How to Transition from Formula to Whole Milk

Making the transition from formula to milk is an exciting milestone for both parents and toddlers. Whole milk not only supports healthy growth but also provides essential nutrients that your little one needs in this new stage. Understanding when and how to make the switch can help the process feel smoother and less stressful.

“Milk may provide nutrients that are difficult to get in other places, especially in that age group,” said Ohio-based pediatrican Dr. Elizabeth Zmuda. “Iodine is a big one, and we talk about its relation to cognitive function, and it’s something parents really latch onto. I don’t have to spend as much time convincing them it’s important.”

How to Know if Your Baby is Ready for Milk

Signs your baby may be ready include showing interest in regular foods, drinking from a cup, and guidance from your pediatrician that it’s the right time to start. Every child develops at a different pace, so readiness can look slightly different from one baby to the next.

When to Make the Switch

Here comes the fun part: the actual switch. Most babies are ready to move from formula to milk around their first birthday, once they’re eating a variety of solid foods and no longer rely on formula for most of their calories.

But when it’s time to transition from formula to milk, a gradual approach often works best. Registered dietitian and pediatric nutrition expert Marina Chaparro suggests most babies do best going slowly.

“You may have a timeline, but there’s no set date when you have to start transitioning,” she said. “You may be going back to work, so it really depends on your situation. It’s OK to take it slow.”

Making the Switch

Chaparro created a free online course titled Feeding Toddlers with Confidence that helps ensure a smooth switch. Her suggestions include:

•  Mix is the Fix: Combine whole milk with breast milk or formula. Start with 1 part dairy milk to 3 parts familiar liquid and gradually increase over a week or two.
• Use Whole Milk: Stick with pasteurized whole milk, which provides the fat your toddler’s developing brain needs. “Whole milk is great because all those calories help support cognitive and neural development,” Chaparro said.
• Offer it in a Cup: “We’re not just switching the milk – we’re also changing the way it’s offered,” Chaparro said. “This is a great time to wean off the bottle, and this shift can help babies understand this is a new phase.”
• Build Familiarity Early: If your baby has already had dairy in solids (like cheese or yogurt), the taste of milk won’t be totally new.

“We just don’t want to do it cold turkey,” Chaparro emphasized. “It’s a new taste, a new texture, and even a new way of feeding. It helps to take it step by step.”

 And while constipation may be a common concern, the transition itself usually isn’t the cause.

 “Constipation is more about not getting enough fiber or fluids,” explains Megan Maisano, senior director of nutrition and regulatory affairs at National Dairy Council. “It’s more common during potty training, but it can happen at any age.” 

To prevent constipation, focus on serving a variety of fiber foods like fruits, veggies, and whole grains, and for toddlers over 12 months, remember this helpful phrase: “Milk with meals, water in between.” 

How Much Milk Should a 1-Year-Old Drink?

After turning 1, most toddlers should aim for about 16 ounces of whole milk per day – roughly 2 to 4 small cups. 

That’s enough to support their calcium and vitamin D needs without crowding out other nutrients. “Too much milk can fill them up and interfere with iron absorption,” Zmuda warns.

Pro tips:

• Spread milk across meals and snacks
• Don’t stress over daily exact ounces – look at overall nutrition
• Combine milk with solids like oatmeal or smoothies to add variety

“Starting at age 1, the beverage choices get pretty simple,” said Maisano. “Just water and plain milk. One less thing for parents to worry about!”

Moo-ving to Milk with Confidence

If you’re feeling unsure about making the switch to milk, you’re not alone. “So many parents ask me, ‘Am I doing this right?’” Chaparro said. “There’s a lot of fear and confusion out there. My job is to cut through the noise and remind parents: You’re doing great.”

Whether your baby breastfeeds, takes formula, or both, you’ve made it through an incredible first year. Moving to cow’s milk is just the next step in that journey.

Remember: there’s no “perfect” way to do this. Start when your child is ready, go at your own pace, and if you have questions, ask your pediatrician. They’ve seen it all and are there to help, especially in these times of message overload.

“There’s so much marketing out there, it’s hard to know what’s accurate,” Zmuda said. “Parents are often influenced by societal beliefs about what’s ‘good,’ and it takes time to help them get a balanced perspective. Much of my work is myth-busting and setting the record straight.” 

So, in a world full of noisy “must-do” advice, be guided by expertise and don’t second-guess yourself. You’ve already made countless thoughtful choices in your baby’s life. 

This milk transition? 

It’s just one more hurdle you can clear – spit up and all.