Since 2006, World Diabetes Day is marked every year on November 14th to raise global awareness of diabetes. In the past, diabetes was commonly thought of as a chronic illness affecting middle-aged and elderly people. However, recent statistics have shown that with changes in living environments, daily routines and dietary habits, the risk of diabetes is no longer limited to middle-aged and elderly individuals. Currently, there are about 700,000 diabetic patients in Hong Kong, accounting for 10% of the total population, which means that one out of every ten people has diabetes, and there is a trend of younger onset. Therefore, diabetes is now a disease that requires attention from the general public. Although diabetes cannot be cured, establishing good lifestyle and dietary habits can help control the condition and enable patients to lead a quality life. In this article, three doctors from different specialities will share detailed information about diabetes, deepening your understanding of this disease and helping you to prevent it.

Dr Wong Cheuk Lik (Specialist in Endocrinology, Diabetes & Metabolism)

Dr Wong Cheuk Lik stated that the causes of diabetes vary depending on the type. Type 1 diabetes is caused by insufficient insulin due to an autoimmune problem where antibodies attack pancreatic cells. Type 2 diabetes is caused by severe insulin resistance that is often caused by genetics. Patients often have a family history of the disease and are influenced by extrinsic factors such as lack of exercise and obesity. In addition to insulin resistance or deficiency, diabetes is also related to other factors such as abnormal secretion of certain gut hormones like incretins, and greater glucose absorption by renal tubules. Diabetic patients may find that the alpha cells in their pancreas release too much glucagon, which can lead to type 2 diabetes. In addition, there are genetic or special forms of diabetes, including MODY (maturity-onset diabetes of the young) and mitochondrial diabetes. In addition to the above causes, some cases of diabetes are caused by medication, such as steroids, or are due to endocrine disorders.

For high-risk individuals, the focus is mainly on type 2 diabetes. For people with obesity, a family history of the disease such as a parent or sibling with diabetes, a history of gestational diabetes or polycystic ovary syndrome, or high cholesterol levels, they have a higher risk of developing diabetes and are recommended to have a check-up after the age of 35.

Early diabetes has no symptoms, so early screening and treatment are important. By the time when symptoms appear, patients often have developed complications and high blood sugar problems. If you often have a dry mouth or experience sudden weight loss or an increase in appetite, these may be signs of high blood sugar levels or type 1 diabetes. More serious symptoms include ketoacidosis, systemic discomfort, difficulty breathing and stomachache.

Diabetes can also trigger other complications, including diabetic retinopathy, blurred vision, retinal or vitreous haemorrhage, which can affect vision. Diabetes can also affect the kidneys and lead to diabetic nephropathy, diabetic neuropathy, diabetic eye disease, diabetic fractures, osteoporosis, and cardiovascular problems such as coronary heart disease, stroke, and fatty liver disease. Obese diabetic patients with fatty liver disease are at risk of developing cirrhosis and liver cancer in the long run.

Diabetes can also cause numbness and tingling in the hands and feet. In some severe cases, patients may have diabetic feet with infected ulcers and are only diagnosed with diabetes upon hospitalization. Other symptoms include skin changes, such as brown round patches on the feet and itching that feels like a fungal infection in the lower body.

To prevent diabetes, weight control, dietary changes and exercise are essential. A large-scale study has shown that the combination of dietary changes, exercise and a 5-10% reduction in body weight is more effective than medication. Plus, there are currently medications available to help prevent diabetes, with the most common being metformin. As for middle-aged and elderly people, the reasons for developing diabetes are similar to those of the general population. However, their insulin secretion capacity gradually declines as they age. Lack of exercise also leads to decreased muscle glucose utilization and sensitivity, indirectly leading to reduced insulin sensitivity. A sedentary lifestyle can cause midlife obesity, which can increase insulin resistance. Central obesity also causes visceral fat to release adipokines, leading to inflammation and insulin resistance. Other common mid and late-life illnesses such as joint degradation can make patients less willing to walk, which can intensify the condition. Some middle-aged and elderly people may develop diabetes due to medication issues, such as taking steroid medications (a drug used to treat many diseases), which can worsen blood sugar control and increase the risk of diabetes.

Adopt a Mediterranean diet

In terms of dietary habits, it is essential to maintain a balanced and healthy diet, and there is currently no international guideline on which dietary pattern is the best. However, clinical studies have found that a Mediterranean diet, which emphasizes plant-based foods such as vegetables, legumes, nuts, seeds, fruits and grains, as well as fish, seafood and dairy products, can help prevent the risk of developing diabetes and some cholesterol and cardiovascular diseases. It is also recommended to use vegetable oils like olive oil.

Other dietary patterns include a vegetarian or low-fat diet. A low-fat diet is one in which fat accounts for less than 30% of total daily calorie intake. On the other hand, a low-carbohydrate diet can help prevent sugar spikes and reduce the chance of gaining weight. In a low-carbohydrate diet, carbohydrates should account for less than 30-40% of total daily calorie intake. Other dietary recommendations include choosing foods with a low glycaemic index and eating fewer ultra-processed foods.

Meal sequencing for blood sugar control

Eating vegetables and meat before eating carbohydrates can slow down absorption and thus reduce the speed of blood sugar spikes. When eating carbohydrates, it is recommended not to consume large amounts at once, but to evenly distribute them throughout the day to slow down the speed of blood sugar spikes. Since everyone's nutritional needs are different, it is important to consult a dietitian to determine the appropriate portion sizes. But here is a general guideline: you can allocate about 40 grams of carbohydrates for breakfast, and 50-60 grams for lunch or dinner, with a small amount of snacks in between.

Avoid excessive absorption of hidden carbohydrates

Many patients are unaware of the sources of carbohydrates. Apart from grains such as rice, noodles and bread, root vegetables such as potatoes, pumpkins, sweet potatoes, lotus roots and kudzu roots often are overlooked sources of carbohydrates. These vegetables are often used to make soups, and even if the solids are not consumed, the carbohydrates will dissolve into the soup and cause blood sugar spikes.

Eat fruits with their skin on to slow down blood sugar spikes

When eating fruit, it is important to pay attention to portion size. Some fruits can be washed and eaten with the skin, as dietary fibre can slow down the speed of blood sugar spikes. In addition, dairy products also contain carbohydrates. Drinking too much at once or adding too much milk to tea and coffee can also affect blood sugar levels.

Diabetic patients: Be cautious if you fast for weight loss

Initially, fasting was used to reduce calorie intake by reducing half of the usual portion size. Although there is clinical evidence proving that this method can result in weight loss, it is difficult to follow a diet with such low calorie intake every day. Many patients eventually return to their normal diet, causing their weight to rebound. This gives rise to other fasting methods that are easier to implement and follow.

However, diabetic patients should only fast to lose weight when instructed by their doctors. If they are taking hypoglycaemic drugs or insulin, sudden fasting requires dosage adjustment. Plus, if patients have too little food intake, it can lead to malnutrition and reduced intake of protein, trace elements, vitamins and minerals, which can pose dangers to their bodies. If they consume insufficient carbohydrates, some patients, especially those with type 1 diabetes or those taking polysaccharide-based drugs, may develop ketosis which may lead to ketoacidosis. Therefore, patients must keep an eye on their weight loss methods.

In general, diabetes is a chronic disease that falls under the category of internal medicine and is a metabolic disease related to endocrinology. According to statistics from the Department of Health, diabetes ranks tenth among the top ten deadly diseases in Hong Kong, while kidney disease, stroke, and heart disease rank sixth, fourth, and third respectively. Diabetes indirectly increases the risk of heart disease, stroke, and kidney failure as well. Cancer is the top killer on the list, and diabetic patients also have a higher risk of developing cancer. When the blood sugar level is high, cancer cells have more sugar to survive. In addition, excessive insulin can stimulate the growth of cancer cells. It also triggers the imbalance of male and female sex hormones, increasing the risk of cancers such as colorectal cancer, pancreatic cancer, and female cancers like breast and ovarian cancer.

Dr Lam Tung (General Practitioner) (General Medicine)

In recent years, the number of overweight children in Hong Kong and worldwide has become alarmingly high. Dr Lam Tung pointed out that due to the trend of late marriage in recent years, many couples only plan to have one or two children, leading to a lower birth rate. Parents also tend to spoil their children and often use food or drinks as rewards, which often contain high sugar and fat. Coupled with insufficient exercise among children, this makes childhood obesity a global phenomenon.

Overweight children are at risk of developing type 2 diabetes, which can cause elevated blood sugar levels, high blood lipid levels, high blood pressure, joint pain, breathing difficulties, and even non-alcoholic fatty liver disease - all of which are common complications of childhood obesity.

If overweight children do not revise their lifestyle habits, they are likely to remain overweight when they grow up, and obese adults often develop higher insulin resistance. This makes insulin unable to control blood sugar levels properly, leading to a higher risk of developing type 2 diabetes. This is why childhood obesity can lead to the development of diabetes in adulthood.

Dr Fu Chiu Lai (Specialist in Cardiology)

Dr Fu Chiu Lai pointed out that there is a close relationship between diabetes and heart disease, with more than 30% of diabetic patients dying from cardiovascular disease. In addition, many complications of diabetes, such as diabetic retinopathy, diabetic nephropathy, and diabetic neuropathy, are all closely related to vascular disease caused by diabetes.

The "three highs" refer to diabetes, high blood pressure, and high blood lipid. People with the three highs are at risk of life-threatening conditions such as acute heart attack, stroke, and acute limb ischemia. Chronic diseases can lead to ischaemia and damage to various organs, such as chronic kidney failure, dementia, and peripheral vascular disease.

If diabetic patients, unfortunately, suffer from heart problems, the first step is to maintain a positive attitude, actively combat their illness, and then follow the doctor's instructions for medication, dietary restrictions, and exercise. They should schedule regular appointments and examinations to prevent acute illnesses and protect their safety.

To prevent diabetes and heart disease, it is important to follow the doctor's instructions to avoid unhealthy diets, take the right dose of medication at the right time, avoid sitting for long periods, and engage in regular physical activity. It is best to quit bad habits such as nightlife, smoking and drinking. Be sure to maintain a work-life balance, pay attention to your health all the time, and seek immediate medical attention if any symptoms develop suddenly.