Type 2 diabetes: What is it?

Diabetes is a long-term condition that affects the body's ability to convert sugar into energy. This allows sugar levels to build up in the blood, which can lead to heart disease, blindness and other serious complications. Type 2 diabetes can affect people of all ages and early symptoms are subtle. Diabetes UK estimates that around a million people in the UK with type 2 diabetes don't know they have it. Learn to spot the warning signs in this slideshow.

Diabetes may not have symptoms

In most cases type 2 diabetes doesn't cause any symptoms, or the symptoms are mild, which is why many people have it for years without knowing it, and why it's important to get tested.

Warning sign: Thirst

One of the first symptoms of type 2 diabetes may be an increase in thirst. This is often accompanied by additional problems, including dry mouth, increased appetite, frequent urination - sometimes as often as every hour - and unusual weight loss or gain.

Warning sign: Blurred vision

As blood sugar levels become more abnormal, additional symptoms may include headaches, blurred vision and fatigue.

Warning sign: Infections

In most cases, type 2 diabetes is not discovered until it takes a noticeable toll on health. Look out for problems such as:

• Cuts or sores that are slow to heal
• Frequent fungal infections
• Itchy skin, especially in the groin area

Diabetes warning sign: Sexual dysfunction

Sexual dysfunction is common among people with diabetes. Diabetes can cause damage to blood vessels and nerve endings in the genitals, leading to a loss of feeling and making orgasm difficult. Other complications can include vaginal dryness in women and erection problems in men.

Risk factors you can control

Your habits and lifestyle can affect your odds of developing type 2 diabetes. Factors that increase your risk include:

• Being overweight, defined as a body mass index (BMI) of 25 or more
• Sedentary lifestyle

Risk factors you can't control

Other risk factors are out of your control, including:

• Race or ethnicity: South Asian and African Caribbean people have a higher than average risk
• Family history of diabetes: having a parent or brother or sister with diabetes increases your risk
• Age: being 45 and older increases your risk of type 2 diabetes

The more risk factors you have, the greater your chances of developing type 2 diabetes.

Risk factors for women

Having gestational diabetes when you're pregnant puts you seven times at greater risk of developing type 2 diabetes later on. Women who've given birth to a large baby weighing more than 4.5kg (9.9 pounds) are more likely to develop gestational diabetes in future pregnancies. Having a history of polycystic ovary syndrome (PCOS) can also cause insulin resistance that can lead to diabetes.

Type 2 diabetes in children

Although older people have a higher risk of getting type 2 diabetes, the condition is affecting more young people. Diabetes UK says around 31,500 children and young people in the UK have diabetes, with around 600 of these having type 2 diabetes. The leading risk factor for children is being overweight, often connected with an unhealthy diet and lack of physical activity. Once children are overweight, their chances of developing type 2 diabetes more than doubles.

Diagnosing type 2 diabetes

There's no need for guesswork in diagnosing type 2 diabetes. Often a urine test is carried out first, and if it contains glucose, or a person is at risk of diabetes, one or more blood tests to check levels of glucose in the blood are performed. A glucose tolerance test or GTT may also be recommended. Also, a blood test called the HbA1c test may be used to help make a diagnosis of diabetes.

How does insulin work?

In healthy people, after a meal food is broken down into a sugar called glucose, which is carried by the blood to cells throughout the body. Cells use the hormone insulin, made in the pancreas, to help them process blood glucose into energy. People develop type 2 diabetes because the cells in the muscles, liver and fat cannot use insulin properly, called insulin resistance.

Type 2 Diabetes: Metabolism mishaps

In type 2 diabetes, the cells cannot absorb glucose properly. That means glucose levels in the blood become elevated. If you've developed a condition called insulin resistance, the body makes insulin, but the muscle, liver and fat cells cannot use insulin, or do not respond to the insulin, properly. With long-standing, uncontrolled type 2 diabetes, the pancreas will reduce the amount of insulin it produces.

Managing diabetes: Diet

Fortunately, people with type 2 diabetes can significantly reduce the risk of damage to their bodies, including damage to the heart, kidneys, eyes and feet. The key is controlling blood sugar levels by changing diet. People with type 2 diabetes should carefully monitor carbohydrate consumption, as well as total fat and protein intake and reduce calories.

Managing diabetes: Exercise

Moderate exercise, such as strength training or walking, improves the body's use of insulin and can lower blood sugar levels in people with type 2 diabetes. Being active also helps reduce body fat, lower blood pressure and protect against heart disease. Try to do at least 150 minutes of exercise a week, with some exercise on most days of the week.

Managing diabetes: Stress reduction

Stress can cause blood pressure to rise. It can also increase glucose levels in your blood as part of your "fight or flight" response. Or you may turn to comfort foods to cope with stress. All can be bad when living with diabetes. Instead of letting stress take its toll, try relaxation techniques such as deep breathing, meditation or just talking to a friend or relative. If these don't work for you, seek medical advice.

Managing diabetes: Medication

When people with type 2 diabetes are unable to control blood sugar sufficiently with diet and exercise, medication can help. There are many types of diabetes drugs available and they are often used in combination. Some work by stimulating the pancreas to make more insulin, while others improve the effectiveness of insulin, or reduce the liver’s production of glucose, or block the digestion of starches.

Managing diabetes: Insulin

Many people with type 2 diabetes eventually develop 'beta-cell failure'. This means the cells in the pancreas no longer produce insulin in response to high blood sugar levels. In this case, insulin therapy – injections or an insulin pump – must become part of the daily routine.

Non-insulin injectables

New drugs are available for people with type 2 diabetes. These drugs are non-insulin injectable drugs. Whereas insulin pulls glucose into the cells, these medications cause the body to release insulin to control blood sugar levels.

Glucose testing

Testing your blood glucose level will let you know how controlled your blood sugars are and if you need to take action to change your treatment plan. How often and when you test will be based on how controlled your diabetes is, the type of therapy used to control your diabetes and whether you are experiencing symptoms of fluctuating sugars. Your diabetes team will suggest how often you should use a glucose meter to check your blood sugar. Common testing times are first thing in the morning, before and after meals and exercise and before bedtime.

Long-term damage: Arteries

Over time, untreated type 2 diabetes can damage many of the body's systems. People with diabetes are likely to develop plaque in their arteries, which reduces blood flow and increases the risk of clots. This increases the risk of heart attack and stroke. People with diabetes are up to five times more likely to develop heart disease or have a stroke.

Long-term damage: Kidneys

The longer you have untreated diabetes, the greater the risk of developing kidney disease or kidney failure. Patients with kidney failure must get a kidney transplant or rely on dialysis to survive.

Long-term damage: Eyes

High blood sugar can damage the tiny blood vessels that bring oxygen and nutrients to the retina, a critical part of the eye. This is known as diabetic retinopathy and it can cause progressive, irreversible vision loss. People with diabetes are up to 20 times more likely to go blind than those without diabetes. Pools of blood, or haemorrhages, on the retina of an eye are visible in this image.

Long-Term Damage: Nerve Pain

Over time, uncontrolled diabetes and elevated blood sugars create a very real risk of nerve damage. Symptoms can include tingling, numbness, pain and a pins and needles sensation - often in the fingers, hands, toes or feet. The damage is not reversible, but treatments can help with the pain and numbness. Controlling your diabetes can help prevent further damage.

Long-term damage: Feet

People with diabetes often experience nerve damage that can make it more difficult to feel their feet.  At the same time, narrowing of the arteries results in poor blood flow to the feet. Foot sores and gangrene can occur. In severe cases, the foot or leg must be amputated.

Preventing type 2 diabetes

One of the most astonishing things about type 2 diabetes is that such a life-altering condition is often preventable. To lower your risk, follow the same guidelines for warding off heart disease:

• Eat a healthy diet
• Exercise for at least 150 minutes a week
• Maintain a healthy weight
• Talk to your GP about being screened for diabetes

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