Side effects of plant sterols and stanols
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Plant Sterols and Stanols: Common Side Effects and Safety Concerns
Plant sterols and stanols are widely used in functional foods to help lower LDL cholesterol levels, but their safety and potential side effects have been closely studied. Most research shows that these compounds are generally safe for most people when consumed at recommended doses, but some effects and concerns have been noted.
Changes in Blood Sterol Levels
Regular consumption of plant sterol-enriched foods can increase blood levels of plant sterols, such as sitosterol and campesterol, though these increases are much lower than those seen in rare genetic conditions like sitosterolemia, where adverse health effects are more likely. Stanol-enriched foods do not cause the same increase in blood sterol levels. The health impact of these moderate increases in plant sterol levels is still debated, and more long-term monitoring is needed to fully understand any potential risks 1510.
Effects on Fat-Soluble Vitamins and Carotenoids
Plant sterols and stanols can slightly reduce blood levels of some fat-soluble vitamins and carotenoids, especially beta-carotene. However, these reductions are usually small and not considered clinically significant, as most levels remain within the normal range. Vitamins A and D, as well as other carotenoids and vitamin E, are generally not affected in a meaningful way 12810.
Gastrointestinal and Other Side Effects
Human studies have found that side effects from plant sterols and stanols are similar to those seen with placebo, meaning they are rare and mild. No significant harmful side effects have been reported in the general population at recommended intake levels 210.
Effects on Hormones and Other Body Systems
There is no evidence that plant sterols or stanols, at typical dietary doses, have negative effects on sex hormone metabolism or other hormone systems in humans. Some animal studies using very high doses have shown effects, but these are not relevant to normal human consumption .
Impact on Blood Pressure, Endothelial Function, and Inflammation
Research shows little to no effect of plant sterol or stanol supplementation on blood pressure, endothelial function, or markers of inflammation and oxidative stress, even in people taking statins. These findings suggest that plant sterols and stanols do not have significant side effects on these aspects of cardiovascular health 367.
Rare and Long-Term Risks
While current evidence supports the safety of plant sterols and stanols for most people, experts recommend ongoing monitoring, especially as more people consume a wider variety of enriched foods. This is to ensure that rare or long-term adverse effects, if any, are detected early 12410.
Conclusion
Plant sterols and stanols are effective at lowering LDL cholesterol and are generally safe for most people when consumed as recommended. The main side effects are small increases in blood plant sterol levels and slight reductions in some carotenoids, neither of which are currently considered a major health concern. Ongoing surveillance is important to monitor for any rare or long-term side effects as their use becomes more widespread.
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