Caffeine boosts energy & mood & makes you more alert. That’s helpful in the morning & when you need to work. More is not always better: too much can push you over the line from alert to jittery and anxious.
Caffeine passes from the mother to infant in small amounts through breast milk, but usually does not adversely affect the infant when the mother consumes low to moderate amounts. Ingesting up to 300 mg of caffeine/day (about 2 to 3 cups of coffee) while breastfeeding appears safe for mothers & infants. Caffeine appears in breastmilk rapidly after maternal ingestion.
Excess caffeine intake may lead to infant sleeping issues & restlessness. If an infant appears to be more fussy or irritable after the mother consumes caffeine, she should consider decreasing her intake. Preterm & younger newborn infants break down caffeine more slowly & may have serum levels of caffeine similar to mother’s level, so mothers of these infants might consider consuming even less caffeine.
Irritability, poor sleeping patterns, fussiness, & jitteriness have been reported in infants of mothers with high intakes of caffeine (up to 10 cups of coffee per day.)
LactMed (the Drugs & Lactation Database at NIH.gov) describes 20 studies of maternal caffeine intake with measurable caffeine levels in mother’s breastmilk & baby’s blood. Peak effect occurs one hour after mother’s caffeine dose, with effects lasting about 6 hours. Detectable amounts in breastmilk range from 7 to 15% of maternal weight-adjusted dose.
Dietary sources of caffeine in milligrams (mg) include:
Coffee – one cup ~ 150 mg
Green Tea – 8 oz ~ 28 mg
Black Tea – 8 oz ~ 47 mg
Iced Tea – 8 oz ~ 25 to 48 mg
Soda – 12 oz ~ 34 to 54 mg (for diet & regular sodas)