Diabetes is a lifelong condition that causes a person's blood sugar level to become too high.

There are two main types of diabetes:

  • type 1 diabetes – where the body's immune system attacks and destroys the cells that produce insulin
  • type 2 diabetes – where the body doesn't produce enough insulin, or the body's cells don't react to insulin

Type 2 diabetes is far more common than type 1. In the UK, around 90% of all adults with diabetes have type 2.

During pregnancy, some women have such high levels of blood glucose that their body is unable to produce enough insulin to absorb it all. This is known as gestational diabetes.

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Many more people have blood sugar levels above the normal range, but not high enough to be diagnosed as having diabetes.

This is sometimes known as pre-diabetes. If your blood sugar level is above the normal range, your risk of developing full-blown diabetes is increased.

It's very important for diabetes to be diagnosed as early as possible because it will get progressively worse if left untreated.

When to see a doctor

Visit your GP as soon as possible if you experience the main symptoms of diabetes, which include:

  • feeling very thirsty
  • urinating more frequently than usual, particularly at night
  • feeling very tired
  • weight loss and loss of muscle bulk
  • itching around the penis or vagina, or frequent episodes of thrush
  • cuts or wounds that heal slowly
  • blurred vision

Type 1 diabetes can develop quickly over weeks or even days.

Many people have type 2 diabetes for years without realising because the early symptoms tend to be general.

Causes of diabetes

The amount of sugar in the blood is controlled by a hormone called insulin, which is produced by the pancreas (a gland behind the stomach).

When food is digested and enters your bloodstream, insulin moves glucose out of the blood and into cells, where it's broken down to produce energy.

However, if you have diabetes, your body is unable to break down glucose into energy. This is because there's either not enough insulin to move the glucose, or the insulin produced does not work properly.

There are no lifestyle changes you can make to lower your risk of type 1 diabetes.

You can reduce the risk of developing type 2 diabetes through healthy eating, regular exercise and maintaining a healthy body weight.

Living with diabetes

If you're diagnosed with diabetes, you'll need to eat healthily, take regular exercise and carry out regular blood tests to ensure your blood glucose levels stay balanced.

You can use the BMI healthy weight calculator to check whether you're a healthy weight.

People diagnosed with type 1 diabetes also require regular insulin injections for the rest of their life.

As type 2 diabetes is a progressive condition, medicine may eventually be required, usually in the form of tablets.

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Before you travel

  • make sure your travel insurance covers health problems related to your diabetes
  • find out where you can get insulin in the place you're travelling to
  • speak to your care team for advice about adjusting to different time zones
  • if you're flying, get a letter from your GP to say you have diabetes and need to take your treatment on to the plane
  • if you use a pump or CGM, check with your airline before you travel about taking it on board – some airlines require paperwork for medical equipment

Packing for your trip

  • pack 3 times as much insulin, test strips, lancets, needles and glucose tablets as you'd expect to need
  • if you use a pump, pack insulin pens in case it stops working
  • put insulin in your hand luggage – the hold of the plane will be too cold and could damage the insulin
  • take a cool bag to stop your insulin getting too hot
  • take plenty of snacks in case there are any delays
  • do not put your pump through the hand luggage scanner – let airport security know so they can check it another way

While you're away

  • be prepared to test more while you're away – hot and cold weather can affect your blood glucose levels and increase your risk of a hypo or hyper
  • you may have to change your insulin dose depending on the temperature and different activities you're doing – speak to your diabetes team

Diabetes UK has more information on what to do when you travel.

Diabetic retinopathy

Diabetes and your eyes

Everyone with diabetes aged 12 or over should be invited to have their eyes checked for changes due to diabetes once a year.

If you have diabetes, your eyes are at risk from diabetic retinopathy, a condition that can lead to sight loss if it's not treated.

Screening, which involves having drops in your eyes to see the back of your eye better, and having photographs taken, is a way of detecting the condition early so it can be treated more effectively

Read more about diabetic eye screening.

The diabetic screening only checks for changes due to diabetes. Having diabetes means you may be more likely to get other eye conditions like glaucoma or cataracts so it is also important that you have a regular eye examination (which will be free on the NHS) with your local optometrist/optician.

Find an optometrist/optician here

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA)? 

Diabetic ketoacidosis is a?serious problem that can occur in people with?diabetes?if their body starts to run out of insulin. 

This causes harmful substances called ketones to build up in the body, which can be life-threatening if it's not found and treated quickly. 

Read more about diabetic ketoacidosis.

The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website nhs.uk
Last Updated: 17/03/2023 15:16:11