Breastfeeding parents often worry that common culinary herbs and spices might affect their ability to produce milk. This concern is particularly true for herbs historically associated with medicinal uses. Oregano is one such herb that prompts questions about its safety and effect on milk volume, making it important to understand its classification within the context of lactation.
Substances That Influence Milk Production
Milk production is influenced by a delicate hormonal balance, and various substances can impact this process. Substances believed to help increase milk supply are called galactagogues. These often include herbs like fenugreek seed, fennel, and blessed thistle, which traditionally influence prolactin levels, the primary hormone responsible for milk production.
Conversely, substances that may decrease milk supply are known as anti-galactagogues. Common herbal examples include sage and large amounts of peppermint, sometimes used intentionally during weaning to dry up milk supply. These herbs are thought to contain compounds with a drying effect, though the exact mechanism on the mammary glands is not fully documented in human studies.
What the Research Says About Oregano
Oregano is generally considered safe for consumption in typical culinary amounts and is classified as “generally recognized as safe” (GRAS) by the U.S. Food and Drug Administration. Concern often stems from its relation to other mint family herbs, like peppermint, which is a known anti-galactagogue in concentrated forms. Oregano contains compounds such as carvacrol and thymol, which have potent antimicrobial properties.
Some anecdotal sources suggest that oregano, particularly in large or concentrated doses, may function as an anti-galactagogue. However, there is little robust clinical evidence classifying it as a potent substance that decreases milk supply in humans. It is crucial to differentiate between the small amount of dried oregano used for seasoning and the high concentration found in essential oils or high-dose supplements.
The limited research available is mixed, with some traditional uses suggesting the opposite effect. In Türkiye, oregano has been traditionally used as a galactagogue, suggesting a cultural belief in its ability to support milk production. Furthermore, studies in dairy cows have shown that supplementation with oregano essential oil can be associated with increased milk yield.
Due to the lack of specific human clinical trials, the consensus leans toward caution regarding high-dose exposure. The potential for oregano to affect milk supply is primarily theoretical, based on the presence of volatile oils, not widespread observation from normal dietary consumption. Therefore, a nursing parent is unlikely to experience a decrease in milk volume from using oregano as a seasoning in everyday cooking.
Guidelines for Using Culinary Herbs During Lactation
When incorporating any herb into the diet while nursing, moderation is the most sensible approach. Most herbs used for seasoning, including oregano, are safe to consume in the small quantities typically found in prepared foods and home cooking. The body processes these small amounts efficiently without causing noticeable changes to the milk supply.
Parents should exercise caution regarding highly concentrated herbal products, such as essential oils, tinctures, or high-dose supplements. These products contain compounds at levels far exceeding those found in culinary herbs, increasing the potential for unintended biological effects. Essential oils should only be used topically or internally after receiving approval from a healthcare provider or lactation consultant.
It is helpful to monitor both the infant and milk output when introducing any new food or herb, especially those with medicinal properties. If a parent notices a sudden, unexplained decrease in milk volume, they can temporarily eliminate the recently introduced herb to see if the supply rebounds. Resources like the LactMed database, which compiles scientific literature on drugs and chemicals in breast milk, offer reliable information on specific herbal substances.