long lasting high sugar

Overview

Long-lasting high blood sugar means the level of sugar (glucose) in your blood stays higher than normal for a long time. Glucose is a main source of energy for your body. A hormone called insulin — made by your pancreas, an organ behind your stomach — normally helps move glucose from your blood into your cells. When your body doesn't make enough insulin or stops using it well, glucose builds up in the blood. This condition is also called hyperglycemia.

Yes, it is very common. Many people around the world have high blood sugar without knowing it. In the UK, the NHS offers routine checks for people at risk.

It can affect anyone, including children and older adults. You are more likely to develop it if you are overweight, have a family history of diabetes, are over 40, or have high blood pressure. It can also happen during pregnancy (gestational diabetes) or after certain illnesses or medicines.

Symptoms

Common symptoms

• Feeling very thirsty more than usual
• Needing to urinate often, especially at night
• Feeling tired or having low energy
• Blurred eyesight
• Headaches
• Dry or itchy skin

Symptoms in children

• Children may show signs such as drinking a lot more water, going to the bathroom often, bedwetting after being dry at night, weight loss even though they eat more, and feeling unusually tired. They may also act more irritable or have trouble paying attention.

Symptoms in older adults

• In older adults, symptoms can be more subtle. They may feel confused, dizzy, or unsteady. Sometimes an older person doesn't feel thirsty even when blood sugar is high, so symptoms can be missed. If an older adult seems suddenly confused or unwell, check with a healthcare professional.

Causes

Main causes

• Your body does not make enough insulin (the hormone that lowers blood sugar)
• Your cells become less responsive to insulin (called insulin resistance)
• Some medicines for other health conditions can raise blood sugar
• Long-term stress, illness, or infection can push blood sugar up
• Eating a lot of refined or sugary foods over time can overload your body's sugar control systems

Risk factors

• Being over 40 years old
• Being overweight or having extra weight around your belly
• Having a parent or sibling with type 2 diabetes
• Being of South Asian, Afro-Caribbean, or Middle Eastern heritage (higher risk for type 2 diabetes)
• Having high blood pressure, high cholesterol, or heart disease
• Having had diabetes during pregnancy

When to see a doctor

See a doctor urgently if:

• If you have symptoms of high blood sugar like extreme thirst, frequent urination, unexplained weight loss, or blurred vision
• If you are experiencing confusion, severe drowsiness, or breathing difficulty, call your local emergency number right away

Diagnosis

Doctors use a blood test to check your blood sugar level. The test may be done after fasting (no food for at least 8 hours) or at any time, depending on your symptoms.

Tests that may be done

• Fasting blood sugar test — shows your blood sugar after you have had no food for at least 8 hours.
• HbA1c test — measures your average blood sugar over the past 2 to 3 months. No fasting is needed.
• Oral glucose tolerance test — you fast, then drink a sweet liquid, and your blood is checked to see how well your body processes the sugar.

What to expect at your appointment

If your blood sugar is high, your doctor will often do a second test to confirm the result before offering a diagnosis. The test is simple and results are usually available within a day or a few days. If you are diagnosed, your healthcare team will talk with you about next steps and support you can get.

Treatment

Treatment for long-lasting high blood sugar focuses on keeping your blood sugar in a healthy range. This is usually achieved with lifestyle changes first. Some people also need medicines to help their body use sugar properly.

Self-care at home

• Learn to plan meals around vegetables, whole grains, and lean proteins.
• Move your body for at least a little while after meals — a short walk can help lower blood sugar.
• Check your blood sugar at home if your doctor shows you how and recommends it.
• Stay hydrated by drinking water or unsweetened drinks.
• Keep a consistent daily routine for meals and activity.

Medical treatments

If lifestyle changes aren't enough, your doctor may prescribe medicines that help your body release insulin, use insulin better, or lower the amount of sugar your liver makes. Some medicines are taken as tablets; others are injections. The medicine your doctor chooses depends on your health needs. Your pharmacist or doctor can explain how to take your medicine and what side effects to look for. Do not change or stop any medicine without talking to your healthcare provider.

When is surgery considered?

In some cases of severe obesity and type 2 diabetes, weight-loss (bariatric) surgery can help improve blood sugar control. This is not a first-line treatment and is only considered after a specialist review, when lifestyle measures and medicines have not achieved the target. It’s not suitable for everyone.

Living with this condition

Living with long-lasting high blood sugar involves building a simple daily routine. You may check your blood sugar at certain times, plan balanced meals, take medicines as prescribed, and wear comfortable shoes to protect your feet. Over time, these small habits become automatic.

Lifestyle tips

• Eat more non-starchy vegetables, like leafy greens, broccoli, and peppers.
• Choose whole-grain bread and rice over white versions.
• Limit sugary drinks, sweets, and processed snacks.
• Try to be active for at least 150 minutes per week — you can start with 10-minute walks.
• Aim for 7–9 hours of sleep each night; a regular bedtime helps.

Diet and exercise

A balanced plate is a helpful way to eat: fill half your plate with vegetables, one quarter with proteins like fish, chicken, beans or tofu, and one quarter with starchy foods like potatoes or wholegrain rice. Exercise — moderate activity that makes you breathe a bit harder, like brisk walking or cycling — helps your body use insulin more effectively. If you are new to exercise or have other health conditions, speak to your doctor before starting a new routine.

Mental health and emotional wellbeing

Coping with a long-term condition can feel overwhelming at times. You may worry about your health or feel guilty when your numbers are off. This is normal. Anxiety and depression are more common in people with high blood sugar. Please talk to your healthcare team if you are feeling down. If you ever have thoughts of harming yourself, get help immediately by calling your local emergency number.

Prevention

For many people, high blood sugar can be prevented or delayed. The most effective ways are keeping a healthy weight, staying active, eating a balanced diet, and getting regular health checks. However, some forms, such as type 1 diabetes, cannot be prevented. If you have a medical condition that raises blood sugar, talk to your doctor about what you can do.

Screening programmes

Screening means having a blood test to look for high blood sugar before you have symptoms. Guidelines in the UK suggest that adults over 40, people with risk factors, and people from certain ethnic groups should be screened. Your doctor or local health service can tell you if a screening test is right for you.

Complications

If left untreated

• Heart disease and stroke from damaged blood vessels
• Kidney disease, which can lead to kidney failure
• Nerve damage causing pain, numbness, or tingling in hands and feet
• Vision problems, including diabetic retinopathy, which can lead to blindness
• Slow-healing wounds and infections, especially on the feet, that may lead to amputation

Long-term outlook

If you have long-lasting high blood sugar, you still have full control over many parts of your life. With the right support and consistent care, you can reduce your risk of complications and live well. Many people with this condition learn how to manage it and enjoy healthy, satisfying lives. It’s never too late to take a step in the right direction.

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