Why do you have to sterilize baby bottles?

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Sterilizing baby bottles has become a common practice in recent years.

Many parents believe that it helps prevent infections and illnesses in babies.

It is a process where bacteria or germs are killed off using heat, chemicals, radiation or other methods. 

There are various methods to sterilize the bottles.

We shall discuss them later in this post.

The main reason why we sterilize baby bottles is because of the risk of infection from harmful bacteria which can be found on the surface of an unsterile bottle.

These bacteria include E-coli, Staphylococcus aureus.

However, there are many benefits to sterilizing your own baby’s feeding equipment.

It allows you to be more involved with your child’s nutrition as well as making sure they are getting the best possible start to life.

When you have small children, especially infants, you need to be extremely careful while feeding them.

Their immune systems are not yet developed and they can get infected very easily with what you feed them.

One of the main things you need to do is to sterilize baby bottles ( if you are bottle feeding ) and this article tells you all about why you must sterilize them and also answers a lot of other questions about this topic

Feeding infants with contaminated bottles may be one of the most important pathways for transmitting enteric pathogens during infancy.

It can cause infants to have stunted growth which is a serious problem.

Stunting is not only a major risk factor for childhood morbidities, but also carries lifelong consequences including cognitive impairments and reduced economic productivity.

Infants who are fed with breast milk are less likely to develop diarrhea and asymptomatically infected enteric bacteria than bottle-fed infants.

Studies have shown that high levels of fecal bacterial contaminants have been found on bottles and nipples.

These studies have identified enteropathogenic Escherichia coli and Staphylococcus aures as the most common bacteria.

Bacterial outgrowth is facilitated by the tendency for formula or milk to become an ideal breeding ground for bacteria and by the difficulty of effectively cleaning bottles.

Germs and bacteria are also contained in your water supply.

They also grow around baby  leftover formula in the bottles/ nipples or not properly refrigerated.

Hence your baby bottle can contain a lot of bacteria and if you are feeding your child with them, you are making them ingest a lot of this infected feed.

If you don’t sterilize your baby bottles properly then you could give your child food poisoning which can lead to vomiting, diarrhea, stomach cramps and headaches. It can also affect their brain development.

So if you want to avoid giving your baby health issues such as food poisoning then you really need to sterilize the bottles.

You must sterilize bottles ( and other feeding equipment ) at least till your infant is 12 months old ( you can initially do it for 6 months )

How To Sterilize Your Baby Bottle

Before sterilizing, you need to do the following:

  1. Wash bottles, nipples, and other feeding equipment with soapy water immediately after each feed.

2. To clean bottles, use a clean bottle brush.

3.To clean teats, use a small bottle nipple brush. You can also turn nipples inside out then wash them with soap and hot water.

4. Salt should not be used when cleaning the nipples as these could be harmful for your baby.

5. You can clean your baby’s feeding equipment by putting it in the dishwasher ( first check if they are dishwasher safe) . Putting feeding equipment through a dishwasher will clean it, but it won’t sterilize it. Make sure bottles, caps, lids, and nipples are facing down. If you want to be sure that your baby’s teats are completely clean, you might prefer to wash them separately by hand with hot water.

Before sterilizing, rinse all your equipment in clean cold running water.

You must dry them with a clean towel.

There are various ways to sterilize your baby‘s feeding equipment. 

Here are some popular ways for Baby bottle sterilization :

With Cold water sterilising solution 

Cold water sterilising solution (CWS) is a chemical compound that kills microorganisms by dissolving them into tiny particles. It is usually made up of sodium hypochlorite, ethanol and water.

It comes in tablet form or powder form.

It is important to note that CWS cannot kill viruses and does not remove dirt or stains. However, it is effective at killing most types of bacteria/ harmful germs and fungi.

To use CWS, simply fill a clean container with hot clean water and add 1 part bleach to 9 parts water ( or as specified by the manufacturer ).

Stir well until all the ingredients are dissolved.

Once the solution is ready, pour it into the baby bottle and allow it to cool before filling with formula.

Pick the bottles up with clean hands and store them.

With steam 

Steam sterilization is a method of killing microorganisms by exposing them to saturated steam at 121°C (250°F).

It is widely used in hospitals and laboratories to kill all types of microorganisms, including viruses, bacteria, fungi and spores.

Use  reputed and reliable Baby bottle steam sterilisers ( preferably an Electric Bottle Sterilizer ).

Sterilization kills microorganisms by damaging their cell membranes.

When the temperature drops below 60°C (140°F), the cells begin to repair themselves.

However, if the temperature rises above 140°C (284°F), the damage becomes permanent.

This means that once the temperature drops below 60 °C (140°F) again, the microorganism cannot survive.

The most important thing to remember when using a steam sterilizer or microwave sterilizer is that they should never be left unattended.

Always ensure that the door is locked before leaving the room and that the lid is securely fastened.

Never leave the unit unattended during operation.

Do not allow any food or drink into the area around the machine.

Never put anything directly onto the heating element.

Never touch the control panel or dials.

With Boiling Water

Boiling is a simple method of sterilization. It kills bacteria by heating the water inside the bottle to a temperature of 121°C (250°F).

To boil a bottle, fill it with hot tap water and leave it until it reaches the desired temperature.

Once the water has reached the correct temperature, remove the bottle from the heat source and let it cool down before rinsing it thoroughly.

You should always follow the manufacturer’s instructions when sterilizing baby bottles. If you are unsure about how to sterilize a bottle, check the label.

It is important to note that sterilized bottles may not be suitable for all types of baby food. Some foods require a specific temperature range to ensure they remain safe.

Some manufacturers recommend that you avoid storing boiled bottles in direct sunlight. This is because the UV rays can cause the plastic to break down.

If you are concerned about the safety of your baby’s food, then you should consult your doctor before sterilising any bottles.

How Long Should I Keep My Baby Bottle Sterile?

To avoid any risk of illness, it is recommended that you sterilize your baby bottles at least till the baby is six months old. However, if you find that your baby is suffering from frequent colds or ear infections, then you may wish to sterilize your bottles for another 6 months.

It is important to note that the sterilized bottle does not mean that the bottle is free from germs. In fact, the sterilization process only kills off bacteria, so it is still possible for your baby to pick up germs from the bottle.

How often should you sterilize your baby bottle?

You should sterilize your baby bottle after each feeding. If you feed your baby every four hours, then you should sterilize your bottle every four hours.

However, if you feed your baby every eight hours, then you should change your baby bottle every eight hours.

If you are unsure whether you should sterilize your baby bottles more frequently, then you should consult your doctor.

How long do bottles stay sterile once removed from the sterilizer?

A study by the University of California at San Francisco found that most bottles were still safe to drink within 12 hours of removal from the sterilizer. However, if they were left in direct sunlight, they could lose their sterility in less than four hours.

So what does this mean for you? If you leave your baby bottle in direct sunlight, it may not be safe to drink. But if you keep it in the fridge, it should remain sterile for up to 12 hours.

How To Clean Up After Using a Baby Bottle?

It is important to clean up after using a baby bottle.

If you don’t, then you may end up spreading germs around your house. Here’s how to clean up after using baby bottles.

  1. Wash hands thoroughly before handling any baby bottles.
  2. Use warm water and soap when cleaning baby bottles and bottle parts/ bottle attachments
  3. Rinse the bottle under running water.
  4. Dry the bottle completely, especially the nipple with a clean towel.
  5. If you’ve used the bottle to feed your baby formula, then rinse it under running tap water until all traces of milk are gone. Dry the bottle thoroughly and store it in a safe place.
  6. If you’re going camping, then bring along a small dedicated bottle brush. Brush the inside of the bottle regularly to remove any leftover residue.

What are CDC guidelines for cleaning and sanitising Infant feeding equipment

As per the Centres for Disease Control and Prevention ( cdc ) here is a detailed guideline on how to handle equipment and items that you need for feeding your infannt

How To Make Sure That Your Baby Bottle Has Been Sterilized Properly

meta description: When you’re bottle feeding your baby, you’ll need to sterilize all of their bottles. Learn why you should sterilize baby bottles here.


Carrie Walters
Carrie Walters is a young mother of Nina and Tom, who along with her husband Jake is passionate about helping moms and families find modern solutions to common parenting and lifestyle questions. Together with a team of real moms and medical experts, this young couple share sound advice and proven tips to help make your life easier. They manage this blog along with other blogs and Youtube channels on similar topics