by Dinethri Ramasundara APD AN
What are sterols and stanols?
Plant sterols and stanols are naturally occurring substances found in foods of plant origins such as vegetables, fruit, grains, nuts and seeds. Their molecular nature is very similar to cholesterol. When plant sterols and stanols are passed through our digestive system, they act as a decoy and gets absorbed into the blood. This prevents real cholesterol being absorbed in to the blood steam causing cholesterol to get excreted as waste. This mechanism is helpful if your cholesterol levels are high.
Latest research suggests sterols and stanols effectively decrease the low density cholesterol (LDL), commonly known as the “bad cholesterol” by 6-12% without lowering the “good cholesterol” (high density cholesterol – HDL). Plant sterols and stanols are safe to be used with cholesterol lowering medications.
Food industry has identified the importance of these functional foods in maintaining a healthy heart. Therefore have produced a range of fortified products from margarine spreads, cooking oil, dairy, juices to different breads and cereals to assist with the intake. In Australia it is found in margarine spreads, breakfast cereal, low-fat yoghurt and low-fat milk.
What is the safe amount to use?
Studies have found cholesterol-lowering effect increases with increase in dose. However effectiveness tapers off at 2 to 3 grams of plant stanols per day.
According to the Heart foundation, Australian regulations allow between 0.8 grams and 1.0 gram of plant sterols per serve; leaving you an allowance of 2 or 3 serves per day. Roughly a serve of fortified plant sterols are found in:
• 10 grams of margarine (about 2 teaspoons)
• 45 grams of cereal (about 1 cup or two biscuits)
• 250 millilitres low-fat milk (about 1 cup)
• 200 grams of reduced-fat yoghurt (1 small tub)
The use of plant sterols are not advised for children, pregnant and breastfeeding women as they have specific nutritional requirements and lowering blood cholesterol is not a priority for these groups.
Take home message: if you have high cholesterol, love your plant sterols and stanols!
References
Ras RT, Geleijnse JM and Trautwein EA 2014, LDL-cholesterol-lowering effect of plant sterols and stanols across different dose ranges: a meta-analysis of randomised controlled studies, British Journal of Nutrition, Access http://journals.cambridge.org/action/displayFulltext?type=6&fid=9250265&jid=BJN&volumeId=-1&issueId=-1&aid=9250264&fulltextType=RA&fileId=S0007114514000750
Marttinen M, Kosola M, Ovaskainen M-L, Mutanen M and Männistö S 2014, Plant sterol and stanol intake in Finland: a comparison between users and nonusers of plant sterol- and plant stanol-enriched foods, European Journal of Clinical Nutrition, Access http://www.nature.com/ejcn/journal/v68/n5/full/ejcn20143a.html
Kingberg S, Ellegard L, Johansson I, Jansson J-H, Hallmans G and Winkvist A 2013, Dietary Intake of Naturally Occurring Plant Sterols Is Related to a Lower Risk of a First Myocardial Infarction in Men but Not in Women in Northern Sweden, American Society for Nutrition Access http://jn.nutrition.org/content/143/10/1630.abstract?sid=86638822-9be7-43f3-9e86-055c1948130c
Heart Foundation Australia Access http://www.heartfoundation.org.au/SiteCollectionDocuments/Dietary-fats-summary-evidence.pdf
http://www.heartfoundation.org.au/SiteCollectionDocuments/Stanols-QA-General.pdf
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