Daily Chewing of Whole Cloves: Safety and Recommendations
Daily chewing of whole cloves is not recommended for healthy adults due to significant cytotoxicity risks to oral tissues, even at low concentrations, with no established safe dosage for this practice.
Evidence of Harm
The available research demonstrates clear safety concerns with direct oral exposure to clove:
- Clove oil exhibits severe cytotoxicity to human cells at concentrations as low as 0.03% (v/v), with up to 73% of this toxic effect attributable to eugenol, the primary active component comprising 50-78% of clove oil 1
- Human fibroblasts and endothelial cells—the types of cells lining the mouth and gums—show significant cell death when exposed to clove oil and eugenol 1
- The cytotoxic effects occur at concentrations far lower than what would be released during prolonged chewing of whole cloves 1
Lack of Safety Data for Oral Consumption
While clove has documented uses, none support daily chewing:
- Clove essential oil is recognized for food preservation, flavoring, and topical medicinal applications, but these uses involve diluted forms or external application—not direct, prolonged oral mucosal contact 2, 3
- Traditional medicinal use involves clove oil as a topical application for pain relief, not as a substance for daily chewing 1
- No clinical guidelines or research studies establish safe dosing parameters for daily chewing of whole cloves in healthy adults 3, 4
Specific Risks
Beyond cytotoxicity, additional concerns exist:
- Reproductive system effects have been reported with clove and eugenol, though mechanisms remain poorly understood and effects vary by dose, duration, and extract type 5
- The concentration of bioactive compounds (eugenol, β-caryophyllene, α-humulene) varies significantly between clove sources, making consistent dosing impossible 3
- Prolonged mucosal exposure to eugenol may cause tissue damage beyond what standard toxicity testing reveals 1
Clinical Recommendation
Avoid daily chewing of whole cloves entirely. If seeking the antimicrobial or antioxidant benefits of clove:
- Use clove in culinary amounts as a spice in cooked foods, where concentrations are diluted 2, 4
- For dental pain, apply pharmaceutical-grade clove oil topically and briefly, not through prolonged chewing 1
- Consider that clove's antimicrobial properties are best utilized in food preservation applications, not through direct consumption 2
Critical Caveat
The designation of clove oil and eugenol as "generally recognized as safe" by regulatory bodies applies to their use as food additives and flavorings in diluted forms—not to concentrated exposure through daily chewing of whole cloves 1. This distinction is crucial, as the safety designation does not extend to practices that create prolonged, high-concentration mucosal contact.