Lindsay Modglin is a nurse-turned health and wellness writer with a professional certificate in scientific writing from Stanford School of Medicine.
You’re settling in with a brand new member of the family when you quickly learn about another new parenting frustration. While you expected some of the more obvious struggles—sleepless nights, diaper changes, and spit-up—the seemingly endless collection of dirty baby bottles was not even on your radar.
Yes, washing bottles and pumping components is an obvious necessity in order to kill germs and eliminate buildup from breast milk or baby formula, but it’s important to know that bottles need more than just soap and warm water to keep them clean and sanitary.
They need to be sterilized.
Why is bottle sterilization important?
As parents, we always want what’s best for our little ones. Keeping their bottles free of harmful germs and bacteria is one simple way we can keep them safe and healthy.
Babies’ mouths contain bacteria that are transmitted to the bottle during feedings. This bacteria can multiply rapidly and cause babies to become ill. Additionally, babies are more vulnerable to foodborne illnesses due to their developing immune systems, according to the FDA.
No matter how clean the baby bottles may look, there might still be harmful germs and bacteria present. Of course, washing with soap and water does kill some of the germs, but sterilizing the bottles takes it a step further.
How often should you sterilize baby bottles?
According to the CDC, bottles should always be sterilized prior to the first use, even if taken directly out of the package. After that initial use, they should be sterilized at least once daily for babies less than 3 months old, born prematurely, or with a weakened immune system.
As babies get older and their immune systems strengthen, daily sterilization may no longer be necessary for healthy children.
Hot to sterilize baby bottles
While this may seem overwhelming at first, there are several different methods of sterilization to choose from. You may choose to sterilize the bottles using supplies you have at home or purchase a baby bottle sterilizer. Finding what works best for your family can make this task feel more manageable.
Method 1: Sterilize baby bottles with boiling water
Boiling the bottles in water is one of the cheapest methods of sterilization and requires no additional purchase. Simply disassemble the bottles completely, place them in a pot with enough water to cover all the items, and bring it to a boil. Boil for 5 minutes, or as directed by the bottle manufacturer. Once the specified time is up, remove from the heat and allow the water to cool before using sterile tongs to remove the pieces.
Pros of sterilizing with boiling water
- Cheapest method on the list
- No additional purchase necessary
- No chemicals used
Cons of sterilizing with boiling water
- Nipples tend to degrade quicker with this method, so it’s important to inspect regularly and replace, as needed
- Potential burn risk from the boiling water and steam
Method 2: Microwave baby bottles for sterilization
A microwave steam sterilizer can be purchased for around $15-$40, making it one of the cheaper potential methods. The majority of them can sterilize 4-6 bottles at once. Simply add water and microwave for the specified amount of time, generally around 2 minutes. The power of the microwave will create steam which kills germs and bacteria. You can also purchase steam bags for the microwave, which work in a similar way.
It’s important to follow the manufacturer’s guidelines for specifics regarding the time and power setting. This ensures the bottles are properly sterilized without damage. Once sterilized, the contents will remain sterile for up to 24 hours as long as the lid remains sealed—depending on which sterilizer you use.
Pros of sterilizing with the microwave
- One of the cheapest methods
- Quick—only around 2 minutes for sterilization
- No chemicals used
Cons of sterilizing with the microwave
- Additional purchase needed
- Takes up counter or cabinet space when not in use
Method 3: Cold-sterilization chemicals to sterilize baby bottles
Cold-sterilization tablets provide an option for situations where electricity is not available or when a portable option is needed, such as for travel. Simply fill a container with enough cold tap water to cover the bottles, add the sterilization tablet, and allow the bottles to sit in the solution for the specified amount of time. Cold-sterilization typically takes around 15-30 minutes. The solution can be used for up to 24 hours.
Pros of using cold-sterilization chemicals
- Perfect for situations where access to electricity is not available
- Lightweight and portable
- No risk of burning yourself from steam
- Solution lasts 24 hours
Cons of using cold-sterilization chemicals
- Chemicals are used, which may not be preferred by some
- Ongoing expense to purchase product
Method 4: Dishwasher for baby bottle sterilization
According to the CDC, a dishwasher can be used to sterilize bottles as long as it has a heated drying cycle or sanitizing setting. This helps to ensure that temperatures reach high enough to properly sterilize. While some dishwashers have this capability, others do not. Additionally, it’s important to verify that your bottles and nipples are dishwasher safe.
Pros to using a dishwasher for sterilization
- No additional items needed
- Can be put in the dishwasher along with other dishes
Cons to using a dishwasher for sterilization
- Some dishwashers don’t have a heated drying cycle or sanitizing cycle
- Not all bottles and nipples are dishwasher safe
- Takes longer than other methods
Method 5: Electric sterilizer for baby bottles
Electric sterilizers use steam to kill germs and bacteria. Simply add the amount of water specified by the manufacturer and turn the sterilizer on. Many of these units will automatically move to a drying step and will keep the bottles sterile for up to 24 hours once sterilization is complete.
Pros of using an electric bottle sterilizer
- The quickest and easiest option
- No chemicals
Cons of using an electric bottle sterilizer
- Takes up counter space
- One of the more expensive methods
5 of our favorite baby bottle sterilizers are:
Handling Sterilized Baby Bottles
Regardless of which option works best for your family, it’s important to wash your hands with hot soapy water. You should also take the time to wash anything the bottles will come in contact with prior to handling the sterilized bottles.
It’s also crucial to allow the bottle parts to air dry completely after sterilization. Bacteria thrive in moist environments and could begin to grow in the sterilized bottles, if not dried completely.
- Food Safety Booklet for Pregnant Women | FDA
- How to Clean, Sanitize, and Store Infant Feeding Items | CDC