Motherhood has a lot of rules — and moms aren’t just making them, they’re following them. Particularly when it comes to breastfeeding, we hear more about the “don’ts” than the “dos.” Don’t take allergy medicine! Don’t touch that sushi! But how much science is backing these rules? What should you avoid, what’s okay to have in moderation, and what rules are flat-out myths? Sharman L. Reed , MD, an OB/GYN at Kaiser Permanente, says that there are fewer things to avoid when breastfeeding than when pregnant. “While you’re pregnant, you’re sharing a blood supply with your baby,” Reed says. But in breastfeeding, you’re effectively just making a smoothie for your baby. Less is being converted over that goes in the baby’s gut.” The World Health Organization recommends new moms breastfeed for up to six months , but when to stop (and whether you do it at all) is ultimately a personal choice.