Meta-analysis links sesame to modest cholesterol reductions in adults

A systematic review and meta-analysis of 13 randomized controlled trials involving 690 adults found that consuming sesame seeds, sesame oil or isolated sesamin was associated with modest reductions in total and low-density lipoprotein cholesterol, but no significant change in triglycerides or high-density lipoprotein cholesterol. Across the trials, sesame lowered total cholesterol by an average of 11.65 milligrams per deciliter and LDL cholesterol by 9.14 milligrams per deciliter relative to the control treatments. The evidence was rated as moderate certainty for the LDL-cholesterol reduction but only low certainty for total cholesterol.

The trials were generally small, short and geographically concentrated, and none measured cardiovascular events, so the results concern blood lipid markers rather than proven clinical protection against heart disease or stroke. The analysis, registered prospectively and conducted in line with systematic-review guidance, searched five electronic databases from their inception through March 6, 2026, and also examined references and citations. Eleven included studies used parallel-group designs and two used crossover designs.

The participants included adults with type 2 diabetes, hyperlipidemia, hemodialysis, knee osteoarthritis, rheumatoid arthritis or non-alcoholic fatty liver disease, as well as healthy postmenopausal women, overweight or obese adults with at least one metabolic risk factor, and otherwise healthy adults with slightly elevated LDL cholesterol. Interventions included whole or ground sesame seeds, sesame oil and 200-milligram sesamin capsules, while controls ranged from matched placebos and usual diets to sunflower oil. The pooled reduction in total cholesterol was statistically significant, with a mean difference of −11.65 milligrams per deciliter and a 95% confidence interval from −18.73 to −4.57.

Statistical heterogeneity was moderate at 57.7%. The result was significant among trials using sesame oil or seed, which showed a reduction of 10.86 milligrams per deciliter, but not in the two sesamin trials, whose point estimate was larger but highly uncertain. Both healthy participants and those with medical conditions showed significant reductions, and formal tests did not establish that the two groups differed.

The total-cholesterol estimate remained statistically significant when individual studies were removed in sensitivity analyses, although excluding one high-risk-of-bias trial attenuated it to 8.21 milligrams per deciliter. LDL cholesterol produced the review’s most consistent lipid finding. Sesame-based interventions led to a pooled reduction of 9.14 milligrams per deciliter, with a 95% confidence interval of −14.40 to −3.89 and moderate heterogeneity of 44.0%.

The estimate remained statistically significant after any single trial was omitted and remained significant after two studies using sunflower oil as the comparator were excluded. Subgroup estimates were similar in healthy participants and those with medical conditions. As with total cholesterol, statistically significant reductions were confined to interventions lasting at least eight weeks, but the formal difference between shorter and longer trials did not meet the threshold for a definitive subgroup effect.

Triglycerides did not change significantly overall. The pooled difference was −14.15 milligrams per deciliter, but its 95% confidence interval extended from −29.04 to 0.74 and heterogeneity was substantial at 63.4%. The result was sensitive to the removal of individual studies, illustrating the limited stability of the pooled estimate.

Trials involving participants with medical conditions showed a significant reduction of 22.79 milligrams per deciliter, whereas the three estimates in healthy participants indicated a small, nonsignificant change in the opposite direction. Because the difference between groups was borderline, the analysis included only three healthy estimates, and the groups also differed in baseline triglycerides and intervention characteristics, the reviewers treated this pattern as hypothesis-generating rather than proof of a distinct response by health status. Sesame also had no significant overall effect on HDL cholesterol, with a mean difference of 0.38 milligrams per deciliter and a 95% confidence interval of −1.62 to 2.38.

A small increase appeared in trials lasting fewer than eight weeks, while longer trials showed no change. Although the formal test for this duration difference was nominally significant, the review treated it cautiously because the analysis included multiple subgroup comparisons across four lipid outcomes, increasing the possibility of chance findings. The investigators also found no consistent concentration-response relationship for total or LDL cholesterol.

Delivered lignan content was quantified in only six of the 13 trials, while differences in preparation, dose, duration, participant health and product composition prevented formal dose-response modelling. Using the GRADE framework, the reviewers rated the evidence as moderate certainty for the LDL-cholesterol reduction, low certainty for the total-cholesterol reduction, very low certainty for triglycerides and moderate certainty for HDL cholesterol. The LDL result was downgraded only for imprecision because its confidence interval did not extend beyond the prespecified clinically important difference of 4 milligrams per deciliter.

Evidence for total cholesterol was downgraded for risk of bias and imprecision, while the triglyceride evidence was downgraded for risk of bias, inconsistency and imprecision. Risk-of-bias assessments classified three trials as low risk, eight as raising some concerns and two as high risk. Concerns arose mainly from the randomization process and missing outcome data.

The investigators examined funnel plots and used Egger’s regression tests to assess possible small-study effects. Neither analysis provided evidence of such effects for any of the four lipid outcomes, and the pooled total- and LDL-cholesterol estimates remained statistically significant in leave-one-out analyses. These checks do not prove that publication bias was absent because both approaches have limited power with only 12 or 13 estimates.

The sensitivity analyses also showed that the triglyceride result could become significant after omitting either of two particular studies, while the overall HDL-cholesterol estimate remained nonsignificant regardless of which single study was removed. Excluding the two sunflower-oil comparator trials did not materially alter the total-cholesterol result and only slightly attenuated the LDL-cholesterol reduction. Laboratory and animal experiments offer possible explanations for the cholesterol findings but do not establish clinical effects in people.

Sesamin, a major sesame lignan, has been reported in preclinical work to inhibit cholesterol synthesis, influence intestinal absorption and promote cholesterol efflux. These proposed pathways are consistent with the possibility that sustained exposure could influence lipid metabolism, but many remain supported mainly by cell or animal evidence. The review used only human randomized evidence for its pooled results, and no included trial measured cardiovascular events such as myocardial infarction or stroke.

The findings therefore concern surrogate lipid markers, not proof that sesame prevents cardiovascular disease or provides an alternative to established lipid-lowering treatment. Several limitations constrain the conclusions. The evidence base contained only 13 trials and 690 participants, and individual studies ranged from 30 to 103 people.

Most interventions lasted five to 12 weeks, none exceeded 12 weeks, and only two directly tested purified sesamin. Nine studies were conducted in Iran, two in Japan and one each in Taiwan and Australia, limiting generalizability to other populations and dietary patterns. Seven trials used matched placebos, four used no sesame without a specific placebo, and two used sunflower oil, meaning some estimates reflected the relative effects of sesame and another dietary oil.

Most studies did not quantify the actual lignan content of their preparations, and two low-risk sesame-oil trials were funded by a sesame manufacturer. Long-term efficacy, safety, optimal dose and the effect of different processing methods remain uncertain. Overall, the review identifies sesame as a potentially useful dietary adjunct with a selective, modest effect on atherogenic cholesterol rather than a comprehensive treatment for dyslipidemia.

The strongest result was an average LDL-cholesterol reduction of about 9 milligrams per deciliter, supported by moderate-certainty evidence, while total cholesterol fell by about 12 milligrams per deciliter on lower-certainty evidence. There was no demonstrated overall benefit for triglycerides or HDL cholesterol, and the apparent advantages of longer treatment or purified sesamin remain uncertain. The authors call for larger, longer, low-risk-of-bias trials that measure bioactive compound content, compare seeds, oil and sesamin directly, recruit populations beyond the current geographic concentration and evaluate clinical cardiovascular endpoints.

Subject of Research: Effects of sesame seeds, sesame oil and sesamin on serum lipid profiles in adults

Article Title: Effects of Sesame ( Sesamum indicum L.) and Its Lignan Sesamin on the Serum Lipid Profile: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Article References: Inthachat, W., Chupeerach, C., Trachootham, D., & Temviriyanukul, P. (2026). Effects of Sesame (Sesamum indicum L.) and Its Lignan Sesamin on the Serum Lipid Profile: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Journal of Agriculture and Food Research, Article 103379. https://doi.org/10.1016/j.jafr.2026.103379

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103379

Keywords: sesame, sesamin, cholesterol, LDL cholesterol, triglycerides, HDL cholesterol, randomized trials, meta-analysis, lipid profile, dietary interventions, Effects, Sesamum