Type 1 diabetes: symptoms, complications and treatment

Almost six million people in the UK have diabetes; however, fewer than one in 10 of these individuals have type 1 diabetes. Type 1 diabetes occurs when your body can’t make the hormone insulin, which regulates the levels of sugar (glucose) in your blood when you eat and drink. 

Here, we will explore what type 1 diabetes is, how it differs from type 2 diabetes, common symptoms and complications, and how it is treated and managed. 

But first, to understand type 1 diabetes, it helps to understand how your body normally controls your blood glucose levels. 

How your body controls your blood sugar levels

When you eat food or have a drink containing sugar, your digestive system breaks down the food or liquid into components that can be absorbed into your bloodstream via your gut. This allows nutrients and energy from your food to be delivered to your cells. 

This is also why when you eat a meal, levels of the sugar glucose in your blood rise — carbohydrates and sugars in your food are all broken down into glucose. Your pancreas detects that your blood glucose levels have risen and produces the hormone insulin from pancreatic cells called beta cells. 

Insulin is released into your blood and tells the cells in your body to take up glucose from your blood either to use as energy straight away or to store for later use. This causes your blood glucose levels to drop back down. 

Type 1 diabetes vs type 2 diabetes 

In type 1 diabetes, very little or no insulin is produced by the pancreas. This is because the beta cells of the pancreas, which are responsible for making insulin, have been mistakenly destroyed by the body’s immune system. 

Consequently, in type 1 diabetes, when you eat a meal and your blood glucose levels rise, your body’s cells can’t take up the glucose and glucose levels in your blood remain high. 

In contrast, in type 2 diabetes, the pancreas still makes insulin but may not make enough insulin or the body’s cells no longer respond properly to the insulin ie the cells become insulin resistant. 

Lifestyle factors, such as diet and exercise, have a major role to play in the development of type 2 diabetes. However, lifestyle factors do not affect your risk of type 1 diabetes and there is nothing you can do to prevent its onset. Consequently, type 2 diabetes can be reversed, while type 1 diabetes cannot.

Both type 1 and type 2 diabetes have a genetic component and your risk of developing either is higher if you have a family history of these conditions.

Symptoms of type 1 diabetes

Symptoms of type 1 diabetes develop very quickly over several days or weeks and can occur at any age, although almost always before age 40 and usually during childhood. 

Common symptoms include feeling very thirsty and tired, urinating more often, unintentionally losing weight and having sweet- or fruity-smelling breath. You may also notice that any wounds you have aren’t healing as quickly as usual and that you get infections frequently (eg thrush and urinary tract infections (UTIs)). 

If you notice these symptoms, you should see your GP as soon as possible. If left untreated, a life-threatening condition called diabetic ketoacidosis can develop within 24 hours. 

Diabetic ketoacidosis occurs when your body’s cells can’t absorb the glucose in your blood for energy. This triggers your liver to start breaking down fat as an energy source. However, this produces ketones, which build up in your blood, making your blood acidic. This causes stomach pain, nausea, vomiting, blurred vision, diarrhoea, fatigue, confusion and laboured breathing.

If you have symptoms of diabetic ketoacidosis, go to A&E or call 999.

Getting a diagnosis  

Type 1 diabetes is usually diagnosed using a pinprick blood test that measures the levels of glucose in your blood. 

You may also have a Hb1Ac blood test that measures how much blood glucose is attached to the haemoglobin in your blood. The results of this test give your doctor an idea of your average blood glucose levels over the last two to three months. 

Your doctor may also recommend a urine test to measure levels of glucose and ketones in your urine. Ketones may be present in your urine if you have developed diabetic ketoacidosis as a result of type 1 diabetes.

Managing type 1 diabetes

The main treatment for type 1 diabetes is taking insulin; however, you will also need to make changes to your diet to help control your blood glucose levels. 

Your diabetes care team will discuss what types of insulin you need to take and when. In most cases, you will need to take both long-acting insulin one to two times every day and short-acting insulin before you eat. 

You will either need to administer insulin yourself as injections using an insulin pen or you will be fitted with an insulin pump that is attached to your body. This delivers insulin continuously throughout the day and again when you instruct it to do so before meals. Your diabetes care team will train you on how to use either an insulin pen or insulin pump. 

In addition, you will need to regularly check your blood glucose levels throughout the day using a continuous glucose monitor — this is available on the NHS to everyone diagnosed with type 1 diabetes and involves wearing a small sensor on your arm or abdomen. This will help you determine if your blood glucose levels are well-controlled and if you are taking the correct amount of insulin. 

You will also have Hb1Ac blood tests administered by your diabetes care team two to four times every year, which will show how well your diabetes is controlled over the year. 

In addition to glucose monitoring and taking insulin, you will need to follow a healthy, balanced diet that is low in sugar, salt and saturated fats. You will also need to monitor how much carbohydrate you are eating and drinking so that you can adjust how much insulin you need to take.

Regular exercise is also important to help control your blood sugar levels in the long-term. 

Your diabetes care team will teach you about how diet, exercise and illness affect your blood glucose levels, so that you can adjust your insulin levels accordingly. 

Complications of type 1 diabetes

Living with diabetes can be a significant adjustment, which is why your diabetes care team will provide you with advice and support on how to manage your diet and lifestyle to better control your blood glucose levels. 

However, you may still experience short-term complications when your blood glucose levels are too low (hypoglycaemia) because you haven’t eaten enough or have taken too much insulin, or when your blood glucose levels are too high (hyperglycaemia) because you haven’t taken enough insulin. Your care team will advise you on the symptoms to watch out for and how to treat these episodes quickly and effectively.

In the long-term, poorly controlled type 1 diabetes can lead to multiple complications that affect different parts of your body. This includes diabetic retinopathy, which can permanently damage your vision, diabetic neuropathy, which damages your nerves, and diabetic nephropathy, which damages your kidneys. 

You are also at higher risk of having foot problems due to a combination of diabetic neuropathy affecting the nerves in your feet and poor blood supply due to high blood glucose levels damaging your blood vessels. This can damage the tissue in your feet and prevent wounds here from healing. In extreme cases, this can lead to amputation. 

Damaged blood vessels due to poorly controlled type 1 diabetes can also reduce blood supply to your sexual organs. In women, this can reduce sensations in the genital area during sex and in men, this can cause erectile dysfunction.

Your risk of gum disease, heart attack, stroke and certain cancers is also higher if your type 1 diabetes is not well-controlled. 

You can, therefore, reduce your risk of these long-term complications by regularly monitoring your blood glucose levels and carbohydrate intake, so that you can more consistently take the appropriate amount of insulin to keep your blood glucose levels within a safe target range. 

Type 1 diabetes in children

Type 1 diabetes usually develops during childhood, particularly between the ages of four to seven and 10 to 14 years. 

While adjusting to life with type 1 diabetes can be challenging, with the right support, children continue to thrive and can lead full, healthy lives. 

It is important to closely monitor your child’s blood glucose levels and diet so that they can receive the correct amount of insulin. 

In addition to the physical effects of poorly controlled type 1 diabetes mentioned above, children can also struggle with concentration, memory, processing and attention at school. 

All schools in the UK have procedures in place to support children with diabetes so you can work with your child’s school to make sure they receive the care they need during school hours.

Living with type 1 diabetes

Living with type 1 diabetes involves careful planning of your meals, exercise, work and/or school life and outings. This can be mentally and emotionally challenging, which is why it is important to tell your friends, family, work colleagues and/or school teachers about your type 1 diabetes. They can then learn about how best to support you and be aware of symptoms of hypoglycaemia and hyperglycaemia. 

To help you adjust to life with type 1 diabetes, there are several freely available courses including DAFNE (Dose Adjustment for Normal Eating), which is designed to help you learn how to follow a diabetes-friendly diet with as little disruption to your usual life as possible. 

BERTIE Diabetes and My Type 1 Diabetes also provide a range of online courses on different aspects of living with type 1 diabetes, including carbohydrate counting, emotional wellbeing, exercising, eating out and managing your type 1 diabetes when ill.