Total Phytosterols
Also known as: Plant sterols, Plant stanols, Sitosterol, Campesterol, Stigmasterol, Phytosterols
Overview
Phytosterols are a group of naturally occurring plant sterols found in the cell membranes of various plants. They are chemically similar to cholesterol and are chiefly present in plant-based foods such as nuts, seeds, and vegetable oils. Primarily, phytosterols are utilized for their ability to lower blood cholesterol levels, particularly low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC). They function by interfering with the intestinal absorption of dietary cholesterol, leading to lower cholesterol levels in the bloodstream. With a strong body of high-quality evidence from numerous systematic reviews and meta-analyses, the cholesterol-lowering effects of phytosterols are well-established. Included forms are free phytosterols or their esters found in fortified foods and dietary supplements.
Benefits
Phytosterols significantly lower LDL-C concentrations; daily intake around 2.15 g reduces LDL-C by approximately 0.34 mmol/L and TC by 0.36 mmol/L. Systematic reviews indicate notable reductions in cholesterol levels for individuals with hypercholesterolemia, evidencing weighted mean differences of -0.37 mmol/L for TC and -0.34 mmol/L for LDL-C. The most marked benefits are seen in individuals with hypercholesterolemia, although results are also favorable in the general population. Clinical significance is implied, as these reductions correlate with decreased cardiovascular disease risk. Effects are generally observed within weeks of regular consumption, demonstrating substantial efficiency and safety.
How it works
Phytosterols work primarily by competing with cholesterol for absorption in the intestine, which reduces the amount of dietary cholesterol entering the bloodstream. By inhibiting the incorporation of cholesterol into micelles, phytosterols decrease overall cholesterol absorption. They interact predominantly with digestive processes and lipid metabolism, affecting cholesterol handling without being absorbed themselves in significant quantities.
Side effects
Phytosterols are generally recognized as safe, with no significant common side effects (>5%). Some individuals may experience mild gastrointestinal symptoms, such as bloating or gas, occurring infrequently (1-5%). Rare side effects (<1%) have not been thoroughly documented. There are no known significant drug interactions or contraindications for the general population. However, it is advised that pregnant or breastfeeding women consult healthcare providers prior to use, even though no specific contraindications exist for phytosterols in these populations.
Dosage
For effective cholesterol-lowering, a daily intake of 2-3 g of phytosterols is recommended. While some benefits may be observed with a minimum of 0.8 g to 1 g/day, optimal results generally manifest with consumption between 2 g and 3 g. It is best to take phytosterols with meals to enhance absorption in the presence of dietary fats. No upper limit of safety has been established, though doses exceeding 3 g/day do not yield additional benefits. They are available through fortified food products or as dietary supplements.
FAQs
How often should I consume phytosterols?
Daily consumption is advised, preferably with meals.
Are phytosterols safe for long-term use?
Yes, phytosterols are generally considered safe for long-term consumption.
When is the best time to take phytosterols?
They should be taken with meals to maximize their cholesterol-reducing effects.
How long does it take to see the effects?
The cholesterol-lowering effects are typically noticed within a few weeks.
Do phytosterols affect HDL-C or TG?
No, phytosterols do not significantly influence HDL-C or triglyceride levels.
Research Sources
- https://www.foodstandards.gov.au/sites/default/files/publications/Documents/EU%20health%20claims%20reviews/Systematic%20review%20phytosterols%20and%20cholesterol.pdf – This systematic review and meta-analysis included 84 trials encompassing 6805 participants and highlighted that a mean daily intake of 2.15 g phytosterol led to reductions in LDL-C and total cholesterol concentrations, establishing phytosterols' effectiveness in managing cholesterol levels.
- https://pubs.rsc.org/en/content/articlelanding/2023/fo/d2fo03663k – A systematic review specifically analyzing the effects of phytosterols in individuals with hypercholesterolemia found significant reductions in TC and LDL-C levels, with important implications for dietary recommendations in managing cholesterol.
- https://libguides.usc.edu/healthsciences/systematicreviews/databases – This resource provides comprehensive guidance on systematic reviews and emphasizes the relevance of evidence-based dietary supplements like phytosterols in lipid management.
- https://pubmed.ncbi.nlm.nih.gov/36891733/ – Gives insights into recent findings concerning phytosterols, affirming cholesterol-lowering effects and the need for consistent consumption for optimal results.
- https://www.nmcd-journal.com/article/S0939-4753(23)00161-8/pdf – This research discusses recent updates in systematic reviews about phytosterols, reflecting no new significant adverse effects while confirming their lipid-lowering efficacy.
