
Whether you formula feed your baby from birth or make the switch at some point, you want to make sure to do it properly. Bottle feeding is safe, but that doesn't mean you can let prepared formula sit in the refrigerator for a week before feeding it to your baby. At the same time, it's also not usually necessary to spend hours sterilizing every bottle feeding utensil every day.
Bottle Safety
Polycarbonate plastic bottles contain bisphenol A (BPA), a chemical that, while it can help prevent bacterial contamination of foods, is considered potentially harmful when used for bottle feeding. While research on the effects of BPA on humans is ongoing and not yet conclusive, the
American Academy of Pediatrics (AAP) recommends that parents choose baby bottles that are free of BPA; some plastic baby bottles are labeled as certified BPA-free. Opaque plastic baby bottles do not contain BPA. Glass bottles are also BPA-free, but the potential benefits of using glass are offset by the risk of injury if the bottle breaks. To ensure bottle safety if you do use polycarbonate bottles, which are a hard, clear plastic, do not heat them -- that includes putting them in the dishwasher.
Nipple Safety
Clear silicone nipples are generally preferred over latex nipples for bottle feeding, because they are less likely to cause allergic reactions and deteriorate less quickly. Nipples should be sterilized in boiling water before the first use, but after that, washing in hot water or running through the dishwasher is
considered safe. Replace nipples when they show
signs of wearing out, such as an enlarged hole that allows the formula to gush out, cracking, discoloration or stickiness.
Formula Safety
When bottle feeding, it's important to mix baby formula properly, as the wrong proportion of mix to water will deliver the wrong amount of nutrients to your baby. The easiest way to avoid mixing issues is to buy ready-to-feed liquid formulas, but they are expensive. If you choose the more economical liquid concentrate or powder options, always follow the mixing instructions carefully, using filtered or bottled water. Although most municipal water is very safe (and more rigorously tested than
bottled water), it often contains fluoride as a supplement. After six months, fluoride supplementation in drinking water/formula is
recommended by the AAP, but for those first months, it should be avoided. Sterilizing fluoride-supplemented tap water by boiling will not remove it, and may concentrate it. For formula safety, if you plan to bottle feed exclusively, you may want to invest in a
fluoride water filter. As a formula safety rule, any mixed unused portion should be refrigerated and consumed within 24 (for a powder mix) to 48 hours.
To Heat, or Not to Heat?
Generations of bottle feeding parents have faithfully
heated baby formula. This is not a formula safety requirement; while some babies do prefer warmed formula, your baby may prefer cool or even cold formula, and it's
fine to skip the heating step. If you do heat formula, a
bottle warmer is a good option that's easier than heating the bottle over a double boiler, with more even heating than using a microwave -- a method that is generally not recommended.