Stanol ester
Stanol esters is a heterogeneous group of chemical compounds known to reduce the level of low-density lipoprotein (LDL) cholesterol in blood when ingested,[1] though to a much lesser degree than prescription drugs such as statins.[2] The starting material is phytosterols from plants. These are first hydrogenated to give a plant stanol which is then esterified with a mixture of fatty acids also derived from plants. Plant stanol esters are found naturally occurring in small quantities in fruits, vegetables, nuts, seeds, cereals, legumes, and vegetable oils.
Stanol ester is often added to rapeseed oil-based margarine or other foods for its health benefits. Studies have indicated that consumption of about 2-3 grams per day provides a reduction in LDL cholesterol of about 10-15%.[3]
The compound itself passes through the
Sterol esters can also be used for the same purpose. These compounds have the same effect to LDL, but they are partially absorbed by the body. The effects of higher serum plant sterol levels are so far not completely understood.
Plant stanols in nature
Plant sterols are cholesterol-like molecules found in all plant foods, with the highest concentrations occurring in vegetable oils. Plant sterols are plant equivalents of cholesterol and have a very similar molecular structure. According to their structure, they can be divided into sterols and stanols, stanols being a saturated subgroup of sterols.[citation needed]
Plant stanols in human nutrition
Plant stanols are present in small amounts in human diet. Their main sources are
Following evidence from toxicological studies and numerous
Structure and properties
Stanol esters are a saturated subgroup of sterol esters. Plant stanol esters in Benecol products are fatty acid esters of plant sterols. The sterol part of the molecule is sitostanol or campestanol while the fatty acid residue originates from different vegetable oils.
Plant stanol esters have the following physical properties:
- Fat-like with a waxy texture
- Creamy white colour in the solid form
- Viscous clear liquid with a bright yellow colour, bland odour and taste
- Insoluble in water and soluble in fat (hydrophobic)
- Viscosity higher than that of the triglyceride oil with the same fatty acid composition.
These physical properties can be tailored by changing the fatty acid composition. In different technological applications of Benecol products, the fatty acid part is selected so that the melting properties, texture and other characteristics of the plant stanol ester closely resemble the properties of the fat it replaces.
Oxidative and processing stability
Under normal storage and food preparation conditions, plant stanol esters are very stable because they are more resistant to
Using plant stanol esters in food applications instead of conventional fats does not decrease the shelf life of the end product. As is the case for all fats and oils, stanol esters should be protected from heat, air and light to prevent oxidation. If long-term storage is required, plant stanol esters are typically refrigerated in solid form. Furthermore, the usual
Lowering cholesterol
Esterified plant stanols have been proven to reduce
Dual effect of plant stanols
Plant stanols reduce both cholesterol and plant sterol levels in serum. This may be of importance since elevated plant sterol concentrations have been identified as an independent
Mutations in these transporter proteins lead to a rare congenital disease called sitosterolaemia, which is characterised by:
- severely elevated serum plant sterol concentrations,
- normal to moderately increased serum cholesterol concentrations, and
- a high risk of developing CHD at a very early age.
It was recently shown that polymorphisms in the ABCG5 and ABCG8 genes contribute to modifying serum plant sterol levels in healthy, non-sitosterolaemic individuals. Furthermore, several
Cholesterol absorption
The molecular mode of actions of stanols has been described in several preclinical and
- Step 1: bile acids. Stanols displace cholesterol from these micelles so that less cholesterol is absorbed. Stanols need to be taken as part of a meal in order to be incorporated in the micelles.
- Step 2: In vitro studies have shown that stanols activate LXR alpha, LXR beta and ABCA1 intestinal lumen. Only stanols have been proven to retain their efficacy in long-term use, most likely due to the minimal absorption of stanols, and consequently their lack of effect on bile acid metabolism.
As a consequence of the reduced absorption of cholesterol, the absorption of fat-soluble components other than cholesterol, such as
The results of randomised, placebo-controlled trials on the effects of plant sterols or stanols on fat-soluble vitamins and antioxidants were summarised in 2003.[10] Significant reductions were only seen in clinical trials for hydrocarbon carotenoids. These reductions are probably caused by reduced absorption and lower plasma concentrations of the carrier, LDL.
After correcting for cholesterol levels, only the reduction in the
See also
References
- ^ PMID 12911045.
- PMID 21296266.
- PMID 10573535. Retrieved 10 April 2015.
- ^ PMID 19158117.
- PMID 21257611.
- S2CID 22398350.
- ^ European Commission, Scientific Committee on Foods, General View on the Long-Term Effects of the Intake of Elevated Levels of Phytosterols from Multiple Dietary Sources, with Particular Attention to the Effects on α-Carotene, 26 September 2002.
- PMID 10602355.
- PMID 11756063.
- .
- PMID 12489060.
- ^ Assmann G; et al. (2003). "Elevation in Plasma Sitosterol Concentration Is Associated with an Increased Risk for Coronary Events in the PROCAM Study". Circulation. 108 (Suppl. IV–730): 3300.
Further reading
- Weingärtner O, et al. (2009). "Controversial role of plant sterol esters in the management of hypercholesterolaemia". Eur Heart J. 30 (4): 404–9. PMID 19158117.
- Weingartner, O.; Ulrich, C.; Lutjohann, D.; Ismail, K.; Schirmer, S. H.; Vanmierlo, T.; Bohm, M.; Laufs, U. (2011). "Differential effects on inhibition of cholesterol absorption by plant stanol and plant sterol esters in apoE-/- mice". Cardiovascular Research. 90 (3): 484–92. PMID 21257611.
External links
- American Heart Association
- American Dietetic Association
- Benecol products and research data
- Key Clinical Trials
- The Official International Site of Benecol
- Lichtenstein, A. H.; Deckelbaum, R. J. (2001). "Stanol/Sterol Ester-Containing Foods and Blood Cholesterol Levels : A Statement for Healthcare Professionals from the Nutrition Committee of the Council on Nutrition, Physical Activity, and Metabolism of the American Heart Association". Circulation. 103 (8): 1177–9. PMID 11222485.