Acute Effect of Herbs and Spices Intake on Endothelial Function and Metabolic Markers in Overweight or Obese Adults

Abstract

Objectives: Herbs and Spices (H/S) contain an array of bioactive compounds with purported health benefits. This study investigated the effect of acute H/S intake on vascular and metabolic health indicators, including flow-mediated vasodilation (FMD), glucose control and inflammatory markers over 24 h in overweight or obese individuals. Methods: In this randomized, single-blinded, 4-arm, 24-h, crossover clinical trial, subjects (n = 25, age 37 ± 15 years, BMI 28.5 ± 2.8 kg/m 2 , mean ± SD) consumed a high-fat and high-carbohydrate (HFHC) challenge meal (about 810 kcal) without (control) or with three different combinations of commercially-available H/S: Italian herbs (rosemary, basil, thyme, oregano, and parsley), cinnamon, or pumpkin pie spice (cinnamon, ginger, nutmeg, and allspice) on four separate days at least three days apart. Meals provided 35% of subjects energy to maintain weight and 1 g H/S per 135 kcal. FMD and blood samples were collected at 0, 2, 4, 5.5, 7, and 24 h for endpoint analysis (additional blood samples at 0.5 and 1 h for insulin/glucose). Mixed-model analysis of repeated measures via PROC MIXED PC-SAS 9.4 was performed on primary and secondary outcome variables. FMD was the primary outcome. Results: The addition of H/S in HFHC meals significantly reduced postprandial insulin concentrations over 7 h compared to control (P = 0.03) with no significant decrease in glucose (P = 0.17) compared to the control meal. A significant interaction between H/S and age (P = 0.003) suggested benefits of H/S on insulinemia in individuals 41-65 years. Preliminary analysis showed significant effects of test meal (P < 0.05) on plasma interleukin-6 (IL-6). FMD assessment revealed increased %FMD 24 h after H/S consumption compared to the control meal (P = 0.04), suggesting a possible effect of gut microbial-derived H/S bioactive metabolites, which is under study. Conclusions: This study demonstrated the vascular and metabolic effects of meals differing in herbs and spices. Herbs and spices may improve vascular function after 24 h consumption and have different potencies on metabolic indices in different age groups in overweight or obese individuals.