin secretagogues, such as gliclazide, glipizide and glimepiride. These help your pancreas to produce more insulin.
  • DPP-4 inhibitors, such as sitagliptin, saxagliptin or linagliptin. These help your body to produce insulin when it’s needed.
  • Pioglitazone, which helps to improve how your body responds to insulin.
  • SGLT-2 inhibitors including dapagliflozin, empagliflozin and canagliflozin. These tablets can lower your blood glucose and also help you to lose weight.
  • GLP-1 agonists, such as exenatide or liraglutide. These are given by injection and work by helping your body to make more insulin. They can also help you lose weight.

For more information about medicines for type 2 diabetes, speak to your doctor or diabetes specialist nurse.

Insulin injections

Your doctor may suggest you have insulin injections if lifestyle changes and medicines can’t keep your blood glucose level under control.

You’ll usually need to inject yourself with insulin once or twice a day, using either a small needle or a pen-type syringe with replaceable cartridges. You can be prescribed several different types of insulin. Some work more quickly than others and they act for different lengths of time. Your doctor or nurse will advise you which type is best for you.

If you have insulin injections, your doctor or nurse will suggest that you monitor your blood glucose level with a glucose meter at home. This involves taking a pinprick of blood from your finger and putting a drop on a testing strip. You place the testing strip into the glucose meter, which reads it and shows you the result automatically. Monitoring your blood glucose level will help you understand how to adjust your insulin dose according to how much carbohydrate you eat.

Your 'normal' blood glucose range will be specific to you, but a general guide for adults with type 2 diabetes is:

  • before meals: 4 to 7 mmol/litre
  • two hours after meals: less than 9 mmol/litre

Your doctor, GP or diabetes specialist nurse will show you how to monitor your blood glucose level and tell you how often you need to check it.

Causes of type 2 diabetes

Your risk of developing type 2 diabetes can be increased by several factors. These include:

  • being overweight or obese
  • having a close family member with the condition
  • being of African–Caribbean or South-Asian origin
  • being over 40 – your risk increases with age
  • having high blood pressure or heart disease
  • not exercising regularly
  • smoking
  • if you’re a woman, having polycystic ovary syndrome
  • for women, having previously developed diabetes during pregnancy (gestational diabetes)
  • having a condition such as impaired glucose tolerance or impaired fasting glycaemia – in which your blood glucose level is naturally higher than normal

Complications of type 2 diabetes

If you don’t have good control of your blood glucose level, it may become too high (hyperglycaemia). Mild hyperglycaemia doesn’t usually cause any symptoms. But you may find that you’re thirstier than usual, pass urine more often and feel tired as your blood glucose level continues to rise.

If your blood glucose isn’t controlled properly and stays too high, it can lead to a number of problems over the long term. These include:

  • kidney failure
  • nerve damage, which can cause tingling or burning sensations, or cause you to lose your sense of touch or temperature altogether
  • damage to your vision, which could lead to blindness
  • heart disease
  • stroke
  • foot ulcers – which can eventually lead to foot or lower leg amputation
  • persistent or regular infections, such as skin, chest or urine infections

Very rarely, if you have an infection or become dehydrated, your blood glucose can rise to a dangerously high level. This can lead to a condition called hyperosmolar hyperglycaemic state. If this happens, you may become very dehydrated and lose consciousness. Although the risk of this condition is low, it’s a medical emergency and you’ll need to be treated in hospital.


Your blood glucose level can become too low (hypoglycaemia) if you don't eat enough carbohydrate while taking insulin or particular medicines called sulfonylureas (for example, gliclazide). You’re more likely to develop hypoglycaemia if you are also taking other medicines such as beta-blockers, drink too much alcohol or do more physical activity than usual. Hypoglycaemia can cause you to feel faint, sweaty and confused, and you may feel your heart pounding. You can treat it straight away by eating glucose tablets (or a few sweets or a sugary drink).

You may wish to wear a medical emergency identification bracelet, or similar jewellery, so that people know you have diabetes.

Living with types 2 diabetes

It’s important to try to follow as healthy a lifestyle as you can if you have diabetes. This may help to control your glucose level, and also reduce your risk of developing complications.

  • Eat a healthy, balanced diet and take regular exercise, as recommended by your doctor or diabetes specialist nurse.
  • Only drink alcohol in moderation and stick within the recommended limits.
  • If you smoke, stop. Smoking is unhealthy for everyone, but it's especially important to stop if you have diabetes. Having diabetes increases your risk of developing circulatory problems, heart disease and stroke. Your risk of these conditions is even higher if you smoke and have diabetes too.
  • Aim to maintain a healthy weight.

Find out whether there are any education classes for type 2 diabetes in your community – they’re often run by the local health authority. These classes aim to help you learn how to manage your diabetes and monitor your blood glucose level yourself.

You’ll usually be offered a check-up every three to four months to make sure that your blood glucose level is under control. Your doctor may suggest you have regular blood tests for glycosylated haemoglobin (HbA1C). HbA1C is a measure of how well you’re controlling your blood glucose level. The test involves taking blood from a vein in your arm or sometimes a drop of blood from your finger.

You should also have regular eye examinations, dental check-ups, foot checks, cholesterol tests and blood pressure checks. This will help to diagnose any complications early on so that they can be treated.

Being diagnosed with a long-term medical condition, such as diabetes, can be difficult to come to terms with. It’s important to discuss your feelings with your specialist diabetes nurse or GP as they can talk through any concerns you have. Visit the Diabetes UK website to find your local diabetes support group.

Glycaemic index


Click to open full-size image (1.2MB)

FAQ: Are there any side-effects of using insulin for type 2 diabetes

Insulin can have a number of different side-effects. It’s important to ask your GP or specialist for advice.

If you use insulin injections for diabetes, you may get swelling and bruising on and around the skin where you inject. You may also get a skin rash, but this is rare.

Insulin can cause fat to grow more quickly around the injection site, causing soft lumps to build up under your skin. It’s very important that you change injection sites regularly to prevent these lumps forming.

You usually inject insulin before meals into your upper arm, thighs, buttocks or abdomen (tummy). You should also change the exact spot that you use within the injection site each time.

If you take too much insulin, you can develop hypoglycaemia (low blood glucose). If you get hypoglycaemia, you may:

  • feel hungry
  • feel shaky
  • sweat
  • be tired
  • have blurred vision
  • not be able to concentrate
  • have headaches
  • go pale
  • feel your heart pounding

If this happens, eat or drink something sugary straight away. Then eat something containing long-lasting carbohydrates such as a sandwich, some toast or a piece of fruit. Test your blood glucose level to see if it's returning to normal. Your blood glucose level should start going back to normal within 15 minutes of you eating or drinking something. If it doesn’t and you still have symptoms of hypoglycaemia, call for emergency help immediately.

FAQ: Can I drive if I have type 2 diabetes?

You should be able to continue to drive if you have type 2 diabetes. But you need to contact the Driver and Vehicle Licensing Agency (DVLA) if you take certain medicines or have any diabetes complications.

You must make sure that you can safely control a car at all times. If you take sulfonylureas or insulin, you may be at risk of hypoglycaemia (known as a ‘hypo’).

To reduce your risk of developing hypoglycaemia while driving, you should always:

  • check your blood glucose before you start driving
  • eat a snack before driving if your blood glucose level is 5mmol/litre or less
  • not drive with a blood glucose level of less than 4mmol/litre
  • not drive for more than two hours without checking your blood glucose level
  • keep some kind of carbohydrate, such as sweets and a sugary drink, in your car

If you start to feel unwell while you're driving:

  • pull over and stop somewhere safe
  • take glucose tablets or some other form of fast-acting carbohydrate immediately
  • leave the driver's seat and take the keys out of the ignition to make it clear that you're no longer in charge of the car
  • don't start driving again until your blood glucose level is back to normal – this usually takes about 45 minutes

If you take insulin, you must inform the DVLA, whichever type of vehicle you drive. You must also inform the DVLA if you take sulfonylureas or any other diabetes medicine and you drive a bus, coach or lorry. You don’t need to inform the DVLA about your diabetes if you manage your condition with only lifestyle changes and no medication. But you do need to tell the DVLA if you have a condition associated with your diabetes, such as eye problems or nerve damage to your legs or feet. The DVLA may contact your doctor for more information.

FAQ: What am I aiming for with my day-to-day treatment?

Your aim is to keep as healthy as possible by maintaining a healthy weight, keeping active, following a healthy diet and not smoking. You have a large part to play in the control of your condition, so it's important that you understand and follow your treatment plan.

In the long term, uncontrolled high blood glucose (hyperglycaemia) can affect your health. It can increase your risk of heart disease, stroke, kidney failure, nerve damage and blindness.

It's important to aim for your blood glucose level, blood pressure reading and cholesterol (lipid) level to be as near to normal as possible. This will make you less likely to develop short- or long-term health problems associated with diabetes. Having high blood pressure or high blood cholesterol can increase your risk of developing heart problems or stroke.

Here’s a brief guide of what you should be aiming for.

  • Blood glucose level before meals of 4 to 7mmol/litre. Your GP will advise you on whether or not you can monitor your blood glucose level yourself at home.
  • Blood pressure of 130/80mmHg or below. You should be able to keep your blood pressure well controlled with lifestyle changes and medicines.
  • A stable HbA1c level. You’ll be offered an HbA1c blood test at least every six months. This measures how well you’ve been controlling your blood glucose level over the last two to three months.
  • Total blood cholesterol level of less than 4mmol/litre. Your doctor will suggest ways to keep your cholesterols level under control. You may be prescribed medicines to lower your cholesterol level.

Type 2 diabetes can gradually get worse as time goes on. This means that in future you may need to increase the amount of medication you take. Your doctor may also suggest that you move on to insulin, to keep your condition well controlled.

FAQ: Will type 2 diabetes affect my sex life?

Yes it can, if your blood glucose level gets too high. Over time, high blood glucose levels can damage your nerves and blood vessels. This can affect your sex drive, and if you’re a man, your ability to get an erection.

If your diabetes isn’t managed properly, you’re likely to have higher than normal blood glucose levels. Over time, the high blood glucose levels damage your nerves (neuropathy), blood vessels and tissues. Neuropathy is the most common complication of diabetes. It affects more than half of people aged over 60 with type 2 diabetes.

Early signs of diabetic neuropathy include tingling, pain, numbness or weakness in your feet and hands. As the nerve damage progresses, it can cause erectile dysfunction in men. In women, the nerve damage can cause loss of sensation and affect sexual arousal, and may make sex painful.

You’re more likely to have sexual problems if you’re overweight or have high blood pressure or high cholesterol. Psychological problems such as feeling anxious or stressed can also influence your sex drive and ability to get and keep erections.

If you’re having sexual problems, it’s a good idea to see your GP.


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  • Other helpful websites Other helpful websites


    • Diabetes mellitus. PatientPlus., reviewed 2 July 2013 
    • Type 2 diabetes. Clinical Knowledge Summaries., reviewed April 2015
    • Type 2 diabetes in adults. BMJ Best Practice., reviewed 12 June 2015
    • What is diabetes? Diabetes UK., accessed 16 June 2015
    • Preventing type 2 diabetes: risk identification and interventions for individuals at high risk. NICE Guidelines PH38, July 2012.
    • Insulin. Medscape., reviewed 14 February 2014
    • Nursing patients with endocrine problems. Oxford handbook of adult nursing (online). Oxford Medicine Online., published August 2010
    • Therapy-related issues: endocrine system. Oxford handbook of clinical pharmacy (online). 2nd ed. Oxford Medicine Online., published January 2012
    • Management of type 2 diabetes. PatientPlus., reviewed 11 May 2013
    • Type 2 diabetes mellitus. Medscape., reviewed 21 April 2015
    • Joint Formulary Committee. British National Formulary (online). London: BMJ Group and Pharmaceutical Press., accessed 26 June 2015
    • Oxford handbook of nutrition and dietetics (online). 2nd ed. Oxford Medicine Online., published January 2012
    • Diabetes, diet and exercise. PatientPlus., reviewed 20 April 2011 
    • Management of diabetes. Scottish Intercollegiate Guidelines Network (SIGN), March 2010.
    • Type 2 diabetes: the management of type 2 diabetes. NICE Guidelines CG87, May 2009.
    • Oxford handbook of endocrinology and diabetes (online). 3rd ed. Oxford Medicine Online., published March 2014
    • Insulin regimes. PatientPlus., reviewed 13 January 2014
    • Diabetes mellitus (DM). The Merck Manuals., reviewed June 2014
    • Management of type 1 diabetes. PatientPlus., reviewed 11 October 2012
    • Endocrinology. Oxford handbook of general practice (online). 4th ed. Oxford Medicine Online., published April 2014 
    • Preventing type 2 diabetes: population and community-level interventions. NICE Guidelines. PH35, May 2011.
    • Oxford handbook of geriatric medicine (online). 2nd ed. Oxford Medicine Online., published July 2012 
    • Endocrinology. Oxford handbook of clinical medicine (online). 9th ed. Oxford Medicine Online., published January 2014 
    • Emergency management of hypoglycaemia. PatientPlus., reviewed 6 February 2015
    • Diabetes and driving. Driver and Vehicle Licensing Agency (DVLA)., reviewed 23 June 2015
    • Diabetic neuropathy. BMJ Best Practice., reviewed 11 February 2015
    • Erectile dysfunction. Clinical Knowledge Summaries., reviewed December 2014
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