Clove Buds 101: Spice Your Way to Healthier Days with Science-Backed Insights
Updated: Oct 19
Clove refers to the dried, unopened flower buds of Syzygium aromaticum, an evergreen tree in the Myrtaceae family. Native to the Maluku Islands of Indonesia, cloves have been used for centuries in traditional systems across Asia for oral care, digestion, and as a warming spice. Modern research has focused primarily on eugenol, the main compound in clove essential oil, for its antimicrobial, antioxidant, and analgesic properties.
This article summarizes the composition of clove, its traditional uses, and what current evidence supports.
What Is Clove?
Clove buds contain a high concentration of essential oil, typically 15–20% by weight. The primary bioactive compound is eugenol, which usually makes up 70–85% of the essential oil. Other notable components include:
Acetyl eugenol
β-Caryophyllene
Flavonoids and tannins
Whole cloves retain their volatile oils longer than ground clove. Eugenol content can vary by growing region and harvest conditions.
Where Does Clove Come From?
Cloves originated in the Maluku Islands (Spice Islands) of Indonesia. Today, Indonesia remains the largest producer, followed by Madagascar, Sri Lanka, and India. Clove trees thrive in tropical climates with high humidity and volcanic soils. Buds are harvested by hand when they turn from green to pink, then sun-dried.
Key Studied Properties
Research on clove and eugenol has examined several areas:
Antimicrobial activity: Eugenol and clove essential oil have shown activity against various bacteria and fungi in laboratory studies, including some oral pathogens such as Streptococcus mutans.
Antioxidant effects: Clove ranks among the spices with high antioxidant capacity in laboratory assays.
Analgesic properties: Eugenol has a long history of use in dentistry for temporary toothache relief due to its local anesthetic effects.
Anti-inflammatory potential: Laboratory studies suggest eugenol can influence inflammatory pathways, though human clinical evidence remains limited.
Most of the stronger evidence comes from laboratory and preclinical research. High-quality human clinical trials on whole clove or clove extracts for specific health outcomes are still relatively few.
Digestion and Traditional Use
Clove has traditional use in Ayurveda and other systems for digestive discomfort, bloating, and as a carminative. Some laboratory and animal studies have explored eugenol’s effects on gastric mucus and gastrointestinal motility. However, well-controlled human trials specifically on clove for digestion are limited. Culinary amounts are generally considered safe as part of a varied diet.
Oral Health
Clove oil and eugenol have a long history of use in dentistry for temporary relief of toothache. Eugenol is still used in some dental materials. Laboratory studies show that clove essential oil and eugenol can inhibit certain oral bacteria. Clinical evidence for clove gel or oil in reducing plaque or gingival inflammation is limited and of mixed quality. Clove oil is concentrated and should not be swallowed in large amounts.
Antioxidant Capacity
Clove has scored highly in laboratory antioxidant assays such as ORAC. These in vitro results indicate strong free-radical scavenging potential but do not directly translate to health outcomes in humans. Culinary use of clove contributes small amounts of antioxidants as part of an overall diet.
Safety Considerations
Culinary amounts: Generally recognized as safe.
Clove oil / concentrated extracts: Can cause irritation or toxicity if misused. Undiluted clove oil should not be ingested or applied directly to skin or gums without proper dilution and guidance.
People who should use caution: Those with bleeding disorders, taking blood thinners, or with known allergies to eugenol. Pregnant individuals should stick to food amounts.
NCCIH and other sources note that while clove oil has traditional dental use, evidence for most other health claims is limited.
Conclusion
Clove buds are a traditional spice valued for their high eugenol content and aromatic properties. Laboratory research supports antimicrobial, antioxidant, and analgesic effects of eugenol, particularly in oral applications. Human clinical evidence for broader health benefits remains limited. Clove is best enjoyed in culinary amounts as part of a balanced diet, while concentrated clove oil or extracts should be used carefully and under appropriate guidance.
References
Batiha GE, et al. Syzygium aromaticum L. (Myrtaceae): Traditional Uses, Bioactive Chemical Constituents, Pharmacological and Toxicological Activities. Biomolecules. 2020;10(2):202.
Cortés-Rojas DF, et al. Clove (Syzygium aromaticum): A precious spice. Asian Pacific Journal of Tropical Biomedicine. 2014;4(2):90–96.
Marchese A, et al. Antimicrobial activity of eugenol and essential oils containing eugenol: A mechanistic viewpoint. Critical Reviews in Microbiology. 2017;43(6):668–689.
National Center for Complementary and Integrative Health (NCCIH). Clove.
European Medicines Agency. European Union herbal monograph on Syzygium aromaticum (L.) Merr. et L.M. Perry, floris aetheroleum. EMA/HMPC/534946/2010.
Xu J, et al. Antibacterial activity of eugenol and its derivatives against oral pathogens. Applied Microbiology and Biotechnology. 2016 (various studies).
LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. Clove Oil / Eugenol. National Institute of Diabetes and Digestive and Kidney Diseases.
