Baby Bottles 101: Here’s How Many (and What Kind) You Need

“Baby bottle” is probably one of the many baby-related decisions you know you have to make as a parent. Whether you just brought your baby home, are weaning them off breast milk or planning a return to work, the bottle you choose will become a big part of their routine (and yours).

How many bottles do you need? And what kind should you get? Deciding what’s best for you and your baby can initially be overwhelming, but it doesn’t need to be.

Pediatrician W. Kyle Mudd, DO, offers reassurance on your baby bottle dilemmas and shares tips on how to make the best choice for you and your child.

How many bottles do I need? 

Your little one will need more than one if you choose to bottle-feed. But how many, precisely?

During the first month of their life, your baby won’t eat at the same rate you do (breakfast, lunch and dinner). Instead, they’ll need to be fed every two to four hours or so. As they hit 2 months, 4 months and so on, that range will expand to three to four hours and four to five hours. Because of this, you’ll want to have a good supply of bottles at the ready.

Your baby bottle stock will also depend on whether you’re mostly bottle-feeding or breastfeeding (chestfeeding). If you’re completely or mostly bottle-feeding, it’s recommended that you have eight to 10 bottles. If you’re usually breastfeeding, then you’ll need fewer, around three or four.

Different types of bottles for newborns

The world of baby bottles ranges far and wide. Here are some options you can choose from:

Plastic

Plastic bottles are made from a specific plastic called polypropylene. Their main advantage is that they’re light while still heavy-duty, so they’re not likely to break while you’re juggling them and your baby on each arm. But there are some concerns around using plastic with your little one

Are plastic baby bottles safe?

The science of plastics and health is a little fuzzy. Many ingredients in plastic haven’t been thoroughly tested in people. Much of what we know comes from studies in non-humans.

“We don’t know exactly how all of these compounds affect human health,” Dr. Mudd says. But there are hints that compounds in plastics may be related to health problems.

One of the biggest concerns for baby bottles has been bisphenol-A (BPA), which are chemicals used to harden plastics. As chemicals can imitate the body’s reproductive hormones, they may affect fertility and the timing of puberty. Evidence from a 2018 report showed that they may also increase body fat and affect your nervous and immune systems.

Back in 2012, parents breathed a sigh of relief when the U.S. Food and Drug Administration (FDA) banned BPA from plastic baby bottles and sippy cups. But BPA may not be the only concerning ingredient in plastic baby products.

A study in 2022 found that other chemicals like polypropylene (PP) and polyethersulfone (PES) can be found even in BPA-free products. According to the study, some of these particles were common in drink bottles, including baby bottles and sippy cups, while others were traced back to food product packaging.

A 2020 study showed bottles made of polypropylene shed millions of plastic particles into the liquid they contain. When babies drink from those bottles, they ingest the so-called “microparticles,” too.

“Even a BPA-free plastic bottle has some risk,” adds Dr. Mudd. “But you can take steps to limit risk as much as possible.”

Managing risks around plastic baby bottles

While it’s helpful to be aware of the risks, Dr. Mudd cautions to try not to lose too much sleep over your baby’s plastic bottles. (Let’s face it, if you have a baby at home, you’re losing enough sleep as it is.)

“The nutrition your child gets throughout childhood is likely much more important than what kind of bottle you use,” he points out.

In the meantime, you can balance the risks of plastic with reasonable precautions:

• Steer clear of high temps. Heat causes plastics to shed more chemicals and particles, so avoid high-temperature situations. Skip the dishwasher and clean bottles by hand in warm (not hot) soapy water. And don’t ever heat plastic bottles in the microwave.
• Store milk smartly. To minimize exposure to plastic, don’t store formula or breast milk in plastic bottles. Keep it in a glass container in the refrigerator or freezer, and pour it into the bottle just before feeding time. (Discard any leftovers that your baby doesn’t finish during that meal.)
• Don’t shake. Vigorously shaking a bottle can cause more microplastics to flake off into the liquid. If you need to shake up formula to mix it, do so in a glass or stainless-steel container before transferring it to the plastic bottle.

Glass or stainless steel

Glass and stainless-steel bottles and sippy cups are another great option for parents. They’re safer from a chemical standpoint, Dr. Mudd says. They also last a long, long time and you can boil them in water to ensure a deep clean.

But they do have some drawbacks. Glass is breakable, of course, which can be a concern with baby’s little fingers (or, for that matter, an overtired parent’s clumsy fingers). Glass and metal products may also be more expensive, so they’re not an option for everyone.

Hybrids

You can also try a hybrid bottle that combines the best of both worlds. Hybrid bottles have an inner glass liner that prevents chemicals from mixing into the formula. At the same time, they’re plastic on the outside, keeping them sturdy and unbreakable. As you may have guessed, these double-layered bottles tend to be more expensive. 

How long do baby bottles last and are they reusable? 

While baby bottles don’t last forever, you can reuse them. But just like everything we use, natural wear will happen. In general, if you notice any discoloration, cracking or leaking in your bottle, then it’s time for a new one. Otherwise, you can replace your baby bottles on a schedule, based on the type you have:

• Plastic baby bottles: Replace them after three to six months. Because of the plastic used, these bottles are more prone to scratching or wearing out over time. 
• Glass baby bottles: These can typically last even longer. If handled properly, they’ll probably last several years. Glass bottles can handle high temperatures without degrading.

As for replacing the nipples, this will largely depend on your baby and what size you’re using. Look for signs that it’s time to switch it out: Is it starting to look flattened? Are there any tears, cracks or discoloration? Do you notice any residue that isn’t coming off during washing? If so, it may be time to switch to a new one.

Do you need to sterilize baby bottles?

According to the U.S. Center for Disease Control and Prevention (CDC), baby bottles should be cleaned after every feeding — including the caps and nipples.

But should you be sterilizing them, too? It’s generally recommended that you should always sterilize your bottles right after buying them (yes, even before you use them). And if your baby is less than 2 months old, was born preterm or has a compromised immune system, the CDC recommends sanitizing their bottles and nipples daily.

Otherwise, as long as you’re washing after each use, you can choose to sanitize less frequently or not at all. Talk to your child’s pediatrician if you’re not sure.

How to clean and sterilize baby bottles

Plastic bottles

If you use plastic baby bottles, here’s how you should wash them:

1. Disassemble the bottle. Remove all parts, including the nipple, collar and any other removable parts.
2. Rinse. Rinse each part under warm (not hot) running water to remove any milk residue.
3. Soak. Fill a basin or the sink with warm water and a small amount of mild dish soap. Place all bottle parts into the soapy water and let them soak for a few minutes.
4. Scrub. Use a bottle brush to clean the inside of the bottle thoroughly. Ensure you reach the bottom and all sides. Use a nipple brush to clean the inside of the nipple, if you have one. Ensure all milk residue is removed from the tiny holes.
5. Rinse soap off. Rinse all parts thoroughly under warm running water to remove any soap residue.
6. Dry. Place the cleaned parts on a clean dish towel or drying rack to air dry. Avoid using a dish towel to wipe them dry, as it may transfer germs.

You may wonder if you can further sanitize your plastic water bottle by boiling it, but this isn’t recommended. “Heat causes plastics to shed more chemicals and particles, so avoid a high-temperature situation,” explains Dr. Mudd. In the case of glass bottles, you can use a bit more heat to disinfect them.

Glass bottles

If you use glass baby bottles, here’s how you should wash them:

• Put them in a pot or pan of water, making sure they’re completely covered.
• Let the water come to a boil.
• Wait about five minutes for the bottles and nipple caps to boil.
• Afterward, remove the bottles into a sink or clean bowl.
• Use soap and water to wash them as you usually would.
• Finally, lay the bottle and nipples out on a clean towel and allow them to dry.

Takeaways 

Choosing the right baby bottle can be a big part of your journey as a parent. Pick the bottle that works best for you and your baby, ensure you’re cleaning them correctly, and enjoy this special feeding time with your little one!