Plant Sterols / Phytosterols
Research reviewed: Up until 03/2026
Plant Sterols / Phytosterols (Phytosterols (beta-sitosterol, campesterol, stigmasterol, stanols)) is a dietary supplement with 12 published peer-reviewed studies involving 885 participants, researched for LDL Cholesterol Reduction, Cholesterol & Immune Health.
Evidence at a Glance
Strength is scored by study design, sample size, study type, and outcomes
LDL Cholesterol Reduction
ModerateCholesterol & Immune Health
ModerateResearch Visualised
Visual breakdown of the clinical data.
Study Quality Breakdown
What types of studies were conducted
Participants Per Study
Larger samples = more reliable results
Research Timeline
When the studies were published
All Studies
Detailed breakdown of each trial. Click to expand.
LDL Cholesterol Reduction
To determine the dose-response relationship for LDL-C lowering by plant sterols and stanols.
Study Type
Meta-analysis of randomised controlled trials
Purpose
To determine the dose-response relationship for LDL-C lowering by plant sterols and stanols.
Dose
0.5–3 g/day plant sterols or stanols
Participants
Pooled from >80 RCTs
Duration
4–26 weeks
Results
Plant sterols/stanols produced dose-dependent LDL-C reductions of 8–12% at 2–3 g/day. Effect plateaued beyond 3 g/day. HDL-C and TG largely unaffected. Results consistent across food matrices.
How They Measured It
Pooled LDL-C change across dose ranges in RCTs
To quantify the LDL-C-lowering effect of plant sterols/stanols enriched foods vs control.
Study Type
Meta-analysis of randomised controlled trials
Purpose
To quantify the LDL-C-lowering effect of plant sterols/stanols enriched foods vs control.
Dose
Various (mean ~2 g/day)
Participants
84 RCTs included
Duration
Various
Results
Phytosterols reduced LDL-C by mean ~10% (0.34 mmol/L). Greater reductions with higher baseline LDL-C and when consumed at mealtimes with fat. Sterols and stanols showed comparable efficacy.
How They Measured It
Pooled mean difference in LDL-C
To evaluate the effects of phytosterols on cardiovascular risk factors in patients with hyperlipidaemia.
Study Type
Systematic review and meta-analysis
Purpose
To evaluate the effects of phytosterols on cardiovascular risk factors in patients with hyperlipidaemia.
Dose
1–3 g/day
Participants
Multiple RCTs
Duration
Various
Results
Phytosterols significantly reduced LDL-C and TC. Modest TG reductions in subgroup analyses. Effects on blood pressure and inflammation neutral. Results support phytosterols as adjunct therapy for dyslipidaemia.
How They Measured It
LDL-C, TC, TG, HDL-C, CRP, blood pressure meta-regression
To assess LDL-C-lowering efficacy of plant stanol ester-enriched margarine in hypercholesterolaemic adults.
Study Type
Randomised, double-blind, placebo-controlled crossover
Purpose
To assess LDL-C-lowering efficacy of plant stanol ester-enriched margarine in hypercholesterolaemic adults.
Dose
2.5 g/day plant stanols as stanol esters in margarine
Participants
153 mildly hypercholesterolaemic adults
Duration
8 weeks per arm
Results
Plant stanol ester margarine reduced LDL-C by 10.2% and TC by 7.8% vs control margarine. No significant effect on HDL-C or TG. Supports EFSA cholesterol-lowering health claim for phytosterols.
How They Measured It
Fasting serum lipid panel at crossover periods
To evaluate plant sterols combined with statin therapy on LDL-C in hypercholesterolaemic patients.
Study Type
Randomised, double-blind, placebo-controlled
Purpose
To evaluate plant sterols combined with statin therapy on LDL-C in hypercholesterolaemic patients.
Dose
2 g/day plant sterols added to existing statin therapy
Participants
232 statin-treated patients with residual hypercholesterolaemia
Duration
12 weeks
Results
Addition of plant sterols to statin therapy further reduced LDL-C by 10% beyond statin alone (p<0.001). Well tolerated with no increase in adverse events.
How They Measured It
Serum LDL-C, TC at 6 and 12 weeks
To study whether plant sterols derived from rice bran oil reduce plasma lipids in mildly hypercholesterolaemic individuals.
Study Type
Randomised, placebo-controlled
Purpose
To study whether plant sterols derived from rice bran oil reduce plasma lipids in mildly hypercholesterolaemic individuals.
Dose
2 g/day plant sterols from rice bran oil spread
Participants
88 mildly hypercholesterolaemic adults
Duration
8 weeks
Results
Plant sterol spread significantly reduced LDL-C by 9.4% and TC by 7.3% vs control. Apolipoprotein B also reduced. Rice bran oil-derived sterols were as effective as other sterol sources.
How They Measured It
Serum lipids and apolipoproteins at 4 and 8 weeks
To review the mechanism of cholesterol absorption inhibition by phytosterols and clinical implications.
Study Type
Review of mechanism and clinical evidence
Purpose
To review the mechanism of cholesterol absorption inhibition by phytosterols and clinical implications.
Dose
2 g/day (recommended therapeutic range)
Participants
Review of available evidence
Duration
Various
Results
Phytosterols compete with dietary and biliary cholesterol for micellar incorporation and NPC1L1-mediated intestinal absorption. Clinical trials consistently show 9–14% LDL-C reduction at 2–3 g/day. Effects are additive to statin therapy.
How They Measured It
Mechanistic review plus clinical data summary
To assess phytosterol supplementation on LDL-C and cardiovascular biomarkers in high-risk subjects.
Study Type
Randomised controlled trial
Purpose
To assess phytosterol supplementation on LDL-C and cardiovascular biomarkers in high-risk subjects.
Dose
2 g/day phytosterol ester yoghurt drink
Participants
180 adults with moderate cardiovascular risk
Duration
12 weeks
Results
Phytosterol-enriched yoghurt drink significantly reduced LDL-C by 9.7% and apoB by 7.4% vs control. TC/HDL ratio improved. CRP unchanged.
How They Measured It
LDL-C, apoB, CRP, TC/HDL ratio
To evaluate phytosterol effects in hyperlipidaemic vs normolipidaemic subjects.
Study Type
Systematic review and meta-analysis
Purpose
To evaluate phytosterol effects in hyperlipidaemic vs normolipidaemic subjects.
Dose
1–4 g/day
Participants
Meta-analysis of multiple RCTs
Duration
Various
Results
LDL-C reductions were greater in hyperlipidaemic subjects (−12.4%) vs normolipidaemic (−7.8%). TC consistently reduced across all subgroups. Phytosterols are most clinically impactful in those with elevated baseline cholesterol.
How They Measured It
LDL-C, TC, HDL-C, TG compared between subject groups
To investigate phytosterol supplementation in patients with familial hypercholesterolaemia on maximal lipid-lowering therapy.
Study Type
Randomised, double-blind, placebo-controlled
Purpose
To investigate phytosterol supplementation in patients with familial hypercholesterolaemia on maximal lipid-lowering therapy.
Dose
2 g/day plant sterols
Participants
68 patients with heterozygous familial hypercholesterolaemia
Duration
16 weeks
Results
Plant sterols provided an additional 6% LDL-C reduction (p=0.04) beyond maximal therapy. Results support plant sterols as beneficial addition to combination pharmacotherapy in FH.
How They Measured It
LDL-C, TC, sitosterol and campesterol absorption markers
Cholesterol & Immune Health
To evaluate phytosterols and phospholipids combination on lipid metabolism and oxidative stress.
Study Type
Randomized Controlled Trial
Purpose
To evaluate phytosterols and phospholipids combination on lipid metabolism and oxidative stress.
Dose
Phytosterols combined with phospholipids supplement
Participants
Adults with mild to moderate hypercholesterolemia
Duration
8 weeks
Results
Phytosterols combined with phospholipids synergistically improved lipid metabolism and reduced oxidative stress compared to either alone.
How They Measured It
LDL cholesterol, HDL, total cholesterol, triglycerides, oxidative stress markers
To evaluate the effects of three different daily plant stanol ester intakes on influenza vaccination responses in older adults.
Study Type
Randomized, Double-Blind, Placebo-Controlled
Purpose
To evaluate the effects of three different daily plant stanol ester intakes on influenza vaccination responses in older adults.
Dose
Plant stanols 2 g, 3 g, or 4 g daily
Participants
Older adults receiving influenza vaccination
Duration
12 weeks
Results
Plant stanol supplementation at 3 g/day significantly improved influenza vaccine antibody responses in older adults compared to placebo.
How They Measured It
Antibody responses to influenza vaccine, immune cell populations
Frequently Asked Questions
Common questions about Plant Sterols / Phytosterols research
There are currently 12 peer-reviewed studies on Plant Sterols / Phytosterols (Phytosterols (beta-sitosterol, campesterol, stigmasterol, stanols)), involving 885 total participants. Research covers LDL cholesterol reduction, Total cholesterol lowering, Cardiovascular risk reduction and 1 more areas. The overall evidence strength is rated as Strong.
The evidence is currently rated as "Strong Evidence". This rating is based on study design quality (randomisation, blinding, placebo controls), sample sizes, study types (7 human studies), and reported outcomes.
Plant Sterols / Phytosterols has been researched for: LDL cholesterol reduction, Total cholesterol lowering, Cardiovascular risk reduction, Cholesterol absorption inhibition. Each area has its own body of evidence which you can explore in the study breakdowns above.
Yes, 7 out of 12 studies are human trials. Human trials carry more weight in our evidence scoring system.
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