Breastfeeding parents often consider the safety of various substances and their potential impact on breast milk supply. This consideration extends to common ingredients found in everyday products. This article explores the current understanding of menthol’s relationship with breast milk supply.
Understanding Menthol’s Effect on Milk Supply
Research directly investigating menthol’s effect on human lactation is limited, relying more on anecdotal accounts and studies involving its primary source, peppermint. Historically, peppermint has been associated with a potential decrease in milk supply, and some cultures have even used it to suppress lactation. While no extensive human clinical trials have definitively demonstrated lactation suppression from peppermint or menthol intake, laboratory studies on mammary epithelial cells and animal models suggest a possible link.
A 2020 study found that peppermint oil, and specifically menthol, could suppress milk production in lactating mammary epithelial cells and mice. This research indicated a reduction in beta-casein, a major milk protein, and changes in milk fat droplet size. The impact depends on the concentration and frequency of exposure. Occasional, low-dose exposure is less likely to cause issues than regular, higher-dose use of concentrated forms like peppermint essential oil or strong teas. After oral ingestion, menthol is rapidly converted into a different compound in humans, and whether this converted form has the same suppressive effect on lactation is not yet clear.
How Menthol May Influence Lactation
Menthol may influence milk production through several proposed mechanisms. One pathway involves its potential to activate certain cold-sensitive receptors, known as TRPM8 and TRPA1, found in mammary epithelial cells. Activation of these receptors could theoretically reduce blood flow to the mammary glands, which might impede milk synthesis.
Beyond its effect on receptors, menthol has been observed to interfere with specific cellular signaling pathways. Studies show that menthol can inactivate STAT5 and mTOR pathways. These pathways are involved in prolactin production, a hormone crucial for milk production. By affecting these processes, menthol might directly inhibit the cellular machinery responsible for generating breast milk components.
Everyday Menthol Sources
Menthol is a common compound found in a variety of products encountered daily by breastfeeding parents. Oral products frequently contain menthol for its cooling sensation and flavor. These include mints, chewing gum, cough drops, lozenges, and certain toothpastes and mouthwashes.
Topical applications also incorporate menthol for its analgesic and cooling properties. Examples include muscle rubs, pain relief creams, balms such as VapoRub, and some lip balms. Additionally, menthol can be found in inhaled products like certain nasal inhalers and, notably, in some vaping products. The concentration of menthol varies considerably across these different product types, which can influence its potential impact.
Recommendations for Breastfeeding Parents
For breastfeeding parents concerned about menthol’s effect on milk supply, moderation in product use is advised. It is wise to limit products with high concentrations of menthol or peppermint oil, particularly if there are existing concerns about milk production. Occasional consumption of mildly flavored items like a single mint or a cup of weak peppermint tea is less likely to cause an issue for most individuals.
Monitoring milk supply closely is important if menthol-containing products are used regularly. Changes in infant feeding patterns or a perceived decrease in milk volume could suggest an impact. Maintaining good hydration, ensuring frequent and effective nursing or pumping sessions, and consuming a balanced diet are important practices for supporting a healthy milk supply. Consulting with a healthcare provider or a lactation consultant is always recommended for personalized guidance regarding milk supply concerns or the use of specific products during breastfeeding.