Diabetes Mellitus

What is diabetes?

Diabetes mellitus is a condition where there is too much sugar in your blood. This happens because your body is unable to produce enough insulin. Insulin is a hormone that helps your body to control your blood sugar level.

There is also another kind of diabetes called diabetes insipidus. This is a disorder of the endocrine system and is very different to diabetes mellitus. For the remainder of this fact sheet, 'diabetes' refers to diabetes mellitus.

What types of diabetes are there?

There are two types of diabetes: Type 1 and Type 2.

Most people with diabetes have type 2, which is more common in older people and in those who are overweight. This type of diabetes can also run in families.

Type 1 diabetes is less common and usually starts when you are a child or a young adult and continues throughout life.

What problems does diabetes cause?

A blood sugar level that is too high can make you very unwell and you may even need to be admitted into hospital.

If you have type 1 diabetes you may feel tired, lose weight, feel constantly thirsty and pass more urine than normal.

Type 2 diabetes may cause few problems in the early stages and it is sometimes only picked up by blood tests taken as part of a routine health check or when you are unwell.

If you have had either type of diabetes for more than 10 years you are at risk of suffering from long-term complications, which include high blood pressure, heart disease and damage to your eyes and kidneys. Diabetes can also cause problems with your nerves and blood vessels, especially the ones in your legs and feet.

Your doctor may test your urine for sugar but will need to do a blood test to confirm diabetes.

What treatment will I need? 

If you have type 1 diabetes you may need a short stay in hospital when it is first diagnosed to get your sugar level back to normal. You will learn how to give yourself insulin injections once or twice a day. It is important that you eat regular meals and check how well your blood sugar level is being controlled with a home testing kit. You will need to continue the injections for the rest of your life.

For both types of diabetes, your doctor, practice nurse or nutritionist will advise you about the importance of eating a healthy diet that does not include too much sugar or fat. 

If you have type 2 diabetes your doctor may advise you on how to change your diet in order to lose weight. If this change in your diet doesn't control your blood sugar level after a few months, your doctor may give you antidiabetic tablets or insulin injections to help you feel better, but sticking to the diet is still important.

When you are taking antidiabetic tablets or insulin injections your blood sugar level can go too low without any warning and you may suffer a blackout. This happens if your dose is too high or you miss meals.

You will need regular check-ups with your doctor or practice nurse to monitor your blood sugar level, kidney function, blood pressure and eyesight.

Help yourself

  • Reduce sugar and sweet foods in your diet
  • Cut down on the fat in your diet and eat less fried food. Eat more grilled or steamed food
  • Eat more roughage such as cereals containing bran, potatoes, brown bread, green vegetables and fruit
  • Eat regular meals and always carry a snack for emergencies
  • If you are overweight try to lose weight
  • Check food labels carefully as some "low calorie" or "low fat" foods are not suitable if you have diabetes
  • Alcohol contains a lot of calories and may interfere with your diabetic treatment, so ask your doctor how much is safe to drink
  • Wear an identity bracelet that has information about your diabetes on it

Take action

  • If your sugar level goes too high or too low, or you have blackouts, contact your doctor or practice nurse
  • If you have an infection your diabetes may be affected - contact your doctor for advice if you are worried
  • The law states that drivers who have diabetes and use insulin for long term treatment or who have visual or circulatory problems must inform the DVLA. You should not drive if you have blackouts or your blood sugar levels often go too low.
  • Have your eyesight tested annually by an ophthalmic optician

Further information available from:

Diabetes UK
Central Office
Wells Lawrence House
126 Back Church Lane
London E1 1FH
Helpline: 0345 123 2399 (Monday to Friday, 9am-7pm) or helpline@diabetes.org.uk
Email: info@diabetes.org.uk
Internet: www.diabetes.org.uk 

Fact sheet provided by MIMS

Date last reviewed: October 2016

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