Benefits
Modest support for healthy blood pressure in people with elevated readings (meta-analysis)
A meta-analysis (7 trials) showed sesamin supplementation significantly reduced systolic blood pressure but did not affect diastolic BP, weight, HDL-c, or triglycerides. A separate trial found 4-week sesamin 60 mg/day reduced both systolic and diastolic BP in mildly hypertensive humans. The average systolic reduction in the meta-analysis was modest (a few mmHg), with no significant effect on diastolic pressure.
Lipid profile improvements
Meta-analysis showed sesamin supplementation significantly reduced total cholesterol and LDL-c, and sesame lignan reduced cholesterol in humans. Effect is more pronounced with elevated baseline cholesterol and less consistent in normocholesterolemic individuals. Sesame oil components may contribute additionally via gamma-tocopherol preservation.
20-HETE inhibition (vasoactive metabolite)
A crossover RCT in overweight subjects showed 25 g/day sesame for 5 weeks reduced plasma 20-HETE by 28% and urinary 20-HETE by 32% (P<0.001) via CYP4F2 inhibition. 20-HETE is implicated in blood pressure regulation, offering a plausible mechanism, though blood pressure itself was unchanged in this short trial. Although BP was unchanged in this short trial, 20-HETE reduction is a relevant downstream target.
Antioxidant capacity enhancement (vitamin E sparing)
Sesamin inhibits CYP4F2-mediated metabolism of α- and γ-tocopherol, preserving vitamin E levels and antioxidant capacity. Sesame seed/oil consumption reliably increases plasma γ-tocopherol — particularly relevant since γ-tocopherol has unique anti-inflammatory effects on RNS. Black sesame meal reduced MDA and increased GSH/total antioxidant capacity.
Mechanism of action
CYP4F2 inhibition (vitamin E preservation + 20-HETE reduction)
Sesamin selectively inhibits cytochrome P450 4F2 (IC50 ~1.9 μM) — the enzyme responsible for both ω-hydroxylation of α/γ-tocopherol (degrading vitamin E) and synthesis of 20-hydroxyeicosatetraenoic acid (20-HETE) from arachidonic acid. Selective vs CYP4A11 (IC50 >150 μM). The dual effect: (a) increases tissue vitamin E, (b) reduces 20-HETE, a vasoconstrictor implicated in hypertension. This is the central biochemical mechanism.
ACE inhibition and eNOS upregulation
Sesame lignans (sesamin, sesamolin) inhibit angiotensin-converting enzyme (ACE) and enhance endothelial nitric oxide synthase (eNOS) activity, promoting vasodilation and blood pressure regulation. Animal studies (Nakano, Iwasa) show sesamin metabolites induce endothelial NO-dependent vasorelaxation independent of antioxidant effect.
NADPH oxidase downregulation in vasculature
Sesamin downregulates NADPH oxidase subunits (p22-phox, p47-phox, gp91-phox) in vascular smooth muscle and endothelium of hypertensive animals, reducing vascular ROS production and improving endothelial function. Acts in concert with eNOS upregulation to restore vascular health.
Hepatic fatty acid oxidation enhancement
Sesamin is a potent inducer of hepatic fatty acid oxidation enzymes — particularly carnitine palmitoyltransferase, β-oxidation enzymes, and PPAR-α target genes. Mechanistic basis for hepatoprotective effects in fatty liver models and may contribute to lipid profile improvements observed clinically.
Clinical trials
Double-blind, crossover, placebo-controlled trial (Miyawaki T, Aono H, Toyoda-Ono Y, Maeda H, Kiso Y, J Nutr Sci Vitaminol (Tokyo) 55(1):87-91, doi:10.3177/jnsv.55.87).
25 middle-aged subjects with mild hypertension. Divided into two groups matched by age and BMI. Crossover design with 60 mg/day sesamin or placebo for 4 weeks each.
Sesamin 60 mg/day for 4 weeks significantly reduced systolic and diastolic blood pressure in mildly hypertensive humans. The trial reported a reduction of a few mmHg. Used 60 mg/day; this small (n=25) crossover is the main human trial at this dose and has not been widely replicated. Cited in subsequent pooled analyses of sesame research; no clinical guideline recommends sesamin for blood pressure.
Randomized controlled crossover trial (Wu JH, Hodgson JM, Puddey IB, Belski R, Burke V, Croft KD 2009, Hypertension 54(5):1151-1158, doi:10.1161/HYPERTENSIONAHA.109.139352).
33 overweight men and women in randomized controlled crossover. 25 g/d sesame (~50 mg/d sesame lignan) or isocaloric matched control for 5 weeks each.
Sesame supplementation reduced plasma 20-HETE by 28% (P<0.001) and urinary 20-HETE by 32% (P<0.001). In vitro: sesamin inhibited human renal and liver microsome 20-HETE synthesis (IC50 1.9 μM CYP4F2 vs >150 μM CYP4A11 — highly selective). Urinary sodium, potassium, and BP unchanged in this short overweight cohort. First human evidence that sesame inhibits CYP4F2-mediated 20-HETE synthesis, supporting a plausible mechanistic basis for the blood pressure effects seen in other sesame trials.
Pilot clinical trial (Wichitsranoi J, Weerapreeyakul N, Boonsiri P, Settasatian C, Settasatian N, Komanasin N, Sirijaichingkul S, Khampitak T, Tangrassameeprasert R, Nutr J 10:82, doi:10.1186/1475-2891-10-82).
Pre-hypertensive humans randomized to 2.5 g/day black sesame meal capsules vs placebo for 4 weeks.
Black sesame meal significantly reduced systolic blood pressure and increased plasma vitamin E (γ-tocopherol). Reduced malondialdehyde (lipid peroxidation marker) and increased reduced glutathione, indicating improved oxidative stress balance. Provides additional support for sesame lignan effects on BP and antioxidant status in pre-hypertensive populations.