Health A to Z
Diabetes is a lifelong condition that causes a person's blood sugar (glucose) level to become too high.
The hormone insulin, produced by the pancreas, is responsible for controlling the amount of glucose in the blood.
There are two main types of diabetes:
Typical symptoms of type 1 diabetes are:
The symptoms of type 1 diabetes usually develop very quickly in young people (over a few days or weeks). In adults, the symptoms often take longer to develop (a few months).
Read more about the symptoms of type 1 diabetes.
These symptoms occur because the lack of insulin means that glucose stays in the blood and isn’t used as fuel for energy. Your body tries to reduce blood glucose levels by getting rid of the excess glucose in your urine.
It's very important for diabetes to be diagnosed as soon as possible, because it will get progressively worse if left untreated.
Read about how type 1 diabetes is diagnosed.
Type 1 diabetes is an autoimmune condition, which means your immune system attacks healthy body tissue by mistake. In this case, it attacks the cells in your pancreas.
Your damaged pancreas is then unable to produce insulin. So, glucose cannot be moved out of your bloodstream and into your cells.
Type 1 diabetes is often inherited (runs in families), so the autoimmune reaction may be genetic.
It's not known exactly what triggers the immune system to attack the pancreas, but some researchers have suggested it may be a viral infection.
If you have a close relative – such as a parent, brother or sister – with type 1 diabetes, you have about a 6% chance of also developing the condition. The risk for people who don't have a close relative with type 1 diabetes is just under 0.5%.
Diabetes can't be cured. Treatment aims to keep your blood glucose levels as normal as possible and control your symptoms, to prevent health problems developing later in life.
If you're diagnosed with diabetes, you'll be referred to a diabetes care team for specialist treatment and monitoring.
As your body can't produce insulin, you'll need regular insulin injections to keep your glucose levels normal. There are alternatives to insulin injections, but they're only suitable for a small number of patients.
Read about treating type 1 diabetes.
Diabetes can cause serious long-term health problems. It's the most common cause of vision loss and blindness in people of working age.
Everyone with diabetes aged 12 or over should be invited to have their eyes screened once a year for diabetic retinopathy.
Diabetes is the reason for many cases of kidney failure and lower limb amputation.
Read more about the complications of type 1 diabetes.
If you have type 1 diabetes, you'll need to look after your health very carefully. This means:
Read more about living with type 1 diabetes.
The symptoms of type 1 diabetes can develop very quickly (over a few days or weeks), particularly in children.
In older adults, the symptoms can often take longer to develop (a few months).
However, they should disappear when you start taking insulin and the condition is under control.
The main symptoms of diabetes are:
Vomiting or heavy, deep breathing can also occur at a later stage. This is a dangerous sign and requires immediate admission to hospital for treatment.
See your GP if you think you may have diabetes.
You should seek urgent medical attention if you have diabetes and develop:
If you have diabetes, your blood glucose levels can become very low. This is known as hypoglycaemia (or a "hypo"), and it's triggered when injected insulin in your body moves too much glucose out of your bloodstream.
In most cases, hypoglycaemia occurs as a result of taking too much insulin, although it can also develop if you skip a meal, exercise very vigorously or drink alcohol on an empty stomach.
Symptoms of a "hypo" include:
A hypo can be brought under control simply by eating or drinking something sugary.
If it isn't brought under control, a hypo can cause confusion, slurred speech and eventually unconsciousness.
In this case, an emergency injection of a hormone called glucagon will be needed. Glucagon increases the glucose in your blood.
As people with type 1 diabetes cannot produce any insulin, their blood glucose levels may become very high.
When your blood glucose levels become too high, it's known as hyperglycaemia. The symptoms of hyperglycaemia may come on suddenly and include:
Left untreated, hyperglycaemia can lead to diabetic ketoacidosis. This is a serious condition where the body breaks down fat and muscle as an alternative source of energy. This leads to a build-up of acids in your blood, which can cause vomiting, dehydration, unconsciousness and even death.
Diabetes UK has more information about diabetes symptoms.
It's important for diabetes to be diagnosed early so treatment can be started as soon as possible.
If you experience the symptoms of diabetes, visit your GP as soon as possible. They'll ask about your symptoms and may request blood and urine tests.
Your urine sample will be tested for glucose. Urine doesn't normally contain glucose, but glucose can pass from the kidneys into your urine if you have diabetes.
If your urine contains glucose, a specialised blood test known as glycated haemoglobin (HbA1c) can be used to determine whether you have diabetes.
The glycated haemoglobin (HbA1c) test can be used to diagnose diabetes. It can also be used to show how well diabetes is being controlled.
The HbA1c test gives your average blood glucose level over the previous two to three months. The results can indicate whether the measures you're taking to control your diabetes are working, by meeting agreed personal targets.
If you've been diagnosed with diabetes, it's recommended that you have your HbA1c measured at least twice a year. However, you may need to have your HbA1c measured more frequently if:
The HbA1c test can be carried out at any time of day and doesn't require any special preparation, such as fasting. However, it's less reliable in certain situations, such as during pregnancy.
The advantages associated with the HbA1c test make it the preferred method of assessing how well blood glucose levels are being controlled in a person with diabetes.
HbA1c is also increasingly being used as a diagnostic test for type 2 diabetes, and as a screening test for people at high risk of diabetes.
The majority of children who develop diabetes will have type 1 diabetes.
You'll need to manage your child's condition as part of your daily life, but you'll be introduced to a specialist diabetes care team who can help you to come to terms with any challenges.
Read about diabetes and your child.
If you have type 1 diabetes, you'll probably need insulin injections. Insulin must be injected, because if it were taken as a tablet, it would be broken down in your stomach (like food) and would be unable to enter your bloodstream.
When you're first diagnosed, your diabetes care team will help you with your insulin injections, before showing you how and when to do it yourself. They'll also show you how to store your insulin and dispose of your needles properly.
Insulin injections are usually given by an injection pen, which is also known as an insulin pen or auto-injector. Sometimes, injections are given using a syringe. Most people need two to four injections a day.
Your GP or diabetes nurse may also teach one of your close friends or relatives how to inject the insulin properly.
Insulin pump therapy is an alternative to injecting insulin. An insulin pump is a small device that holds insulin and is about the size of a pack of playing cards.
The pump is attached to you by a long, thin piece of tubing, with a needle at the end, which is inserted under your skin. Most people insert the needle into their stomach, but you could also insert it into your hips, thighs, buttocks or arms.
The pump allows insulin to continuously flow into your bloodstream at a rate you can control. This means you no longer need to give yourself injections, although you'll need to monitor your blood glucose levels very closely to ensure you're receiving the right amount of insulin.
Insulin pump therapy can be used by adults, teenagers and children (with adult supervision) who have type 1 diabetes. However, it may not be suitable for everyone. Your diabetes care team may suggest pump therapy if you have frequent episodes of low blood glucose (hypoglycaemia).
Diabetes UK has more information about insulin.
If you have type 1 diabetes, your GP or diabetes care team will need to take a reading of your blood glucose level about every two to six months.
This will show how stable your glucose levels have been in the recent past and how well your treatment plan is working.
The HbA1c test is used to measure blood glucose levels over the previous two to three months.
HbA1c is a form of haemoglobin, the chemical that carries oxygen in red blood cells, which also has glucose attached to it.
A high HbA1c level means that your blood glucose level has been consistently high over recent weeks, and your diabetes treatment plan may need to be changed.
Your diabetes care team can help you set a target HbA1c level to aim for. This will usually be less than 59mmol/mol (7.5%). However, it can be as low as 48mmol/mol (6.5%) for some people.
Read more about the HbA1c test.
If you have type 1 diabetes, as well as having your blood glucose level checked by a healthcare professional every two to six months, you may be advised to monitor your own blood glucose levels at home.
Even if you have a healthy diet and are taking tablets or using insulin therapy, exercise, illness and stress can affect your blood glucose levels.
Other factors that may affect your blood glucose levels include drinking alcohol, taking other medicines and, for women, hormonal changes during the menstrual cycle.
If blood glucose monitoring is recommended, you should be trained in how to use a blood glucose meter and what you should do if the reading is too high or too low.
Blood glucose meters aren't currently available for free on the NHS but, in some cases, blood monitoring strips may be. Ask a member of your diabetes care team if you're unsure.
Regularly monitoring your blood glucose levels will ensure your blood glucose is as normal and stable as possible.
As your blood glucose level is likely to vary throughout the day, you may need to check it several times a day, depending on the treatment you're taking.
In home testing, blood glucose levels are usually measured by how many millimoles of glucose are in a litre of blood.
A millimole is a measurement used to define the concentration of glucose in your blood. The measurement is expressed as millimoles per litre, or mmol/l for short.
A normal blood glucose level is 4-6 mmol/l before meals (preprandial) and less than 10 mmol/l two hours after meals (postprandial), although this can vary from person to person.
Your diabetes care team can discuss your blood glucose level with you in more detail.
Hyperglycaemia can occur when your blood glucose levels become too high. It can happen for several reasons, such as eating too much, being unwell or not taking enough insulin.
If you develop hyperglycaemia, you may need to adjust your diet or your insulin dose to keep your glucose levels normal. Your diabetes care team can advise you about the best way to do this.
If hyperglycaemia isn't treated, it can lead to a condition called diabetic ketoacidosis, where the body begins to break down fats for energy instead of glucose, resulting in a build-up of ketones (acids) in your blood.
Diabetic ketoacidosis is very serious and if not addressed quickly, it can lead to unconsciousness and eventually death.
The signs of diabetic ketoacidosis include:
Read more about the symptoms of diabetic ketoacidosis.
Your healthcare team will educate you on how to decrease your risk of ketoacidosis with a kit for testing your own blood or urine for ketones if you're unwell.
If you develop diabetic ketoacidosis, you'll need urgent hospital treatment. You'll be given insulin directly into a vein (intravenously). You may also need other fluids given by a drip if you're dehydrated, including salt solution and potassium.
Diabetes UK has more information about diabetic ketoacidosis.
If you have type 1 diabetes that's controlled using insulin or certain types of tablets, you may experience episodes of hypoglycaemia.
Hypoglycaemia is where your blood glucose levels become very low.
Mild hypoglycaemia (a "hypo") can make you feel shaky, weak and hungry, but it can usually be controlled by eating or drinking something sugary.
If you have a hypo, you should initially have a form of carbohydrate that will act quickly, such as a sugary drink or glucose tablets.
This should be followed by a longer-acting carbohydrate, such as a cereal bar, sandwich or piece of fruit.
In most cases, these measures will be enough to raise your blood glucose level to normal, although it may take a few hours.
If you develop severe hypoglycaemia, you may become drowsy and confused, and you may even lose consciousness.
If this occurs, you may need to have an injection of glucagon into your muscle or glucose into a vein. Glucagon is a hormone that quickly increases your blood glucose levels.
Your diabetes care team can advise you on how to avoid a hypo and what to do if you have one.
Type 1 diabetes can lead to long-term complications. If you have the condition, you have an increased risk of developing heart disease, stroke and kidney disease. To reduce the chance of this, you may be advised to take:
Diabetic kidney disease is identified by the presence of small amounts of a protein called albumin in your urine. It's often reversible if treated early enough.
If diabetes isn't treated, it can lead to a number of different health problems.
High glucose levels can damage blood vessels, nerves and organs.
Even a mildly raised glucose level that doesn't cause any symptoms can have damaging effects in the long term.
Prolonged, poorly controlled blood glucose levels increase the likelihood of developing atherosclerosis (furring and narrowing of your blood vessels).
This may result in a poor blood supply to your heart, causing angina (a dull, heavy or tight pain in the chest).
High blood glucose levels can damage the tiny blood vessels of your nerves.
This can cause a tingling or burning pain that spreads from your fingers and toes up through your limbs. It can also cause numbness, which can lead to ulceration of the feet.
Damage to the peripheral nervous system (the nervous system outside the brain and spinal cord) is known as peripheral neuropathy.
Diabetic retinopathy is where the retina, the light-sensitive layer of tissue at the back of the eye, becomes damaged.
The retina needs a constant supply of blood, which it receives through a network of tiny blood vessels. Over time, a persistently high blood sugar level can damage these blood vessels and affect your vision.
Annual eye checks are usually organised by a regional photographic unit. If significant damage is detected, you may be referred to a doctor who specialises in treating eye conditions (ophthalmologist).
The better you control your blood glucose levels, the lower your risk of developing serious eye problems.
Diabetic retinopathy can be managed using laser treatment if it's caught early enough. However, this will only preserve the sight you have rather than improve it.
If the small blood vessels in your kidney become blocked and leaky, your kidneys will work less efficiently.
It's usually associated with high blood pressure, and treating this is a key part of management.
Damage to the nerves of the foot can mean small nicks and cuts aren't noticed and this, in combination with poor circulation, can lead to a foot ulcer.
About 1 in 10 people with diabetes get a foot ulcer, which can cause a serious infection.
If you have diabetes, look out for sores and cuts that don't heal, puffiness or swelling, and skin that feels hot to the touch. You should also have your feet examined at least once a year.
If poor circulation or nerve damage is detected, check your feet every day and report any changes to your doctor, nurse or podiatrist.
Read more about foot care and diabetes.
In men with diabetes, particularly those who smoke, nerve and blood vessel damage can lead to erection problems. This can usually be treated with medication.
Women with diabetes may experience:
If you experience a lack of vaginal lubrication, or you find sex painful, you can use a vaginal lubricant or a water-based gel.
If your blood sugar level isn't carefully controlled immediately before and during early pregnancy, there's also an increased risk of the baby developing a serious birth defect.
Pregnant women with diabetes will usually have their antenatal check-ups in hospital or a diabetic clinic, ideally with a doctor who specialises in pregnancy care (an obstetrician).
This will allow your care team to keep a close eye on your blood glucose levels and control your insulin dosage more easily, as well as monitoring the growth and development of your baby.
The NHS diabetic eye screening programme will arrange for you to have your eyes checked every year.
Everyone who is on a diabetes register will be given the opportunity to have a digital picture taken of the back of their eye. Speak to your GP to register.
Eating a healthy, balanced diet is very important if you have diabetes. However, you don't need to avoid certain food groups altogether.
You can have a varied diet and enjoy a wide range of foods as long as you eat regularly and make healthy choices.
You don't need to completely exclude sugary and high-fat foods from your diet, but they should be limited.
If your diet is well balanced, you should be able to achieve a good level of health and maintain a healthy weight.
As physical activity lowers your blood glucose level, it's very important to exercise regularly if you have diabetes.
However, before starting a new activity, speak to your GP or diabetes care team first.
Exercise will affect your blood glucose level, so your care team may have to adjust your insulin treatment or diet to keep your blood glucose level steady.
As well as increasing this risk further, smoking also increases your risk of many other serious smoking-related conditions, such as lung cancer.
If you want to give up smoking, your GP can provide you with advice, support and treatment to help you quit.
If you have diabetes and decide to drink alcohol, avoid drinking more than the recommended daily amounts, and never drink alcohol on an empty stomach.
Depending on the amount you drink, alcohol can cause either high or low blood glucose levels (hyperglycaemia or hypoglycaemia).
Drinking alcohol may also affect your ability to carry out insulin treatment or blood glucose monitoring, so always be careful not to drink too much.
Men and women are advised not to regularly drink more than 14 units a week.
If you have diabetes, you're at greater risk of developing problems with your feet, including foot ulcers and infections from minor cuts and grazes.
This is because diabetes is associated with poor blood circulation in the feet, and blood glucose can damage the nerves.
To prevent problems with your feet, keep your nails short and wash your feet daily using warm water.
Wear shoes that fit properly, and see foot care specialists (a podiatrist or chiropodist) regularly so any problems can be detected early.
Regularly check your feet for cuts, blisters or grazes as you may not be able to feel them if the nerves in your feet are damaged.
See your GP if you have a minor foot injury that doesn't start to heal within a few days.
Read more about feet and diabetes.
If you have type 1 diabetes, you should be invited to have your eyes screened once a year to check for diabetic retinopathy.
Diabetic retinopathy is an eye condition where the small blood vessels in your eye become damaged.
It can occur if your blood glucose level is too high for a long period of time (hyperglycaemia). Left untreated, retinopathy can eventually lead to sight loss.
Read more about diabetic eye screening.
People with diabetes should also see their optician every two years for a regular eye test. Diabetic eye screening is specifically for diabetic retinopathy and can't be relied upon for other conditions.
If you have diabetes and you're thinking about having a baby, it's a good idea to discuss this with your diabetes care team.
Planning your pregnancy means you can ensure your blood glucose levels are as well controlled as they can be before you get pregnant.
You'll need to tightly control your blood glucose level – particularly before becoming pregnant and during the first eight weeks of your baby's development – to reduce the risk of birth defects.
You should also:
Your GP or diabetes care team can give you further advice.
Read more about diabetes and pregnancy.
Many people find it helpful to talk to others in a similar position, and you may find support from a group for people with diabetes.
Patient organisations have local groups where you can meet others diagnosed with the condition. Visit Diabetes UK to find your local diabetes support group.
If you want to get in touch with a trained counsellor directly, you can call the Diabetes UK Helpline on 0345 123 2399 (Monday to Friday, 9am to 7pm) or email firstname.lastname@example.org.
People with diabetes controlled by medication are entitled to free prescriptions and eye examinations.
Some people with diabetes may also be eligible for disability and incapacity benefits, depending on the impact the condition has on their lives.
The main groups likely to qualify for welfare benefits are children, the elderly, and those with learning disabilities, mental health difficulties or diabetes complications.
People over the age of 65 who are severely disabled may qualify for a type of disability benefit called Attendance Allowance.
Carers may also be entitled to some benefits, depending on their involvement in caring for the person with diabetes.
Your local Citizens Advice can check whether you're getting all the benefits you're entitled to. Your diabetes specialist nurse and Citizens Advice can also provide advice about filling in the forms.
If you need to take insulin to control your diabetes, you should have received instructions about looking after yourself when you're ill – known as your "sick day rules".
Contact your diabetes care team or GP for advice if you haven't received these.
The advice you're given will be specific to you, but some general measures that your sick day rules may include could be to:
Seek advice from your diabetes care team or GP if your blood sugar or ketone level remains high after taking insulin, if:
Type 1 diabetes occurs when the body is unable to produce insulin. Insulin is a hormone that's needed to control the amount of sugar (glucose) in your blood.
When you eat, your digestive system breaks down food and passes its nutrients – including glucose – into your bloodstream.
The pancreas (a small gland behind your stomach) usually produces insulin, which transfers any glucose out of your blood and into your cells, where it's converted to energy.
However, if you have type 1 diabetes, your pancreas is unable to produce any insulin (see below). This means that glucose can't be moved out of your bloodstream and into your cells.
Type 1 diabetes is an autoimmune condition. Your immune system (the body's natural defence against infection and illness) mistakes the cells in your pancreas as harmful and attacks them, destroying them completely or damaging them enough to stop them producing insulin.
It's not known exactly what triggers the immune system to do this, but some researchers have suggested that it may be due to a viral infection.
Type 1 diabetes is often inherited (runs in families), so the autoimmune reaction may also be genetic.
If you have a close relative – such as a parent, brother or sister – with type 1 diabetes, you have about a 6% chance of also developing the condition. The risk for people who don't have a close relative with type 1 diabetes is just under 0.5%.
Chandler Bennett was diagnosed with type 1 diabetes in October 2004.
She maintains a positive attitude to life, and has learned to manage her condition by calculating the carbohydrates in her food and taking insulin.
"When I was diagnosed, my first thought was, 'Oh my God, why me?' I used to be terrified of injections, so that side of it completely scared me.
"I was self-conscious at first. I didn't want to inject myself in front of everyone. I thought it was going to be embarrassing and everyone at school would think I was injecting drugs in the middle of lunch.
"If I hadn't taken the medication, my blood sugars would have risen and I would have started to feel dizzy. If I'd continued not taking insulin, I would have got ill, probably thrown up and eventually I would have died.
"When you have type 1 diabetes, you have to calculate the carbohydrates in your meals. A piece of toast has 20g of carbohydrates, and I have one unit of insulin for every time I eat 20g of carbohydrates.
"It was a foreign idea. I hadn't ever considered food as something to be calculated. Sometimes school lunch can be a bit difficult because you don't really know what's in everything.
"It was tricky and I made mistakes at first. You have to expect that. However, you get into a pattern and everything becomes second nature.
"It definitely affects my sports. I have to check my blood sugars more frequently when I'm playing sport. I do quite like competitive sprinting, which is difficult because adrenaline in sport brings your blood sugars up rapidly.
"A few months after I was diagnosed, I moved on to the insulin pump. It was a good change for me. It definitely gives me a lot more flexibility. It's like a bigger injection, once every three days, and it pumps in insulin throughout the day.
"Sometimes I get little red spots on my body, which makes me self-conscious when I'm going to the beach. I don't really like to wear bikinis.
"It was definitely a bit of a nightmare at first, but if you approach diabetes with a positive attitude, it just becomes another part of who you are.
"Everyone can control diabetes. You just have to put in the effort. It's worth it, because when it's controlled, you feel you're just like everybody else."
Ivy Ashworth-Crees, 59, talks about how much better her life is since her double kidney and pancreas transplant.
"About 32 years ago I was diagnosed with diabetes and had to go on insulin injections four times a day. I also had to work very hard on my diet to make sure I didn't eat too much sweet food.
"After about 25 years, I got kidney failure and in 2003 I had to go on kidney dialysis. The dialysis was very uncomfortable. It was a drain having to do it four times a day, as well as having the diabetes injections four times a day. I felt like my life was on hold.
"I was on kidney dialysis for two years when they put me on the list to have a kidney transplant. The surgeon suggested that I could probably benefit from a kidney and pancreas transplant, which meant I wouldn't have diabetes any more.
"When I got the phone call to say that I was going to Manchester for the transplant, I was absolutely hysterical. I felt many emotions and was both thrilled and terrified.
"When I came round after the operation, I was in intensive care. I stayed there for about three or four days, then they took me to the main ward.
"The most difficult part was getting out of bed, onto my feet, and starting to walk. They walked me up and down the ward for weeks until my legs got strong enough. That was very, very difficult and the pain was very bad. But it's all been worth it.
"The doctor asked me to try to reduce my weight, so I joined the gym. I enjoy swimming and I think it's helping me to keep a bit more active. The only problem is that I can't walk too far.
"It's very, very important that I take the immunosuppressant medication. If I don't take it, the kidney and pancreas could reject. I have to take them for the rest of my life.
"My life has changed such a lot. I now take it for granted that I can eat what I want, including chocolates. I'm back at work, I don't have an injection after my meals, I don't have to rush home for dialysis and my kidneys and pancreas are working well.
"I feel very blessed that I've been through this operation and it's worked very well."
Nurse consultant in diabetes, Grace Vanterpool MBE, talks about her work supporting people with diabetes and raising awareness of the condition.
Cricket star Wasim Akram's glittering career featured a series of personal battles including numerous injuries, clearing his name after match-fixing allegations and, possibly his greatest challenge, coping with type 1 diabetes.
Wasim Akram, described as the Prince of Pakistan, was the natural successor to his great mentor Imran Khan. His skill with a cricket ball seemed to defy the laws of physics and when he retired after 20 years in the game, he left an indelible mark as a supreme all-rounder and the best one-day international player in history.
Wasim was 30 when he was diagnosed with insulin-dependent diabetes.
"I remember what a shock it was because I was a healthy sportsman with no history of diabetes in my family, so I didn't expect it at all," he recalls. "It seemed strange that it happened to me when I was 30, but it was a very stressful time and doctors said that can trigger it."
The match-fixing allegations were at the heart of his stress. In a country fanatical about its national sport, Wasim was seen as a villain and his whole family felt the pressure as a result. He was eventually cleared, but he remembers that time vividly.
"I lost 8kg in a little over two months, but I put it down to hard training, drinking lots of water and sleeping a lot," says Wasim. "I faced the West Indies in that condition. My father and my wife insisted I go to the doctor and he found my sugar level was sky-high."
"I felt down at first but my wife, who qualified as a psychiatrist at UCL, helped me come to terms with it. I would advise anyone with diabetes to think positively. Adjust your lifestyle to fight it. Keeping fit and eating a very balanced diet have been crucial to keeping it under control and allowing me to continue playing. If you have control of your body, you're in control of diabetes. It's important to check blood sugar levels before meals and go for regular check-ups."
Like many people with diabetes, Wasim has had to adapt his routine and learn to inject insulin, which he takes three times a day. He also takes herbal supplements. His retirement has given him the opportunity to relax and spend more time with his family.
"Obviously I'm resting a bit more at home now rather than living out of a suitcase. I still like to keep fit by playing with my kids and I play a lot of golf. I'm 38 now so I've been managing what I eat for almost eight years and it's become part of my daily routine."
Wasim knows his responsibilities as a parent and is doing all he can to keep his two children healthy. "It's important that parents help their kids eat well and keep active, rather than watching TV and eating sweets."