Often new parents are nervous about mixing and matching infant formula they offer their babies. They worry if they switch from one formula brand to another, they may cause their baby fussiness, stool changes, upset or worse–that they could put their baby at risk.
It’s safe to mix and match infant formulas if you are following standard mixing instructions. Really.
Although spitting up or gassiness is usually not due to the protein in formula (cow’s milk versus soy versus hypoallergenic), sometimes changing formula helps new babies and their parents who worry. Switching them up can even help clarify worries in some scenarios when a parent worries about excessive gassiness, intolerance, or significant urping or spitting up.
Experimentation with formula brands in an otherwise healthy newborn is okay. But it’s not necessary at all, either.
It’s fine to make a bottle that is ½ formula from the blue can and ½ formula from the yellow one. Fine to serve Simulac one week, Enfamil the next, Earth’s Best or Goodstart followed by Soy formula the following day. Fine to buy one brand that’s on sale only to buy the other brand next week.
However, all this being said, I usually recommend families don’t switch often. Let time unfold and give your baby a chance to settle in. Don’t react to every single poop. Give your baby a week or two on a formula before you give up or reach for a new can.
Recently one of my best friends found that when she served her baby organic formula he got constipated but when she used non-organic, he didn’t. She was determined to provide him as much organic food as possible but really hated seeing him strain to poop.
This is where Goldilocks come in. She texted me one night assuming that she couldn’t mix and match formulas, but “just wanted to check and see.” I felt she could. Viola! She found that making the “just right” formula (1/2 organic mixed with a ½ conventional) provided a bit more balance for her newborn son. She found that when she fed him the Golidlocks bottle, the hard stools and potential constipation improved.
Fine by baby. Fine by pediatrician. Mama Bear felt better, too.
Parents often want to buy the formula on sale; they wonder can they switch it up and save money? I say yes. There is no danger in providing your baby differing formulas from one day to the next.
Think of it this way: babies who are breast-fed have a slightly different milk each and every meal due to mom’s variant diet. Although fat, calories, and protein count remain constant, flavor and variety changes. A slightly different recipe at every feed.
Goldilocks Infant Formula Rules:
- Never add sugar or juice or cow’s milk to infant formula.
- Don’t fix what isn’t broken. No need to switch formula if no concerns.
- Don’t dilute or concentrate the formula you make for your baby. Standard powdered formulas usually mix 1 scoop to every 2 ounces of water. Follow directions and use the scooper that comes with the formula.
- In the US, in my opinion it’s safe to use tap water to mix infant formula. However, some families may want to avoid excess fluoride consumption from tap water for babies exclusively formula fed. Here’s info from the CDC on fluoride for formula feeders. No need to purchase distilled water (in plastic bottles) and no reason to boil water prior to mixing either–if you want, you can remove fluoride with a reverse osmosis filter system.
- If your baby is super cranky, doesn’t react well to a change in the formula you offer, or you’re worried about a potential intolerance or allergy, talk with their pediatrician about a plan for selecting the best infant formula for your baby.
- Continue to feed infant formula until 12 months of age. No Goldilocks mixing with cow’s milk or other milk-substitutes prior to that 1st birthday.
Here’s some physician-reviewed information on infant formulas from the NIH:
Standard milk-based formulas:
• Almost all babies and infants do well on these formulas. Fussiness and colic are common problems. Most of the time, cow’s milk formulas are not the cause of these symptoms and parents do not need to switch to a different formula.
• These formulas are made with cow’s milk protein that has been changed to be more like breast milk. Lactose and minerals from the cow’s milk, as well as vegetable oils, minerals, and vitamins are also in the formula.
Soy-based formulas:
• These formulas are made using soy proteins. They do not contain lactose. The American Academy of Pediatrics recommends soy formulas for parents who do not want their child to eat animal protein, and for infants with galactosemia or congenital lactase deficiency.
• Soy-based formulas have not been proven to help with milk allergies or colic. Babies who are allergic to cows’ milk may also be allergic to soy milk.
Hypoallergenic formulas (protein hydrolysate formulas):
• This type of formula may be helpful for infants who have true allergies to milk protein, and for those with skin rashes or wheezing caused by allergies.
• Hypoallergenic formulas are generally much more expensive than regular formulas.
BookMama says
It’s interesting how different babies react to the same formulas. My oldest was exclusively formula fed from six weeks on, and I just bought whatever was on sale/I had a coupon for/store brand. He tolerated it all well. My middle child was mostly breastfed but got formula once in a while. We quickly found out that Enfamil and Similac made her projectile vomit, but Good Start was perfect for her. (My youngest was completely breastfed and would *never* take a bottle, so no formula for her.)
Wendy Sue Swanson, MD, MBE says
I completely agree! Individuals are individuals. Good thing is it’s okay to wander the aisle and try a new formula if something is not working as you’d hope and/or expect.
Katie says
Could you direct me to the references you used to support your claim that water to reconstitute PIF does not have to be boiled.
Also, even the formula companies accept that formula fed babies have more gastrointestinal disturbances then breastfed babies. Can you direct me to the references you used to support your claim that cow’s milk formulas don’t cause fussiness or colic.
Wendy Sue Swanson, MD, MBE says
Hi Katie,
I’m in the US, so was not referencing for worldwide water sources (it appears you’re in Australia from your address). If you have any concerns about your water source, I would recommend you bring water to a boil quickly (1-2 minute rapid boil, then let cool). Never boil formula itself and don’t boil water for prolonged periods.
here’s a Mayo Clinic link that discusses using tap water:
https://www.mayoclinic.com/health/infant-formula/my00193/nsectiongroup=2
The AAP has no formal stance on this.
Also,
Here’s the link (embedded in the blog post) about fussiness/colic reviewed by 2 clinicians I trust:
https://www.nlm.nih.gov/medlineplus/ency/article/002447.htm
Katie says
Thank you for your reply to my questions. I would be interested in your thoughts on the new WHO recommendations regarding safe PIF preparation. The guidelines you quote seem very cavalier in regard to the safety of your water supplies and the possible bacterial contamination of powdered formula.
Bonnie Kebic says
I’ve never understood the information regarding possible bacterial contamination of the formula itself. Since all formulas direct you to cool formula to room temperature before mixing, boiling the water will NOT kill off bacteria in the formula (since it’s not added while hot). Therefore, the only reason to boil water is to remove possible contaminants from the water itself. Depending on where you live, the water could be reliably safe straight from the tap.
Helmy says
My doc recomended symilac alimentum or gerber so I choose gerber and he was doing ok but then he go back to his pain and gas so we swicht to gerber soother then after 2 oz he want it to drunk but everytime that he was doing it he had a pain so I decided to givi him alimentum but tase awful and smell so I decide to mix both formula I ask my doc and he said it is ok then I see ur comment and u feel more relax jow
Heidi says
I love this article. I save up on samples and coupons and formula checks to feed my little one. Brand doesn’t matter to me they have guidelines to follow or they wouldn’t be on the market and mixing half and half is fine to I try to tell new mommies this and they comment on the babies young digestive track I tell them it’s fine their is the same type of formula in each brand buy what’s on sale don’t freak out and my son also gets breast milk so he is getting the best of both worlds!
Marie says
Question? My son has been on the same formula for 6 months, well i have 4 cans of a different brand just sitting here, is it kk if i give it ti him?
Johanna says
My baby is breastfed and formula as well, at his two months we have him similar advance and it work fantastic but because he was a premee the pediatrician want him on enfamil for premature babies but it was a complete nightmare, poor kid was in pain, gas and very hard time pooping. So doc decide give him enfamil alimentum because he thinks he have an alergie or so, but I’m sure he doesn’t since he did so good first with similar, it did not make sense to me. I gave him enfamil premium and guess what, he was fine for over 3 week but now he is back to his pain and gas, so I was thinking if I could mix half of enfamil infant premium and half of enfamil gentlease? What do you think?
Andewq says
my son is about 1 year old… this works?
Alicia Wilkinson says
I would like to try the formula please my baby is sensitive to certain formula so this might be good for him.
Liberty Wojcik says
Would it be okay to mix half Baby’s only organic lactorelief with similac advance?
Wendy Sue Swanson, MD, MBE says
Hi,
I don’t know of any data that shows there is any issue to make a bottle with 1/2 one formula and 1/2 of another. My question: why do you want to do this, or what is the goal?
Amber says
Hi!
I was just researching something and came across alarming research regarding soy based infant formula. I’m alarmed because it was first recommended to me by my pediatrician and even given to me in the hospital to supplement breast-feeding if I so chose. My first son,age 16 was supplemented with soy formula starting around six months of age. Since that was what we were used and pediatrician ok’d it, I gave it to my daughter who is now 13. My 11-year-old also had it for a few months. But I am now freaking out as I had no idea the dangers that soy formula can pose on a child!!! My son has not had any of the symptoms yet and went through puberty normally. My daughter is developing normally and compared to other girls her age she is no where close to the early onset puberty issues they mention..has not even started her period yet but it’s coming soon I’m sure. I know there is nothing I can do now but I’m so upset at what I am reading about soy and harmful effects on reproduction, infertility and cancer risks. I’m so upset about this!
Hercules Enberg says
This doesn’t make any sense. The formula is well out of their system, isn’t it? Why would their be long term affects? It’s soy— it’s not toxic or poison…or is that implied somewhere? Perhaps you could include a link to the article that is the source of your concern?
Melissa Lucchesi says
Has anyone given half enfamil gentlease and half Similac sensitive? How’d it go?
Gammy says
Is it safe to mix a bottle of 1/2 Neosure and 1/2 Pro-Advanced from Similar? Baby was 6 weeks early and has slowly been putting on weight. New DR wanted baby to have every other feeding the Neosure, but noticed it made baby fussy and have diarrhea. So, thought what would happen if we tried a mixed bottle… Baby seemed to have settled tummy and diarrhea went from water to more solid….. But some said it could cause a chemical reaction. ??? Anyone heard of this?