What is it?
The compound that gives mint its cooling feel and part of its scent. Natural menthol is isolated from cornmint (Mentha canadensis), and menthol with the same structure is also made synthetically. It is used in toothpaste and other oral-care products, in cosmetics and over-the-counter medicinal products for its cooling effect, and as a flavor in foods such as chewing gum.
Key information
- The EU's Scientific Committee on Consumer Safety classifies menthol as an established contact allergen, though positive patch tests are uncommon.
- New products placed on the EU market since August 2026 must list menthol above 0.001 percent in leave-on or 0.01 percent in rinse-off products.
- The FAO/WHO expert committee on food additives (JECFA) set an acceptable daily intake of 0 to 4 mg per kilogram of body weight and found no safety concern for its use as a flavoring.
- Menthol is one of the most effective plant terpenes for helping medicines penetrate the skin.
More information
Menthol is a cyclic monoterpene alcohol. The preferred form is (-)-menthol, also called L-menthol, whether isolated from plants or synthesized with the same structure; trade products also include DL-menthol. It occurs in several essential oils, including peppermint oil. Beyond its flavor and cooling effect, a 2013 scientific review noted that menthol is one of the most effective terpenes used to increase the skin penetration of drugs.
In its 2012 opinion on fragrance allergens, the EU’s Scientific Committee on Consumer Safety (SCCS) classified menthol as an established contact allergen, but reactions are uncommon. In one study, 1 of 1,147 patients tested had a weak positive reaction. Among 512 patients referred by a dental department for mouth symptoms, 10 reacted to menthol, and most improved markedly after they stopped using peppermint-containing oral products. Menthol has also been reported to cause contact urticaria (hives), and in single cases rhinitis and asthma. Following that opinion, the EU now requires menthol to be named on labels of products placed on the market from August 2026.
As a food flavoring, menthol was evaluated by JECFA, the joint expert committee of the United Nations Food and Agriculture Organization and the World Health Organization. It set an acceptable daily intake of 0 to 4 mg per kilogram of body weight and found no safety concern at current levels of intake. If mint-flavored products seem to irritate your mouth or lips, look for menthol, peppermint and spearmint on labels. See also our Peppermint Oil profile.
Sources: SCCS: Opinion on fragrance allergens in cosmetic products (2012); Official Journal of the EU: Commission Regulation (EU) 2023/1545 on labelling of fragrance allergens; WHO/JECFA (INCHEM): Evaluation of menthol; Phytochemistry (2013): Menthol, a simple monoterpene with remarkable biological properties
