Cardiometabolic Disorders and Dietary Guidelines

Cardiometabolic disorders are a global burden on health systems, and their management is of utmost importance. Dietary guidelines in many countries, including the United States, United Kingdom, and Australia, recommend flavoring foods with herbs and spices as a strategy to reduce salt intake.

A randomized trial by Kristina S Petersen and team has revealed that adding herbs and spices to meals may help lower blood pressure. In a US-style diet, the addition of a relatively high culinary dosage of mixed herbs and spices of 6.6 g tended to improve 24-hour blood pressure after 4 weeks, compared with lower dosages of 0.5 and 3.3 g, in adults at elevated risk of cardiometabolic diseases.

The findings of the study are published in The American Journal of Clinical Nutrition.

Study Objective

The objective of the study was to assess the effect of an average American diet containing herbs and spices at 0.5 (low-spice diet; LSD), 3.3 (moderate-spice diet; MSD), and 6.6 (high-spice diet; HSD) g • day^-1 • 2100 kcal⁻¹ on lipids and lipoproteins as well as other risk factors for cardiometabolic diseases in at-risk adults.

Study Design

The study was a 3-period, randomized, crossover, controlled-feeding study with 71 participants conducted at the Pennsylvania State University. Each diet was consumed for 4 weeks with a minimum 2-week washout period. Outcomes were assessed at baseline and the end of each diet period.

Study Results

• No difference between-diet effects were observed for LDL cholesterol, the primary outcome.
• Between-diet differences were observed for mean 24-hour systolic (P = 0.02) and diastolic (P = 0.005) ambulatory blood pressure.
• The HSD lowered mean 24-hour systolic blood pressure compared with the MSD (−1.9 mm Hg; 95% CI: −3.6, −0.2 mm Hg; P = 0.02); the difference between the HSD and LSD was not statistically significant (−1.6 mm Hg; 95% CI: −3.3, 0.04 mm Hg; P = 0.058).
• The HSD lowered mean 24-hour diastolic blood pressure compared with the LSD (−1.5 mm Hg; 95% CI: −2.5, −0.4 mm Hg; P = 0.003).
• No differences were detected between the LSD and MSD. No between-diet effects were observed for clinic-measured blood pressure, markers of glycemia, or vascular function.

Petersen and team concluded that "In the context of a suboptimal US-style diet, the addition of a relatively high culinary dosage of mixed herbs and spices (6.6 g • d⁻¹ • 2100 kcal⁻¹) tended to improve 24-hour blood pressure after 4 weeks, compared with lower dosages (0.5 and 3.3 g • d⁻¹ • 2100 kcal⁻¹), in adults at elevated risk of cardiometabolic diseases."

Reference

Kristina S Petersen, Kristin M Davis, Connie J Rogers, David N Proctor, Sheila G West, Penny M Kris-Etherton, Herbs and spices at a relatively high culinary dosage improves 24-hour ambulatory blood pressure in adults at risk of cardiometabolic diseases: a randomized, crossover, controlled-feeding study, The American Journal of Clinical Nutrition, 2021;, nqab291, https://doi.org/10.1093/ajcn/nqab291