Diabetes

If you have diabetes, it will escalate your risk of developing cardiovascular disease. Diabetes is also associated with high blood pressure and high blood cholesterol.

9.1% of Singaporeans aged 18 to 74 years had diabetes, a increase from 5.5% in 2021-2022, and the highest prevalence was in the group of older adults between 70 to 74 years old at 22.0%, a decrease of 2.2% from 2021-2022, according to the National Population Health Survey 2024. There is no treatment that will eliminate diabetes completely, but with medication, weight management, healthy diet and physical activity, a healthier lifestyle can help you manage the disease.

What is Diabetes?

Diabetes is a chronic metabolic condition that affects how the body regulates blood glucose, commonly known as blood sugar. Understanding what diabetes is is important because persistently high blood sugar levels can gradually damage blood vessels, nerves and vital organs if left unmanaged.

Blood glucose comes from the food we eat and serves as a key source of energy for the body. Insulin, a hormone produced by the pancreas, helps move glucose from the bloodstream into the body’s cells, where it can be used for energy. When insulin production is insufficient or when the body cannot use insulin effectively, glucose accumulates in the blood instead of being absorbed by cells.

Maintaining blood glucose within a healthy blood sugar range is essential for overall health. Long-term elevation of blood sugar increases the risk of heart disease, stroke, kidney disease, vision loss and nerve damage, which is why early detection and consistent management are crucial.

Types of Diabetes

Diabetes can present in different forms depending on how insulin is produced or used in the body.

Type 1 Diabetes

Type 1 diabetes occurs when the body’s immune system attacks and destroys insulin-producing cells in the pancreas. As a result, the body produces little or no insulin, and lifelong insulin replacement is required to regulate blood glucose levels.

Type 2 Diabetes

Type 2 diabetes develops when the body becomes resistant to insulin or does not produce enough insulin to maintain normal blood glucose levels. It is the most common form of diabetes and is often associated with lifestyle factors such as excess weight, physical inactivity and ageing.

Pre-diabetes

Pre-diabetes is a condition where blood glucose levels are higher than normal but not high enough to be diagnosed as diabetes. Without lifestyle changes, pre-diabetes can progress to Type 2 diabetes, but early intervention can help reverse this condition.

Gestational Diabetes

Gestational diabetes occurs during pregnancy when hormonal changes affect how insulin works. Although it usually resolves after childbirth, women who experience gestational diabetes have a higher risk of developing Type 2 diabetes later in life.

Signs and Symptoms

People with Type 2 diabetes may have no symptoms at all. However, if there are any symptoms, they are often mild and go unnoticed. These symptoms would include:

• Having blurred vision
• Poor healing of cuts and wounds
• Feeling hungry all the time
• Itching skin especially around the genital area
• Feeling thirsty despite drinking lots of water
• Feeling tired
• Losing weight despite a good appetite
• Frequent passing of urine

Other symptoms might include vomiting, diarrhoea, constipation, erectile dysfunction and dizziness.

What Causes Diabetes?

Diabetes develops due to a combination of genetic, environmental and lifestyle-related factors that affect insulin production or use.

Genetics and Family History

Having a close family member with diabetes increases the likelihood of developing the condition, especially Type 2 diabetes.

Excess Body Weight

Carrying excess body fat, particularly around the abdomen, increases insulin resistance and makes it harder for the body to regulate blood glucose.

Physical Inactivity

A sedentary lifestyle reduces the body’s ability to use insulin effectively, leading to higher blood sugar levels over time.

Ageing

The risk of diabetes increases with age, especially after 40 years, as insulin sensitivity naturally declines.

Unhealthy Dietary Habits

Diets high in refined sugars, processed foods and unhealthy fats contribute to weight gain and insulin resistance.

Medical Conditions and Pregnancy History

Conditions such as high blood pressure, abnormal cholesterol levels and a history of gestational diabetes increase the risk of developing diabetes.

Health Complications of Diabetes

Poorly controlled diabetes can affect multiple organs and systems in the body over time.

Heart and Blood Vessel Disease

Diabetes significantly increases the risk of coronary heart disease, heart failure, stroke and peripheral artery disease due to damage to blood vessels.

Kidney Disease

High blood sugar damages the kidneys’ filtering system, potentially leading to chronic kidney disease or kidney failure.

Eye Complications

Diabetes can damage blood vessels in the retina, leading to diabetic retinopathy, vision impairment and possible blindness.

Nerve Damage

Persistently high blood glucose can damage nerves, causing numbness, tingling, pain or loss of sensation, particularly in the hands and feet.

Foot Complications

Reduced blood flow and nerve damage increase the risk of foot ulcers, infections, and in severe cases, amputation.

Cognitive and Bone Health

Diabetes has been associated with an increased risk of cognitive decline and osteoporosis, particularly in individuals with long-standing disease.

When to see a doctor?

Early detection of diabetes allows timely intervention and reduces the risk of long-term complications. You should consult a doctor if your blood glucose readings are consistently higher than normal or if you fall within a higher-risk group.

Seek medical advice if you:

• Have a fasting blood glucose level of 7.0 mmol/L or higher
• Have a family history of diabetes
• Have a history of gestational diabetes
• Are aged 40 years and above, especially with additional risk factors such as obesity or high blood pressure
• Experience symptoms such as frequent urination, excessive thirst, unexplained weight loss or persistent fatigue

Recommended Diabetes Screening

Diabetes screening is conducted using either fasting or non-fasting blood glucose tests. In Singapore, it is recommended that individuals aged 40 years and above, or those with risk factors such as family history or previous gestational diabetes, undergo health screening once every three years, or more frequently if advised by a doctor.

Common Blood Glucose Tests Used for Diagnosis

Your doctor may recommend one of the following blood glucose tests to assess your blood sugar levels.

1. Non-fasting Blood Test (HbA1c)

The HbA1c test reflects your average blood glucose levels over the past three months and does not require fasting. It is commonly used for both screening and long-term monitoring of diabetes control.

2. Fasting Blood Glucose (FBG) Test

This test measures your blood sugar level after an overnight fast of at least 8 hours and is usually done in the morning.

FBG Diagnostic Ranges

3. Oral Glucose Tolerance Test (OGTT)

The OGTT involves two blood tests:

• The first after an 8-hour fast
• The second 2 hours after consuming a glucose-rich beverage

This test assesses how effectively your body processes glucose over time.

OGTT Diagnostic Ranges

Living Well with Diabetes

Lifestyle changes such as maintaining a healthy BMI, eating healthy and engaging in regular, moderate-intensity aerobics physical activity may reduce the progression of pre-diabetes and Type 2 diabetes and control Type 1 diabetes. They can also minimise other risk factors such as high blood pressure, high blood cholesterol, heart attack and stroke.

In many instances, medications must be accompanied to better control blood glucose levels.

Healthy Diet

For patients with pre-diabetes or diabetes, it is important to watch their diet, one way would be to limit the intake of refined sugars and foods that release sugar during digestion, including starches, breads and fruits. They can include the following ingredients for a better diet:

• Healthy carbohydrates like whole-grains, legumes (e.g., beans, peas and lentils), fruit and vegetables. During digestion, sugars (simple carbohydrates) and starches (complex carbohydrates) break down into blood glucose. Look for foods that is low with Glycaemic Index (GI) as higher in GI would suggest a higher blood glucose.
• Fibre-rich foods such as vegetables, fruit, legumes, whole-wheat flour and wheat bran. Dietary fibre includes all parts of plant foods that your body cannot digest or absorb.
• Heart healthy fishes at least twice a week. For example, cod, tuna and halibut have lesser total fat, saturated fat and cholesterol than most meat and poultry. Fish such as salmon, mackerel, tuna and sardines are rich in omega-3 fatty acids, which promote heart health by lowering blood fats called triglycerides. Avoid fried fish and fish with high levels of mercury, such as tilefish, swordfish and king mackerel.
• Good fats but in moderation like avocados, nuts (e.g., almonds, pecans and walnuts), healthier oils (e.g., canola and olive oil). Foods containing monounsaturated and polyunsaturated fats can help lower your cholesterol levels.

Active Lifestyle

Regular physical activity helps lower insulin resistance. This means your body can use its own insulin more effectively. For your overall cardiovascular health, aim for 150 – 300 minutes of moderate-intensity aerobic physical activity each week and incorporate muscle and bone strengthening activities (e.g., weight training, pilates, body weight calisthenics) at least 2 times per week. Join some class exercises if you enjoy working out with peers and like-minded friends.

Medication

Patients with type 2 diabetes will be given medication if lifestyle changes are not sufficient to lower their blood sugar. Some medications will include:

Key Takeaways on Diabetes Management

Diabetes is a long-term condition that requires ongoing care and self-management. With early detection, healthy lifestyle choices and appropriate treatment, individuals can control blood sugar levels and significantly reduce the risk of heart disease, stroke and other serious complications. Taking proactive steps today supports long-term heart and metabolic health.

Understanding the Diabetes and Heart Health Webinar

This educational webinar brings together cardiologists and endocrinology specialists to explore the close relationship between diabetes, obesity and heart disease. It provides practical insights into managing risk factors, understanding disease progression and adopting heart-healthy habits to support long-term well-being.

Frequently Asked Questions

What is a healthy blood sugar range for adults?

A healthy blood sugar range generally refers to fasting blood glucose levels below 6.0 mmol/L. Target ranges may vary depending on age, medical conditions and individual health goals.

What is diabetes, and why is it serious?

Diabetes is a condition where blood sugar levels remain persistently high due to insulin problems. Over time, it increases the risk of heart disease, kidney failure, nerve damage and vision loss.

Can diabetes be reversed?

Pre-diabetes can often be reversed through lifestyle changes such as diet and physical activity. Diabetes itself is not reversible, but it can be effectively managed to prevent complications.

How often should blood sugar be checked?

The frequency depends on individual risk and treatment plans. People with diabetes may need daily monitoring, while those at risk should follow screening recommendations from their doctor.

Does diabetes increase heart disease risk?

Yes, diabetes significantly raises the risk of cardiovascular disease. Good blood sugar control helps protect blood vessels and reduces heart-related complications.