Is Dill safe while breastfeeding?

Summary of use during breastfeeding

Dill (Anethum graveolens) seeds contain essential oil rich in carvone and limonene, in addition to phenolics, such as trans-anethole, and flavonoids. Dill is a purported galactogogue.[1-6] No scientifically valid clinical trials support this use, and one small, old study found no galactogogue effect of a primary dill component, d-carvone.[7] Dill is one component of an herbal mixture that showed some evidence of galactogogue efficacy.[8] Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[9,10] Two studies found small, but measurable amounts of d-carvone in the milk of mothers given the chemical experimentally. Dill is "generally recognized as safe" (GRAS) as a food by the U.S. Food and Drug Administration. It is generally well tolerated, but occasional allergic skin reactions have been reported, especially after contact with fresh dill. In two studies, nursing mothers were given d-carvone. No adverse effects were noted in the mothers or infants.

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Effects on the breastfed infant

A study compared 3 groups of women. One group of 20 nursing mothers consumed 30 mg of d-carvone in 75 grams of hummus every third day for 28 days (10 exposures) at about 2 hours before a "usual" nursing time. A second group of 20 nursing mothers followed the same regimen, but their hummus contained no d-carvone. A third group of 8 mothers received the d-carvone flavored hummus, but were exclusively formula feeding their infants. After this 28-day period, both groups of breast-fed infants showed greater acceptance of d-carvone-flavored mashed potatoes than the formula-fed infants who preferred the unflavored potatoes. The authors interpreted these results to mean that breastfed infants are more receptive to a wide array of flavors than formula-fed infants.[7]

Effects on milk supply

A convenience sample of 60 women whose infants were admitted to the neonatal ICU were given either nothing (n = 30) or dill seeds tea (containing 1 tablespoon of dill seeds, 200 mL of water, 1 tablespoon jaggery (unrefined sugar), and half a tablespoon of cow ghee) daily in the morning for 5 days. Mothers responded to a questionnaire related to suckling sufficiency using a Likert scale. A statistically significant improvement in lactation was reported among the women given the dill seed tea.[5] However, the lack of randomization, blinding and a placebo control diminish the validity of this study.

A commercial preparation containing wild asparagus 2 grams, dill 1.5 grams, cumin 1 gram, and cardamom 0.5 grams (Ayush-SS granules, Central Council for Research Ayurveda & Siddha, India) per dose was studied in a randomized double-blind trial in Indian mothers whose infants were experiencing “insufficient lactation”. This dose was given twice daily for 12 weeks beginning when full-term infants failed to regain their birth weight by 14 days postpartum, exhibited a weight gain of less than 20 grams daily between days 15 and 90 of life, or had fewer than six urinations per day. A per-protocol analysis (dropout rate 22%) found that at six months, 74 of 106 (70%) infants in the Ayush-SS group were exclusively breastfed, compared to 47 of 105 (45%) in the placebo group. After 90 days, 81 of 106 infants (77%) in the Ayush-SS group gained at least 20 grams per day compared to 44 of 105 (41.8%) in the placebo group. Maternal perceptions of insufficient lactation were lower in the Ayush-SS group (15% vs. 58%). All of these differences were statistically significant. No severe adverse events related to the intervention were observed.[8] The study was well designed and performed, but no intent-to-treat analysis was performed.

Levels in milk

Maternal Levels. Twenty mothers consumed 30 mg of d-carvone in 75 grams of hummus every third day for 28 days (10 exposures) at about 2 hours before a "usual" nursing time. Breastmilk samples were obtained 2 hours after ingestion on the first and last days of carvone intake. Carvone was detectable in the milk of 18 mothers. Average carvone concentrations in breastmilk were 2.5 mcg/L and 3.8 mcg/L on the first and last days of sampling, respectively. However, these values did not differ statistically, and the combined average carvone concentration was 3.2 mcg/L. A control group of 20 women who did not ingest d-carvone had no detectable carvone in their breastmilk.[7]

Eighteen lactating women were given 100 mg of d-carvone mixed with lactose and talc in a capsule on 3 test days. Milk samples were collected every 2 hours for 8 hours starting at the time of ingestion. Carvone was detected in milk at all collection times, with the average concentrations of 1.3 mcg/L at 0 hours, 7.2 mcg/L at 2 hours, 5.6 mcg/L at 4 hours, 4.3 mcg/L at 6 hours and 2.7 mcg/L at 8 hours after the dose. The average peak carvone concentration in milk was 10.5 mcg/L. Carvone metabolites were not detected in any milk samples.[11]

Infant Levels. Relevant published information was not found as of the revision date.