IMPACT OF A HIGH-POLYPHENOL ROOIBOS TEA INTERVENTION ON POSTPRANDIAL LIPEMIA AND ENDOTHELIAL FUNCTION IN ADULTS WITH METABOLIC SYNDROME

Tahira  Jamil; Vaneeza Iftikhar

Authors

Tahira Jamil Abasyn University, Peshawar, Pakistan. Author
Vaneeza Iftikhar The University of Faisalabad, Pakistan. Author

Keywords:

Endothelial Function, Flavonoids, Metabolic Syndrome, Polyphenols, Postprandial Lipemia, Rooibos, Triglycerides

Abstract

Background: Metabolic syndrome is associated with impaired postprandial lipid metabolism and endothelial dysfunction, both of which contribute to increased cardiovascular risk. Nutritional strategies rich in bioactive compounds, such as polyphenols, have been suggested to improve these post-meal metabolic disturbances. Rooibos (Aspalathus linearis), a herbal tea high in unique polyphenols, has demonstrated potential antioxidant and vascular benefits, yet controlled human trials evaluating its postprandial effects remain limited.

Objective: This RC trial was designed to investigate whether the daily intake of rooibos tea, a beverage rich in polyphenols, could beneficially alter post-meal lipid levels and vascular function in individuals diagnosed with metabolic syndrome.

Methods: The study involved 60 adult participants with metabolic syndrome, randomly allocated into two groups of 30. One group consumed high-polyphenol rooibos tea daily, while the other received a control drink. Following the consumption of a standardized high-fat meal on assessment days, blood was drawn from fasting participants and again at several time points afterward to measure triglyceride levels. Vascular endothelial function was assessed via flow-mediated dilation of the brachial artery. Statistical evaluation of the data included paired and independent t-tests, along with repeated-measures analysis of variance (ANOVA) to compare outcomes between the two groups.

Conclusion: Daily high-polyphenol rooibos tea consumption effectively improves postprandial lipid metabolism and endothelial function in adults with metabolic syndrome. These findings support its potential as a practical dietary strategy to reduce cardiometabolic risk and promote vascular health.

Author Biographies

Tahira Jamil, Abasyn University, Peshawar, Pakistan.

Lecturer, Pharmacy Department, Abasyn University, Peshawar, Pakistan.
Vaneeza Iftikhar, The University of Faisalabad, Pakistan.

Student of Bacholar in Dietatics and Nutrition, The University of Faisalabad, Pakistan.

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