June 1, 2021

Feeding Your Infant: How to Prepare and Store Baby Formula

Get the 101 on formula, from preventing illness to ensuring your child gets all the nutrients

mother making baby formula in bottle

You decided on a formula and bought a set of baby bottles — and now it’s go time. But what exactly do you do? Pediatric dietitian Andrea Adler, RD, CSP, CSPCC, LD, explains the ins and outs of preparing and storing baby formula.

Advertisement

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

How do you prepare powdered baby formula?

For many parents, formula is essential in the first year of feeding their babies. So learning how to make baby formula is a crucial skill. It’s not hard, but it’s important to follow a few guidelines:

Use the correct formula-to-water ratio

Always follow the directions on the container for how much formula and water to use unless your pediatrician or pediatric registered dietitian recommends otherwise.

  • Make sure it’s a full, leveled-off scoop, says Adler. But read the label: “The directions on some formulas say to pack the scoops while others say to use an unpacked scoop.”
  • Use the scoop that comes in the container. This helps you nail the right formula-to-water ratio. Scoops can vary in size from formula to formula.

Avoid bottled water

You might be surprised to learn that tap water is usually the best water to use with formula. “Tap water is safe to use for mixing with infant formula,” reassures Adler. “It contains fluoride, which is beneficial for teeth even before they start to show above the gums.” Have a home filtration system? That’s OK since fluoride typically remains in the tap water after being filtered.

On the other hand, distilled, purified, deionized or demineralized water doesn’t contain fluoride. Plus, bottled water isn’t sterile, says Adler, except baby or nursery water, which has been boiled before being bottled. Bottled water also can become contaminated if it sits on the shelf too long.

Note: If well water comes through your tap, make sure it’s tested regularly for safety through the local health department.

Never use the microwave

There’s no need to heat formula. According to Adler, there’s no harm in giving your child formula that’s cold or room temperature. But if you do want to warm it up, avoid putting formula in the microwave. Uneven heating can create scalding spots that can burn your baby’s mouth.

The best way to heat formula is by using a store-bought bottle warmer or placing the bottle in a bowl of hot water. These methods gently heat the formula. But it’s a good idea to test how hot it is before giving it to your child. Let a few drops fall on your inner wrist. If it’s a comfortable temperature, it’s ready for your little one.

Advertisement

Do I need to used boiled water to make formula?

As long as your child is healthy, you don’t need to boil the water, states Adler. But if it gives you peace of mind, go ahead. Just make sure the water cools completely before mixing it with formula so as not to burn or scald the caregiver or the baby. Boiling hot water also can break down some of the nutrients in formula.

Should bottles be sterilized?

Washing bottles with soap and water removes germs, but exposing them to high heat (sterilizing) takes it one step further. “I do recommend sterilizing bottles and nipples before using them the first time,” Adler says. “But after that, thoroughly washing them with soap and water is fine.”

However, if your child has a compromised immune system or was born prematurely, you may need to regularly sterilize their bottles. Ask your pediatrician if this step is necessary for your child.

There are a couple of ways to sterilize bottles. The cheapest route is to place them in boiling water for five minutes. But you can also purchase a bottle sterilizer, which uses steam to kill germs.

If you have questions about what bottles to use, read what a pediatrician says about the safety of plastic bottles and other alternatives.

How long does formula last after being prepared?

Generally, you want as little time as possible between preparing the bottle and feeding it to your child. Any prepared formula — mixing powder or concentrate with water or opening a ready-to-feed formula bottle — can sit out at room temperature for two hours. After that, you should feed it to your baby or refrigerate it, says Adler.

In the fridge:

Advertisement
  • Unused but open ready-to-feed bottles can stay up to 48 hours.
  • Unused bottles made with powdered formula can stay up to 24 hours.

Can I prepare formula in advance?

It’s best to make the bottle right before giving it to your child. But that can be a hassle in the middle of the night.

“During the daytime, I recommend that you make the bottle roughly before you’re going to feed it,” Adler says. “But for overnight feeds, it’s convenient to make bottles up before you go to bed and put them in the fridge. They’ll stay good for 24 hours, so you can quickly grab one at 3 a.m.”

Can I store formula leftovers in the fridge?

Toss leftover formula. Once you’ve started feeding your baby from the bottle, the formula is good for just one hour. That’s because the baby’s mouth introduces bacteria to the nipple.

“It’s like how you wouldn’t want to take a sip of milk, let it sit out a couple of hours and then drink it again or put it in the fridge for later. The risk of spoilage is too high,” explains Adler.

How long is stored formula good for?

The unopened formula you have sitting in your pantry is good until the expiration date on the cans or ready-to-feed bottles. Once opened, powdered formula lasts one month. After that time, formula makers can’t guarantee nutrition quality. It’s best to start with a fresh can.

Bottle-feeding is one of the many skills new parents have to learn, but within no time, you’ll be a pro. With these tips in mind, you can keep your little one safe, nourished and healthy.

Related Articles

Close up of hand holding a scoop of powder baby formula over container of powder baby formula
February 23, 2024
Feeding Your Baby: How and When to Supplement With Formula

When breastfeeding doesn’t go as planned, you may need to supplement with formula or donor breast milk — and that’s OK

Baby formula being scooped out of a container
May 30, 2022
What Should You Do About the Baby Formula Shortage?

You should never make your own infant formula, and here’s why

A person sits at a table with food and feeds their baby with a spoon
September 20, 2021
How to Tell if Your Baby is Ready to Stop Drinking Formula

And how to wean them off formula when it’s time

person holds small baby to their chest
June 15, 2021
What Are Your Formula Options for a Gassy Baby?

A different formula may help babies with gas or other digestive problems — find out which one may be best for your baby.

1 year old drinking milk from bottle
December 3, 2020
When Is It Safe to Give Cow’s Milk to My Baby?

The short answer from a pediatrician

Sad, exhausted parent holding newborn in cage surrounded by drug addiction possibilities
February 15, 2024
Can Babies Be Born Dependent on Drugs?

Neonatal opioid withdrawal syndrome, or NOWS, can develop when a birthing parent uses opioids, nonmedical drugs or even some prescription drugs during pregnancy

Baby in onesie asleep on back
February 12, 2024
When Can I Put My Baby To Sleep on Their Stomach?

Your baby needs to able to roll in both directions before they can make the switch

parent holding baby at a doctor's appointment
February 8, 2024
How Many Bones Do Babies Have?

Surprise: A lot more than adults!

Trending Topics

White bowls full of pumpkin seeds, dark chocolate and various kinds of nuts
25 Magnesium-Rich Foods You Should Be Eating

A healthy diet can easily meet your body’s important demands for magnesium

Woman feeling for heart rate in neck on run outside, smartwatch and earbuds
Heart Rate Zones Explained

A super high heart rate means you’re burning more than fat

Spoonful of farro salad with tomato
What To Eat If You’ve Been Diagnosed With Prediabetes

Type 2 diabetes isn’t inevitable with these dietary changes

Ad