Can You Mix Breast Milk and Formula?

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Mothers who breastfeed can choose to give their children infant formula for various reasons. If you decide to supplement with formula instead of breast milk, there are a few you should consider. So, can you mix breast milk and formula? It is a question mothers often ask themselves.

It is possible to mix the two, even in the same bottle. But before you do that, you have to follow the mixing instructions carefully. If you combine the improperly, you will have an over-concentration of nutrients that may endanger your baby.

Why should you mix formula with breast milk?

There are various reasons parents would prefer mixing breast milk with formula. Some of these reasons include:

  • Extra sleep: when the mother feeds the baby with pumped breast milk, it gives her extra sleep. The child will feed on the pumped breast milk at night when the mother sleeps.
  • Returning to work: mothers often choose combined breast milk feeding and formula to work out conveniently when they are at work.
  • Low milk supply: other mothers struggle to make enough milk to breastfeed their babies conveniently. When you supplement with the formula, it ensures that your baby gets the nutrition they are supposed to get and gets breast milk.

For whatever reasons, if you decide to give your child breast milk and formula, it comes a time when both have to be combined in one bottle.

Things to consider

Baby formula is meant to provide your baby with a certain amount of calories and nutrients in a specific volume of fluid. For instance, a standard procedure usually is 20 calories per fluid. If you prepare the formula as given, then your baby will get the expected amount.

Nonetheless, suppose you add concentrated liquid formula or powdered formula directly to the breast milk before you dilute it with water. In that case, it will change the balance of nutrients and water in breast milk and infant formula.

When preparing your baby formula, use the precise amount of water and follow strictly the instructions you are given.

How to mix formula with breast milk

Once you buy formula for your baby, typically, you will have one of these three types: concentrated liquid, powdered, ready to feed.

Powdered and concentrated liquid

If you happen to use concentrated liquid formula or powdered infant formula, be aware of making the manufacturers’ guidelines or any alternate instructions that your pediatrician will give you.

First of all, you will have to mix the formula separately from the breast milk. Concentrated and powdered are usually diluted with sterile water or any other safe drinking water boiled for five minutes and cooled.

As per the quality of water in your area and your baby’s health, you can settle for tap water, which will work out well. Again you can consult your child’s doctor to know if the tap water in your area is safe for drinking.

After the liquid is concentrated and the formula is prepared, you can add to the bottle having breast milk or give it after the bottle of breastmilk.

Note that you should never add undiluted powdered baby formula or concentrated liquid formula directly to your breast milk. Again you should never use your breast milk in place of water to mix concentrated or powdered infant formula.

Whenever you have questions about how to dilute your baby’s formula correctly, you should call your baby’s doctor.

Ready-to feed formula

When you compare this, if you decide to add your breast milk into a bottle of ready-to-feed formula, it will be okay to do that. Usually, this type of formula is not concentrated, and so it does not create a risk to your baby compared to other products that need to be prepared first.

Why you should not mix formula and breast milk

Is it recommended that you mix your breast milk with an already prepared infant formula in the same bottle? There are some excellent reasons to offer each one at a time, which will be more considerate?

  • Your baby will get all the aids of breast milk: as breast milk contains many nutritional and health properties than formula, it will be more beneficial if you give your baby all the breast milk available.
  • You do not want to waste your breast milk: If you offer your breast milk, you will minimize the chances of your baby finishing it. It will be wise to allow your baby to finish the milk you have in hand before supplementing formula. It will ensure that your child gets satisfied first before finishing everything you have offered, and you will be tossing extra formula rather than breast milk.

How to mix the formula and breast milk in the same bottle

If you have been wondering if you can combine the formula and the milk in one bottle, the answer is yes! Nevertheless, it is essential that you strictly follow the guidelines required of you.

Prepare the formula first.

Strictly follow the instructions given when preparing this formula and add the correct amount of safe drinking water. After you have mixed your formula with water, you can add breast milk.

Be careful not to use breast milk instead of water as you prepare the formula. Instead, maintain the required ratio of water-to-formula and add breast milk separately. It will ensure you don’t change the natural content of the formula.

When you add excess water into the formula, it dilutes the nutrients. Also, when you add insufficient water will affect the baby’s kidneys and digestive tract, which will later cause dehydration. In extreme cases, this will end up causing neurological problems.

If you are using a ready-to-drink liquid formula, no extra steps need to be taken before combining it with your breast milk.

Ensure safe storage and disposal of breast milk formula.

There are various storage rules, use, and disposal of breast milk formula. Mothers can freeze breast milk in a food-grade plastic container for six months. Once it is unsealed, it can stay in the fridge for 24 hours.

The fridge can keep freshly pumped breast milk in the back of the refrigerator for five days or a cooler insulated for up to 24 hours.

The liquid formula which has been opened should be refrigerated and used within 48 hours. If you made formula bottles earlier, mothers should use them within a day. Likewise, a refrigerated bottle of formula mixed with breast milk should be used and dumped within 24 hours.

When a bottle of room temperature breast milk is good for up to 5 hours, mothers should discard a bottle of formula milk mixed with formula an hour after it starts to use.

Anything that is cow-milk-based, bacteria produce faster in them, and so you should try to save a partially used formula or formula–and–breast milk bottle in the fridge beyond one hour.

Benefits of mixing breast milk with formula

It will be more convenient when you mix breast milk with formula. So there are advantages to this method of combinational feeding.

  • The baby may adjust quickly to taste: if your young one is used to your breast milk, they might not enjoy the taste of the formula. But when you mix the formula, they will learn about this strange flavor more readily.
  • The baby may sleep for longer stretches: it usually takes longer for the baby’s body to process formula. So they might be able to go long periods between if you are using breast milk and formula together.

Risks of mixing breast milk with formula

There are some disadvantages and even risks to mixing breast milk and formula in the same bottle. To make an informed decision, you must be aware of the consequences.

You could be wasting breast milk.

Many might only think of the idea of mixing breast milk and formula in one bottle, worrying that some of the precious fluid could go to waste.

No mother would wish to see the fruits of her pumping labor going in vain. However, the baby might not finish their bottle, so it will be better to give them breast milk first. Then, if they are still hungry, you can provide them with a bottle of formula later.

Your supply may diminish.

When you add formula daily to your routine, it can cause a reduction in your supply of milk.

If you supplement gradually, it can help ensure and maintain an adequate supply.

Health risks

babies should not use breast milk to substitute water when making bottles with powdered or concentrated formula. If you assume using the right amount of water would pose a risk to your baby’s health. Better still, breast milk mixed with formula has a shorter shelf life than breast milk alone.

In conclusion, breast milk and formula are not to be mutually exclusive. Babies can do with all breast milk, baby formula, or a combination of the two. You only have to make an informed decision upholding the safety precautions when preparing the bottles, and with less time, you will have to know how to mix breast milk with formula.

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Hello Moms! I am Alice (Allie). Founder of HerScoop. I am Mom Blogger and Mom of 2 Boys.

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