Drank reverse osmosis water when pregnant and now breastfeeding. am i depriving my baby of any nutrients or minerals?

Perhaps Fluoride: Generally, everything a baby needs is in breast milk, and your body will sacrifice what you may need to make sure the baby gets what (s)he needs. But, if you are not taking in enough Fluoride in your diet, then your baby is not getting any either. Please check with a dentist about any recommendations regarding Fluoride and babies.