Plant Profile

Hibiscus

Compiled by the Omnia Sana editorial team from the plant database ·Last updated August 15, 2026

Hibiscus sabdariffa

Family: Malvaceae · Parts used: Calyx (dried flower calyces) · Also known as: Roselle, Sorrel, Karkade

The complete database record: 3 documented constituents, 4 pharmacological actions, 5 traditional / indicated uses, with 18 cited sources.

Botanical Description

Erect, branching annual to short-lived perennial shrub with reddish stems and deeply lobed, palmate leaves. Pale yellow to pink hibiscus-type flowers with a dark centre open briefly, followed by the fleshy, bright red calyx (sepals) that swells around the seed capsule - this calyx, not the flower petals, is the part harvested and used.

Height: 1-2.5 m

Habit: Erect, branching annual to short-lived perennial shrub

Leaves: Deeply lobed, palmate

Flowers: Pale yellow to pink, hibiscus-type, with a dark centre, short-lived

Stem: Reddish, branching

Root: Taproot with fibrous lateral roots

Fruit: Fleshy, bright red calyx surrounding a seed capsule (the calyx is the medicinal/culinary part)

Flowering Period: Summer to autumn

Habitat & Distribution

Believed native to West Africa; widely cultivated throughout the tropics and subtropics (Africa, Asia, the Caribbean and Central America) for its edible calyces.

Harvesting

The fleshy red calyces are hand-picked shortly after the flower petals fall, while still fresh and plump, then separated from the seed pod and dried for storage.

Parts: Calyx (dried flower calyces)

Key Constituents

Anthocyanins (delphinidin and cyanidin glucosides)^[4]

The red pigments and principal antioxidant/vasoactive constituents.

Anthocyanins

Organic acids (including hibiscus/hydroxycitric acid) and polyphenols^[4]

Contribute to the tartness and cardiometabolic effects.

Phenolic compounds

Flavonoids^[4]

Additional antioxidant constituents.

Flavonoids

Pharmacological Actions

Antidiabetic (blood-sugar lowering)^{[5, 11, 13]}

Lowers fasting blood glucose

Antihypertensive^{[3, 4, 7, 8, 9, 10, 13, 14]}

Lowers blood pressure, with the greatest effect in people with raised blood pressure

Antioxidant^{[1, 2, 4]}

Lipid-lowering^{[4, 6, 8, 11, 14]}

Improves the lipid profile - lowers LDL and total cholesterol

Traditional & Indicated Uses

Blood sugar / diabetes support^[13]Good · 7/10

inferred from antidiabetic action

Evidence: 7

Label: Blood sugar / diabetes support

more plants for blood sugar / diabetes support →detailed sources →

Cardiovascular / heart health^{[3, 4, 13, 14]}Strong · 9/10

inferred from antihypertensive action

Evidence: 9

Label: Cardiovascular / heart health

more plants for cardiovascular / heart health →detailed sources →

High blood pressure^{[3, 4, 13, 14]}Strong · 9/10

Lowers blood pressure, with the greatest effect in people with raised blood pressure

Evidence: 9

Label: High blood pressure

more plants for high blood pressure →detailed sources →

High cholesterol^{[4, 14]}Good · 8/10

inferred from lipid-lowering action

Evidence: 8

Label: High cholesterol

more plants for high cholesterol →detailed sources →

Metabolic support^[13]Good · 7/10

inferred from antidiabetic action

Evidence: 7

Label: Metabolic support

more plants for metabolic support →detailed sources →

Traditional Use & History

Hibiscus calyx (known as roselle, sorrel or karkade in different regions) has a long traditional use across Africa, the Middle East and the Caribbean as a tart, cooling beverage and folk remedy for fevers and mild hypertension; this traditional blood-pressure-lowering reputation is now well supported by clinical trials of hibiscus tea/extract.^[4]

Preparations

Infusion ('hibiscus tea')^[4]

Dried calyces steeped in hot or cold water as a tart, ruby-red infusion; the form used in most clinical blood-pressure studies.

Standardised extract^[4]

Concentrated calyx extract, taken as capsules for cardiometabolic support.

Dosage

Infusion^[4]

Clinical trials for blood pressure commonly use around 1.5-3 g of dried calyx (roughly one to two cups of tea) daily. Educational reference only, not a prescription.

Safety, Cautions & Contraindications

Safety note^{[3, 4]}Info

Its blood-pressure-lowering effect can add to that of antihypertensive medicines; monitor blood pressure if you take them. Note that it is not superior to standard antihypertensive drugs and did not significantly lower blood pressure in the metabolic-syndrome subgroup.

Safety note^[4]Caution

May alter the absorption or levels of some medicines (e.g. paracetamol, chloroquine); avoid concentrated or medicinal doses in pregnancy.

Herb-Drug Interactions

Antihypertensives^{[15, 16]}Caution

Mechanism: Hibiscus (roselle) lowers systolic and diastolic blood pressure in trials (a meta-analysis found reductions of about 7.6/3.5 mmHg); combined with blood-pressure medicines it may add to their effect and cause blood pressure to drop too low, so monitor blood pressure.

Reviewed By: Omnia Sana (owner-authorized)

Reviewed Date: 2026-07-03

Herb-Herb Pairings

Olive^{[16, 17]}

Hibiscus and olive leaf can each mildly lower blood pressure, so taking them together - especially alongside blood-pressure medicines - may add up and lower blood pressure more than expected. Monitor your blood pressure.

Type: caution

Reviewed By: Omnia Sana (owner-authorized)

Reviewed Date: 2026-07-03

Black Cumin^{[16, 18]}

Hibiscus and black seed (Nigella sativa) can each mildly lower blood pressure, so taking them together - especially alongside blood-pressure medicines - may add up and lower blood pressure more than expected. Monitor your blood pressure.

Type: caution

Reviewed By: Omnia Sana (owner-authorized)

Reviewed Date: 2026-07-03

Harvest Readiness

^[12]

Part: flower

Signals: Harvest the calyces once they have enlarged, turned fleshy and deep crimson red (as the seed capsule matures inside), before they dry and become woody.

Basis: traditional

Source Quote: becoming fleshy and a deep crimson red as the fruit matures

Species Confirmed: 1

Notes: Wikipedia Roselle (REF-3271) for Hibiscus sabdariffa; the harvested organ is the persistent calyx, ready when it has enlarged and become fleshy and deep crimson as the fruit (seed capsule) matures inside - picked before it dries and turns woody. Mapped to the canonical 'flower' organ (the fleshy calyx is the floral structure gathered). Single source -> provisional.

External Identifiers

GBIF ›Wikidata ›

References & Sources

Da-Costa-Rocha, I., Bonnlaender, B., Sievers, H., Pischel, I. and Heinrich, M (2014) 'Hibiscus sabdariffa L. - a phytochemical and pharmacological review', Food Chemistry, 165, pp. 424-443. doi:10.1016/j.foodchem.2014.05.002 Meta-analysis / review
https://doi.org/10.1016/j.foodchem.2014.05.002
Riaz, G. and Chopra, R (2018) 'A review on phytochemistry and therapeutic uses of Hibiscus sabdariffa L', Biomedicine & Pharmacotherapy, 102, pp. 575-586. doi:10.1016/j.biopha.2018.03.023 Meta-analysis / review
https://doi.org/10.1016/j.biopha.2018.03.023
Abdelmonem, M., Ebada, M.A., Diab, S., Ahmed, M.M., Zaazouee, M.S. and others (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, 79(1), pp. e64--e74. doi:10.1097/FJC.0000000000001161 Meta-analysis / review
https://doi.org/10.1097/FJC.0000000000001161
Ellis, L.R., Zulfiqar, S., Holmes, M., Marshall, L., Dye, L. and Boesch, C (2022) 'A systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers', Nutrition Reviews. doi:10.1093/nutrit/nuab104 Meta-analysis / review
https://doi.org/10.1093/nutrit/nuab104
Jamrozik, D., Borymska, W. and Kaczmarczyk-Zebrowska, I (2022) 'Hibiscus sabdariffa in Diabetes Prevention and Treatment - Does It Work? An Evidence-Based Review', Foods, 11(14), pp. 2134. doi:10.3390/foods11142134 Meta-analysis / review
https://doi.org/10.3390/foods11142134
Aziz, Z., Wong, S.Y. and Chong, N.J (2013) 'Effects of Hibiscus sabdariffa L. on serum lipids: a systematic review and meta-analysis', Journal of Ethnopharmacology, 150(2), pp. 442-450. doi:10.1016/j.jep.2013.09.042 Meta-analysis / review
https://doi.org/10.1016/j.jep.2013.09.042
Wahabi, H.A., Alansary, L.A., Al-Sabban, A.H. and Glasziou, P (2009) 'The effectiveness of Hibiscus sabdariffa in the treatment of hypertension: a systematic review', Phytomedicine, 17(2), pp. 83-86. doi:10.1016/j.phymed.2009.09.002 Meta-analysis / review
https://doi.org/10.1016/j.phymed.2009.09.002
Hopkins, A.L., Lamm, M.G., Funk, J.L. and Ritenbaugh, C (2013) 'Hibiscus sabdariffa L. in the treatment of hypertension and hyperlipidemia: a comprehensive review of animal and human studies', Fitoterapia, 85, pp. 84-94. doi:10.1016/j.fitote.2013.01.003 Meta-analysis / review
https://doi.org/10.1016/j.fitote.2013.01.003
Joven, J., March, I., Espinel, E., Fernandez-Arroyo, S., Rodriguez-Gallego, E., Aragones, G., Beltran-Debon, R., Alonso-Villaverde, C., Rios, L., Martin-Paredero, V., Menendez, J.A., Micol, V., Segura-Carretero, A. and Camps, J (2014) 'Hibiscus sabdariffa extract lowers blood pressure and improves endothelial function', Molecular Nutrition & Food Research, 58(6), pp. 1374-1378. doi:10.1002/mnfr.201300774 Clinical study
https://doi.org/10.1002/mnfr.201300774
Bourqui, A., Niang, E.A.B., Graz, B., Diop, E.A., Dahaba, M., Thiaw, I., Soumare, K., Valmaggia, P., Nogueira, R.C., Cavin, A., Al-Anbaki, M. and Seck, S.M (2020) 'Hypertension treatment with Combretum micranthum or Hibiscus sabdariffa, as decoction or tablet: a randomized clinical trial', Journal of Human Hypertension, 35(9), pp. 800-808. doi:10.1038/s41371-020-00415-1 Randomized trial
https://doi.org/10.1038/s41371-020-00415-1
Perez-Torres, I., Ruiz-Ramirez, A., Banos, G. and El-Hafidi, M (2013) 'Hibiscus sabdariffa Linnaeus (Malvaceae), curcumin and resveratrol as alternative medicinal agents against metabolic syndrome', Cardiovascular & Hematological Agents in Medicinal Chemistry, 11(1), pp. 25-37. doi:10.2174/1871525711311010006 Meta-analysis / review
https://doi.org/10.2174/1871525711311010006
Wikipedia contributors 'Roselle (plant)'. Available at: https://en.wikipedia.org/wiki/Roselle_(plant) Traditional / reference
https://en.wikipedia.org/wiki/Roselle_(plant)
Najafpour Boushehri, S., Karimbeiki, R., Ghasempour, S., Ghalishourani, S.S., Pourmasoumi, M. and others (2020) 'The efficacy of sour tea (Hibiscus sabdariffa L.) on selected cardiovascular disease risk factors: A systematic review and meta-analysis of randomized clinical trials', Phytotherapy Research, 34(2), pp. 329--339. doi:10.1002/ptr.6541 Meta-analysis / review
https://doi.org/10.1002/ptr.6541
Garcia-Munoz, A.M., Garcia-Guillen, A.I., Victoria-Montesinos, D., Abellan-Ruiz, M.S., Alburquerque-Gonzalez, B. and Canovas, F (2023) 'Effect of the Combination of Hibiscus sabdariffa with Other Plant Extracts in the Prevention of Metabolic Syndrome: A Systematic Review and Meta-Analysis', Foods. doi:10.3390/foods12112269 Meta-analysis / review
https://doi.org/10.3390/foods12112269
Abdelmonem, M., Ebada, M.A., Diab, S., Ahmed, M.M., Zaazouee, M.S., Essa, T.M., ElBaz, Z.S., Ghaith, H.S., Abdella, W.S., Ebada, M. and Negida, A (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, 79(1), pp. e64-e74. doi:10.1097/FJC.0000000000001161 Meta-analysis / review
https://doi.org/10.1097/FJC.0000000000001161
Serban, C., Sahebkar, A., Ursoniu, S., Andrica, F. and Banach, M (2015) 'Effect of sour tea (Hibiscus sabdariffa L.) on arterial hypertension: a systematic review and meta-analysis of randomized controlled trials', Journal of Hypertension, 33(6), pp. 1119-1127. doi:10.1097/HJH.0000000000000585 Meta-analysis / review
https://doi.org/10.1097/HJH.0000000000000585
Ismail, M.A., Norhayati, M.N. and Mohamad, N (2021) 'Olive leaf extract effect on cardiometabolic profile among adults with prehypertension and hypertension: a systematic review and meta-analysis', PeerJ, 9, pp. e11173. doi:10.7717/peerj.11173 Meta-analysis / review
https://doi.org/10.7717/peerj.11173
Sahebkar, A., Soranna, D., Liu, X., Thomopoulos, C., Simental-Mendia, L.E., Derosa, G., Maffioli, P. and Parati, G (2016) 'A systematic review and meta-analysis of randomized controlled trials investigating the effects of supplementation with Nigella sativa (black seed) on blood pressure', Journal of Hypertension, 34(11), pp. 2127-2135. doi:10.1097/HJH.0000000000001049 Meta-analysis / review
https://doi.org/10.1097/HJH.0000000000001049

Selected studies & references

ReviewEffect of the Combination of Hibiscus sabdariffa with Other Plant Extracts in the Prevention of Metabolic Syndrome: A Systematic Review and Meta-Analysis source↗ (2023)

ReviewA systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers source↗ (2022)

ReviewEfficacy 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 source↗ (2022)

ReviewHibiscus sabdariffa in Diabetes Prevention and Treatment - Does It Work? An Evidence-Based Review source↗ (2022)

ReviewOlive leaf extract effect on cardiometabolic profile among adults with prehypertension and hypertension: a systematic review and meta-analysis source↗ (2021)

ReviewThe efficacy of sour tea (Hibiscus sabdariffa L.) on selected cardiovascular disease risk factors: A systematic review and meta-analysis of randomized clinical trials source↗ (2020)

ReviewA review on phytochemistry and therapeutic uses of Hibiscus sabdariffa L. source↗ (2018)

All 17 studies in the Knowledge Finder →

Educational use only. This profile summarises traditional and scientific sources for reference. It is not medical advice and not a substitute for a qualified practitioner. Some plants carry safety cautions and drug interactions - always check before use.
This profile is assembled automatically from the Omnia Sana plant database, which we curate by hand. How this site is built.

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