Is It Safe To Reheat Breast Milk Twice?

Have you ever wondered if you can reheat breast milk more than once? It’s really important to be aware of safety regulations when it comes to feeding a baby, so a lot of mothers question this.

Breast milk should not be reheated twice, no. Reheating it destroys some of the beneficial bacteria in the milk, which your baby depends upon to build a healthy immune system. It also gets rid of nutrients that the baby needs, and could increase the risk of bacterial contamination.

In this article, we’ll look at whether you can reheat breast milk, whether you need to heat it, and how to store breast milk to ensure it stays safe for your little one.

Table of Contents

Can You Reheat Breast Milk More Than Once?

A lot of safety guidelines recommend that you only heat food once, and the same applies to breast milk. Reheating twice it will destroy some of the nutrients that your baby needs in order to grow strong and healthy, and it kills off the beneficial bacteria in the milk. The more times the milk is heated, the less nutritious it will be.

The recommended guidelines for breast milk include:

  • It should only be heated once, and used within 1 hour of being heated (do not put it back in the fridge or leave it on the counter for more than 1 hour)
  • It should be thawed in the fridge overnight, or placed in lukewarm water to thaw
  • Half-drunk bottles should be used within 1 hour, or thrown away, as the baby’s mouth will introduce bacteria that will contaminate the milk
  • Milk should never be heated in the microwave

If you hate waste, it might be tempting to keep unfinished bottles around and see if your baby will drink them later, but you should avoid doing this. You should also avoid reheating milk that has been heated once, as it will not be nutritionally valuable after a second heating. Discard it and pump some fresh milk for the baby.

If you have accidentally left thawed (but not heated) milk out at room temperature, it should be fine for 4 to 6 hours, but should be discarded after this point. Avoid keeping it for any longer, and do not feed it to your baby after the 6 hour mark. Ideally, breast milk should be stored in the fridge until you are ready to use it.

Do You Need To Heat Breast Milk?

Many people think that they need to heat breast milk before they give it to their child, but it is important to be aware that many babies will drink milk at room temperature, and there is no danger associated with this. Babies do not need heated milk, so you can avoid the whole question of reheating by simply giving your baby room temperature milk.

Some babies prefer warm milk, however, and if you’ve just taken the milk out of the fridge, you will need to heat it. Cold milk may be very unpleasant for the baby. This is why a lot of parents choose to heat breast milk for their child – it makes it easier to grab a bottle and go.

If you don’t want to heat the milk, you can just place it on the side about an hour before you wish to feed it to your child. This will allow enough time for the milk to come up to room temperature, which should make it ready for your baby to drink.

When Should You Avoid Heating Breast Milk?

You should not heat breast milk that has already been reheated once, or breast milk that might be unsafe for your child to drink. For example, if the breast milk has been left at room temperature for more than a few hours, it is best to throw it away, especially if the room is warm. Sour or strange-smelling milk should definitely be discarded.

You should also avoid reheating breast milk if your baby is sick. Remember, breast milk contains valuable antibacterial properties that will help your child fight off illnesses, but if you heat it, many of these are lost. You should instead get some fresh milk for your child, so that they can get the maximum benefit and ensure that they fight off infections and diseases.

Being stricter about your food safety routine when the little one is sick is also wise, because your baby will be less capable of fighting off bacteria when their immune system is already low. If your child has a cold, try to use fresh breast milk to help them recover.

Finally, it is best not to reheat breast milk that has been frozen. The freezing process will destroy some of the nutrients and bacteria, and reheating it will do further damage, making the milk considerably less nutritious. If possible, only heat breast milk that has been stored in the fridge, and not frozen.

How Do You Reheat Breast Milk?

It is very important not to warm breast milk up in your microwave. A lot of people do this because it seems like the simplest and quickest solution, but it can be dangerous. Microwaves tend to create hot spots within liquids, and this massively increases the risk of your baby getting burnt on the milk. Milk should only be warm, not hot, when you give it to your little one.

The recommended method involves placing a pan of water on the stove and putting the bottle in the water. You can then heat the water, and the heat will transfer to the milk and warm it. Don’t boil the water, as this will make the milk too hot for the child.

Of course, you should still test the temperature of the milk before giving the bottle to your child. You can use a bottle warmer if you prefer, but this is an extra gadget that many parents find unnecessary.


Reheating breast milk twice is not considered safe, and the CDC advises against doing so. It destroys the nutrients and the antibacterial properties, and compromises your child’s safety. Only reheat breast milk once, and make sure you are following the proper storage guidelines at all times.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *