The numbers do not look good.

As of 2010, more than half of Singapore's adult population between 18 and 69 years old have high cholesterol, four in 10 are overweight or obese, a quarter have pre-diabetes or diabetes and about one in five has hypertension.

Doctors and public health officials suspect that many people are yet to be diagnosed and, among those who have been diagnosed, many are not doing enough (if anything) to bring these conditions under control, said Dr Lim Su Lin, chief dietitian at the National University Hospital.

The sad thing is that because of the high rate of chronic diseases in the community, people think that it is normal as their friends also have the same problem, she said.

The burden of chronic diseases lies not only in bringing the physiological abnormalities (such as being overweight and having high blood sugar and high blood pressure) back to normal.

Left untreated, the associated complications may lead to disability, escalating healthcare costs and premature death, she said.

For instance, obesity is a risk factor for diabetes, heart disease, arthritis and stroke. Untreated and uncontrolled diabetes leads to coronary heart disease, kidney failure, blindness and limb amputation.

Chronic diseases are sometimes called lifestyle diseases.

A recent study found that unhealthy behaviour and lifestyles such as unhealthy eating, smoking, drinking too much alcohol and not exercising can shorten your life by as many as 12 years, she said.

If your chronic diseases are not controlled, you will likely suffer poor quality of health for 15 years before dying of complications of the diseases, she added. But do not just sit back and accept the inevitable.

There are positive steps you can take to prevent or manage these chronic diseases, one of which is to maintain a healthy lifestyle and weight.

Dr Lim gives some lifestyle tips on how to get there:

FOOD

Choose food that contains minimal amounts of unhealthy fats, such as trans fats and saturated fats.

Foods that are high in trans fats include those made with "partially hydrogenated oils" such as pastries, confectionaries, fried food, pizza and cookies.

Foods that are high in saturated fats include lard, fatty meat, cakes, fast food, pizza and full-fat dairy products.

However, your diet may include moderate amounts of healthy fats, such as polyunsaturated, monounsaturated and Omega-3 fats.

These should still be taken in moderation to prevent weight gain.

Limit your intake of sugar that is found in soft drinks, beverages with added sugar (such as coffee, tea, chocolate drink), processed fruit juices, sweets, cakes, desserts and pastries.

Choose wholegrain carbohydrates instead of refined carbohydrates. For example, choose wholegrain bread instead of white bread, and brown rice instead of white rice.

Choose fish, chicken without the skin, beans, tofu or lean meat for protein instead of fatty meat.

Choose foods that are prepared with healthier cooking methods. These include food that is steamed, grilled, baked, stewed, boiled or airfried instead of deepfried.

Include fruit and vegetables in your daily diet. And do not overeat - know when to stop.

EXERCISE

Include exercise or activities as part of your daily routine. It is recommended that you exercise about three times per week for 30 to 60 minutes each time so that it becomes a habit.

You can also incorporate activities into your daily routine by taking the stairs instead of the lift, parking further away from shops and walking there instead, and taking a quick walk during your lunch break or walking to work or home.

ALCOHOL

Avoid or drink alcohol in moderation. Take no more than one standard drink (one can of beer, half a glass of wine or one shot of hard liquor) for women and two standard drinks for men per day.

SMOKING

Do not smoke. It is associated with a variety of health risks, including heart or liver disease and many cancers.

Ng Wan Ching