There are a few popular galactogogues, namely shatavari and fenugreek, which contain phytoestrogens. Although I have seen rare mothers complain about a drop in milk supply from these substances, for the most part the response is an increase in supply, if any response at all. According to Dr. Anderson, these weak estrogens block the estrogen receptors in the breasts, thereby competing with maternal estrogens, which are stronger.

A GRAS designation by the US Food and Drug Administration for a certain substance is based on the quantity typically consumed when eaten as a food, and does not pertain to the high amounts taken for medicinal use. Therefore, an herb considered GRAS cannot be considered 100% safe in high quantities.

Even though hops, most typically found in beer, can increase the prolactin level, remember that alcohol can inhibit the oxytocin level. Therefore, beer might have a negative effect on milk supply, depending on how much is consumed.

The National Library of Medicine Lactmed database is an excellent resource for herbal substances as well as prescription medications. This is important to know, since enormous numbers of breastfeeding mothers take supplements to increase their milk supply, improve their energy, or to enhance their diets when they feel that they don’t have time to eat well. Odd reports do occur, such as liver toxicity in premature or young infants, or other major negative effects for mother or infant with certain combinations of supplements. So, it is always worth checking Lactmed for periodic updates regarding any herbal supplements that you tend to recommend to breastfeeding mothers.