Eat to beat cholesterol

Some years back, a friend of mine was shocked to learn during an annual body check-up that her cholesterol levels were way above the recommended levels for an average adult. She was in her late 20s then.

On hindsight, her shockingly high blood cholesterol wasn't surprising. Despite her svelte figure, her lifestyle - a daily pint of high-fat ice-cream coupled with a non-existent exercise routine - was hardly cholesterol-friendly.

We all know that certain foods such as ice-cream, organ meats such as liver and intestines, egg yolks and shellfish can raise our cholesterol levels. The good news is, a few tweaks to your diet may be able to do the reverse.

According to Dr Chin Chee Tang, a consultant at the department of cardiology at the National Heart Centre Singapore (NHCS), some cholesterol is required for life - it is an essential building block of cell membranes in the body. In most people, the liver is able to make most of the cholesterol the body needs.

Overindulging in fried chicken wings and cakes, however, can be devastating for your cholesterol levels.

"When we eat foods rich in saturated fats, the normal digestive process leads to the absorption of cholesterol in the blood stream," said Dr Chin.

The good and the bad

In particular, Dr Chin said high levels of low-density lipoprotein (LDL) cholesterol, commonly known as bad cholesterol, is strongly associated with early or more rapid development of atherosclerosis, the narrowing of blood vessels in the body.

"Atherosclerosis in turn leads to other conditions such as heart disease, stroke, kidney failure or poor circulation," he explained.

On the association of high cholesterol with heart conditions, Dr Chin cited recent data from the National Registry of Diseases Office: It was reported that among Singaporeans who had a heart attack from 2007 to 2008, high cholesterol was present in 56 per cent of these patients.

To keep your blood cholesterol levels healthy, it is important to keep your saturated fat and trans fat intake low, according to Benjamin Lee, a nutritionist at Health Promotion Board's adult health division.

"Both types of fat are able to increase LDL cholesterol levels. Trans fat also reduces the level of high-density lipoprotein (HDL) cholesterol - also known as good cholesterol - and has more impact on blood cholesterol levels than cholesterol from food," said Lee.

In Singapore, Lee noted that most of our intake of saturated fat come from dishes prepared using coconut milk or cream, as well as from palm oil, which is usually labelled as "vegetable oil".

Trans fat is typically found in pastries and cakes made with vegetable shortening, commercially-prepared deep fried food and processed products containing partially-hydrogenated oil, he added.

"To be safe, limit your cholesterol intake to less than 300mg per day. Avoid consuming organ meat and shellfish more than twice a week, and have no more than four egg yolks per week," he advised.

But relying on diet isn't enough. Dr Chin urged smokers to also stub out and recommended at least 30 minutes of moderate intensity physical activity at least four times a week.

Eat your way to a healthier cholesterol level

Not all foods are equal. Studies have found that certain foods - such as salmon, walnuts, oatmeal and some veggies - can help control your cholesterol. Nehal Kamdar, senior dietitian at Raffles Hospital, suggests including these four heart-friendly foods into your diet.

1. Fatty fish

Oily fish such as salmon, mackerel and sardines are rich sources of omega-3 fatty acids, which help to lower blood fats linked to heart disease. According to Kamdar, omega-3 fatty acid prevent blood clots by making platelets less likely to clump together and stick to artery walls. It also makes blood vessels less likely to constrict. She suggested eating at least two servings of such fish twice a week. Just be sure to cook your fish using healthier methods such as steaming and baking to avoid unhealthy fats.

2. Go nuts

Nuts such as walnuts and almonds are high in polyunsaturated fatty acids, which keep blood vessels healthy. In particular, walnuts are one of the best plant sources of protein as they are packed with vitamins, fibre and antioxidants, said Kamdar. But be sure to stick to just 30g (a fistful) each day, and avoid nuts that are salted or coated with sugar. Besides nuts, Kamdar recommended including one to two tablespoonfuls of ground flax seed into your food each day to help lower bad cholesterol. However, Dr Chin Chee Tang of NHCS added that while some studies have shown that flax seed and peanuts may help lower cholesterol levels, further research is required to confirm their cholesterol-lowering benefits.

3. Soy good

Soy protein such as soy beans, tofu, soya milk and tempeh (fermented soybeans) may be able to keep cholesterol levels in check. "Rich in omega-3 fatty acids, protein, vitamin and minerals, soy protein is a good alternative to red meat as it is lower in fat and higher in fibre," said Kamdar. She added that those with high cholesterol may be able to lower their cholesterol levels when soy protein is eaten as part of a healthy low-fat diet.

4. A bowl of oatmeal a day keeps high cholesterol away

Eating oats not only keeps your bowel movements regular, it may even help lower cholesterol levels, and reduce risks of heart disease and diabetes, said Kamdar. Diabetes is another risk factor for heart disease. She added that oatmeal also fills a person up for a longer time, so he or she will not tempted by unhealthy snacks that may raise cholesterol levels.

What is considered a healthy level of cholesterol?

In general, the lower the total and LDL cholesterol levels, the lower your risk of getting medical problems associated with atherosclerosis, said Dr Chin Chee Tang of National Heart Centre Singapore.

What is considered a 'healthy' cholesterol level depends also on the presence of other medical conditions, he said.

"For an otherwise healthy individual with no other significant medical problems, a total cholesterol level greater than 6.2mmol/L (or 240mg/dL) is considered high and undesirable. Similarly, people with no significant medical problems should aim to have a LDL cholesterol level of no greater than 3.4mmol/L (130mg/dL)."

For patients who have medical problems such as a previous heart attack or stroke, the recommended levels are even lower.