Sex-Specific Effects of Chronic Dietary Capsaicin on Blood Pressure and Arterial Stiffness

Introduction: Cardiovascular disease (CVD) is the leading cause of death in the United States. CVD disproportionately impacts men and women, with premenopausal women at lower risk. In order to protect against CVD, it is crucial to identify interventions to reduce CVD risk and mortality. It has been shown that consuming capsaicin, the active component of chili peppers, improves cardiovascular health in animal models. Regular consumption of spicy peppers has been suggested to lower CVD mortality, yet the impact of dietary capsaicin on cardiovascular health hasn't been directly examined in humans. Objective: We assessed the possible sex specific impact of six weeks of dietary capsaicin on central and peripheral blood pressure and arterial stiffness in a double-blind randomized placebo-controlled trial. We hypothesized that dietary capsaicin would improve blood pressure and arterial stiffness measures, with a greater effect in males. Methods: Seventy-one men (n=36) and women (n=35) were assessed at baseline and after 6-weeks of dietary capsaicin or placebo. Using the oscillometric cuff technique, peripheral pressures were acquired and central pressures obtained using a generalized transfer function with subsequent pulse wave analysis (Sphygmocor Xcel, Atcor Medical). A femoral cuff and carotid tonometer were used to assess pulse wave velocity and pulse transit time. Results: Several sex differences were observed, including central and peripheral systolic blood pressures, pulse pressure, heart rate, subendocardial viability ratio, and forward pulse height (sex, all p< 0.025, η 2 p >0.078), with females exhibiting more favorable values. There was a significant interaction of sex and condition on central diastolic blood pressure (sex*condition, p=0.030, η 2 p=0.072), where females had lower cDBP with capsaicin as compared to placebo, whereas males had higher cDBP with capsaicin as compared to placebo. No other significant interaction effects were noted (all, p >0.05). Conclusion: Central diastolic blood pressure was differentially impacted by dietary capsaicin in men and women, and thus sex needs to be considered in future studies exploring the cardiovascular effects of dietary capsaicin, and further research is needed. Funding: This work was funded by the AHA, awarded to SJI (#24AIREA1247045). This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.