Vital Signs 🫀 on Instagram: "Is Your Coffee Making Your Baby Fussy? . . Contrary to a total ban, moderate coffee intake (200-300mg of caffeine, or about 2-3 cups) is generally considered safe while breastfeeding. The concern isn't the coffee itself, but the caffeine. While only a small amount (~1.5%) passes into breast milk, newborns and premature infants metabolize it extremely slowly. This can cause caffeine to accumulate in their system, leading to irritability, jitteriness, and poor sleep.