# Roselle (Hibiscus sabdariffa) *Hibiscus, ‘the Roselle of India or Red Sorrel of the W. Indies’; in Bombay bazaars ‘Rozal’; *Hibiscus sabdariffa* L.* **Known today as.** *Hibiscus sabdariffa*, of the mallow family, Malvaceae, an erect annual shrub with a purple stem and yellow flowers, cultivated, Kirtikar and Basu write, in the hotter parts of India. After flowering its calyx swells into a purplish fleshy cup, the part chiefly eaten. A note of 1913 that they reprint found its acidity due entirely to malic acid, its composition “very similar to that of the cranberry.” Kind: Plant > **Caution.** The 2025 umbrella review found a minor, clinically insignificant rise in one liver enzyme, aspartate aminotransferase, without more adverse events, and concluded that although it is generally considered safe, “long-term and therapeutic dosing safety requires careful monitoring.” ## What was it used for? A food, a jelly, and a diet drink. Kirtikar and Basu record that the succulent calyx was made into “Roselle” jelly in Bombay and, dried, used much like tamarind in curries; that in bilious conditions a diet drink was made by boiling it with water and a little salt, pepper, asafoetida, and molasses; and that a decoction of the seeds was recommended for painful urination, dyspepsia, and debility. They add that the fruit “possesses anti-scorbutic properties,” and that the leaves were regarded as emollient and cooked as a vegetable. ## What does modern science say? No European monograph covers it, and the modern trials, of its extract or tea, have looked chiefly at blood pressure. A 2022 meta-analysis of thirteen trials found that it lowered blood pressure against placebo in mild-to-moderate hypertension, but not in people whose hypertension came with the metabolic syndrome, and that it was no better than antihypertensive drugs. Another of seventeen trials (2022) found blood pressure falls similar to those from medication, greatest in those with raised pressure at the start, and lower LDL cholesterol. An umbrella review of twenty-six trials (2025) found a dose-dependent fall in blood pressure, comparable to that from antihypertensive drugs, with lower total and LDL cholesterol and fasting blood sugar and higher HDL cholesterol. For weight, a 2024 meta-analysis of six trials found no clinical benefit. ## Pharmacognosy and toxicology - **malic acid**: the whole of the calyx’s acidity, in the 1913 note Kirtikar and Basu reprint **Mechanism.** Not established in the sources read for this entry. **Standing.** There is no European monograph. Meta-analyses (2022, 2025) find that its extract or tea lowers blood pressure. ## What did the older authorities say? **Kirtikar and Basu, *Indian Medicinal Plants* (1918).** The note they reprint from 1913 records that roselle had lately been introduced into the Philippine Islands, “the sole representative of a type, in which the calyx supplies the chief edible portion of the plant,” harvested when it has swollen to look like a large bud and made into jam or jelly of a brilliant red colour and pleasant acid taste, and into syrup and wine. ## Sources - Kirtikar, K. R., & Basu, B. D. (1918). *Indian Medicinal Plants*, vol. 1, “Hibiscus sabdariffa (no. 165).” Internet Archive, b31359644_0001. - Abdelmonem M, et al. (2022). Efficacy of Hibiscus sabdariffa on Reducing Blood Pressure in Patients With Mild-to-Moderate Hypertension: A Systematic Review and Meta-Analysis of Published Randomized Controlled Trials. *Journal of cardiovascular pharmacology*. PMID 34694241. - Ellis LR, et al. (2022). A systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers. *Nutrition reviews*. PMID 34927694. - Norouzzadeh M, et al. (2025). Efficacy and safety of Hibiscus sabdariffa in cardiometabolic health: An overview of reviews and updated dose-response meta-analysis. *Complementary therapies in medicine*. PMID 39870328. - Dilokthornsakul P, et al. (2024). Clinical effects of Hibiscus sabdariffa Linn. on obesity treatment: A systematic review and meta-analysis of randomized controlled trials. *Complementary therapies in medicine*. PMID 38878905. - Kirtikar, K. R., & Basu, B. D. (1918). *Indian Medicinal Plants*, vol. 1, “Hibiscus sabdariffa (no. 165).” Internet Archive, b31359644_0001. - Abdelmonem M, et al. (2022). Efficacy of Hibiscus sabdariffa on Reducing Blood Pressure in Patients With Mild-to-Moderate Hypertension: A Systematic Review and Meta-Analysis of Published Randomized Controlled Trials. *Journal of cardiovascular pharmacology*. PMID 34694241. - Norouzzadeh M, et al. (2025). Efficacy and safety of Hibiscus sabdariffa in cardiometabolic health: An overview of reviews and updated dose-response meta-analysis. *Complementary therapies in medicine*. PMID 39870328. --- *Roselle.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-17. The Thinking Press. https://thethinkingpress.org/materia-medica/roselle Historical description, not medical advice.