Irish Heart Foundation dietitian Orna O’Brien explains the role of plant stanols and sterols in reducing cholesterol and reminds us that they are not miracle workers.

What are plant stanols and sterols?

Plant stanols and sterols are natural chemicals found in small amounts in some plant-based foods like vegetable oils, nuts, seeds, legumes, fruit, vegetables, and wholegrains. Studies show that, along with a healthy diet, eating foods that provide you with around 2 grams of plant stanols or sterols every day can reduce LDL cholesterol (the bad cholesterol) in our blood. However, the amount we find naturally in food is not enough to lower cholesterol. Because of this, food companies developed foods with plant sterols or stanols added to them, like yogurt drinks, fat spreads, milk, and yogurts.

How do plant stanols and sterols lower cholesterol?

Plant stanols and sterols are similar in size and shape to cholesterol, so they compete with cholesterol for absorption in our intestines. This means we absorb less cholesterol from food, which helps to lower total cholesterol and LDL cholesterol in our blood. Cholesterol also gets into the digestive tract from the liver and plant stanols or sterols help to reduce the amount of this type of cholesterol you re-absorb.

Plant stanols/sterols have no effect on HDL cholesterol (the good cholesterol) or triglycerides (another fat in our blood).

How effective are they at lowering cholesterol?

Eating 2g of plant stanols or sterols every day has been shown to be generally safe and effective at reducing cholesterol by 7.5 to 12 per cent in about three weeks. However, there is no long-term evidence to show that these products reduce your risk of having a heart attack or stroke. They are not miracle workers either, and you will still need to eat a healthy, balanced diet to get the best benefit.

Who can benefit from taking plant stanols and sterols?

People at risk of cardiovascular disease can benefit from taking plant stanols and sterols, especially people with high levels of LDL cholesterol, familial hypercholesterolaemia, or type two diabetes.

Who should avoid taking plant stanols and sterols?

Plant stanols and sterols are not recommended for pregnant or breastfeeding women or children under five because there is not enough information about their safety in these groups. There is no benefit to taking them if your cholesterol levels are normal.

Can I take plant stanols or sterols with cholesterol-lowering medications?

Plant stanols or sterols are not a replacement for any cholesterol-lowering medication.  If you have been prescribed medication to lower your cholesterol, you should inform your doctor before you start taking these products.

Food products with added stanols or sterols are safe for people taking cholesterol-lowering medication such as statins and fibrates. In fact, the effect of taking both can decrease non-HDL cholesterol levels significantly more than the 20 to 30 per cent reduction achieved by taking a statin alone because they work in different ways to reduce cholesterol.

Plant stanols and sterols are unlikely to have much effect if you are taking another type of cholesterol-lowering medicine, Ezetrol (Eztemibe) because they both work in a similar way.

How much do I need to get 2g of stanol or sterol?

If you decide to use a food product fortified with plant stanols or sterols, follow the instructions on the packaging. You need to take them every day in sufficient amounts to have an effect. It is important to eat the products with a meal so they mix and bind with the food you eat. If you stop using them, the potential benefit of lowered cholesterol will also stop.

You can achieve 2g per day of plant stanol or sterol by consuming:

• One plant stanol or sterol fortified mini yoghurt drink (one bottle) or one pot of yoghurt per day which contains all the 2g recommended OR
• Two to three portions of foods with at least 0.8g of added plant stanol or sterol per day such as:
• Two teaspoons (10g) fortified spread (enough for 1-2 slices of bread)
• One fortified yoghurt
• One glass (250ml) fortified milk
• These products can be expensive, but supermarkets’ own brands offer the benefits of the branded products often at a fraction of the cost.
• Stanols and sterols are also available in dietary supplements. They are generally as effective, but less popular than food-fortified products.
• There is no benefit in consuming more than the maximum recommended amount of 2-3g.

What other ways can I lower my cholesterol?

It is not essential to take plant stanols or sterols to help manage your cholesterol. They are not a substitute for a healthy diet or a replacement for cholesterol-lowering medication. To help lower your cholesterol, it is more important to make long-term changes to your diet and lifestyle.

Here are some ideas:

• Stop smoking
• Enjoy at least 30 minutes of moderate-intensity physical activity on most, if not all, days of the week
• Replace unhealthy fats (trans and saturated) with healthy ones (monounsaturated and polyunsaturated)
• Increase fibre by eating more fruit, vegetables, whole grains, and legumes
• Choose lean meat and poultry, lower-fat dairy products, fish (including oily fish), nuts, and plant-based proteins such as soy, beans, and lentils more often
• Limit alcohol to no more than 17 standard drinks per week (men) or no more than 11 standard drinks per week (women)
• Take cholesterol-lowering medication as advised if prescribed.