Margarines that claim to help lower cholesterol can now be found in any supermarket. Find out how they work and who can use them.
What are cholesterol-lowering margarines?
Cholesterol-lowering margarines are margarines enriched with naturally occurring substances called plant sterols or phytosterols. Plant sterols have been shown to lower blood cholesterol levels in people taking them correctly. Plant sterols occur naturally in seeds, nuts, some vegetable oils, legumes and some vegetables, but the quantities are usually too small to have a major effect on lowering cholesterol by eating these foods alone.
How do they work?
Plant sterols have a similar structure to cholesterol, and early research indicated they compete with cholesterol for absorption in the small intestine. Further research into their mechanism is continuing, but ultimately plant sterols reduce the amount of cholesterol absorbed from the small intestine into the bloodstream and so this unabsorbed cholesterol passes out of the body.
How much can they reduce cholesterol?
Margarines enriched with plant sterols can lower levels of so-called bad cholesterol (LDL-cholesterol) by up to 10 per cent when taken regularly for 3 weeks or more and according to instructions.
They are designed to be used in conjunction with other dietary and lifestyle changes and medicines prescribed by your doctor, not as the only form of treatment.
How much do I need to take?
The Heart Foundation recommends eating 2-3 grams of plant sterols a day, from plant-sterol enriched foods. This equates to about 2-3 serves of margarine a day. A serve being about 2 teaspoons. As well as margarine, there are also cereals, yoghurt and milk products enriched with plant sterols to reduce cholesterol.
There is no added benefit to eating any more than the recommended amount – it will not reduce your cholesterol further.
Are they safe?
There has been no evidence of any safety concerns around these plant sterol products. However, no long-term studies have been reported and they have been shown to lower levels of carotenoids (brightly coloured compounds in fruits and vegetables) in the body, which may increase risk of heart disease. To avoid this, people using plant sterol enriched products should make sure their diet is high in fruits and vegetables. You can do this by consuming an extra serve of fruit or vegetables, and including at least one rich in carotenoids. Examples of foods high in carotenoids are: carrots; pumpkin; orange sweet potato; spinach; broccoli; apricots; mangoes; tomatoes and rockmelon.
Who can take them?
Plant sterol enriched margarines are not recommended for pregnant or lactating women, or for children.
What if I take a statin or other cholesterol-lowering medicine?
Plant sterol enriched foods cannot replace the medicines prescribed by your doctor, but they can be taken at the same time as statins or other cholesterol-lowering medicines and they will have an additive effect on lowering cholesterol. If you have any doubts or questions, ask your doctor or pharmacist and they will be able to advise you.