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Ultimate Formula Feeding Guide

This collection of information was taken from a series of social media posts on @milkbud.lactation.prenatal from February 2021

Formula is reliable and safe for times when breastfeeding is not going well and support is not feasible or attainable.  Formula is also safe

Formula has saved the lives of millions of babies.

But, formula companies have used MANY sneaky and unethical marketing tactics to convince mothers that their milk will never be sufficient. They have made parents think that problems exist when they don’t and they rely on their ability to make parents feel inadequate and doubt their abilities. How many parents out there have bought formula “just in case?”. Those purchases alone have put billions of dollars into the pockets of corporations.

As much as I despise large corporations who prey on parents’ insecurities, I also FULLY SUPPORT your choice to formula feed! If this is your chosen method of infant feeding, you deserve experts who are supportive and can provide appropriate, evidence-based education.

As an infant feeding expert, I recognize my need to keep “abreast” (LOL) of all current data, products, and methods relevant to formula-feeding families.

I am going to share with you what I have learned:
– How to choose a formula?
– How do you prepare and store it?
– How is it made?
– How much to give?
– Bottle feeding techniques


Corporate Manipulation

If formula feeding is your choice, I want it to be just that: YOUR CHOICE.  Not because the copious marketing efforts of the (mostly) large corporations who manufacture and sell baby formula have programmed us to doubt our bodies.  ⁠

⁠I definitely do not want this to turn into a preachy pro-breastfeeding rant.  That wouldn’t be genuine because I’m actually NOT pro-breastfeeding; I am totally pro-woman (and a little bit anti-corporation).

I have always felt like successful breastfeeding sends a huge F-U to these massive companies.

Hear me out.⁠

⁠One prime example of this is the bottles of ready-made formula available in most hospitals.  These bottles only come in the 60ml (2oz) size.  Now, if you give this to even a newborn baby, more often than not, they will GUZZLE IT DOWN!  ⁠

⁠When you give families a visual of this 2oz bottles of formula compared to the scant drops (I mean DROPS) of colostrum expressed in the first day of life and it is NO WONDER that moms think they are not producing enough.  ⁠

Some babies need the extra volume and calories that formula provides. Healthy, term newborns do not need that amount.

Your baby’s cluster feeding does not mean that you can’t produce enough milk- it is nature’s way of getting your body to produce what they will need! ⁠

This is just one example but these subtle visuals and messages are what formula companies prey upon.  They want you to buy their product.  The problem is that this isn’t informed consent; it is marketing, mind games, and trickery (and let’s be honest, the lack of solid information out there about breastfeeding also prevents informed consent when it comes to infant feeding).  ⁠



How confusing is it to walk into the store and see floor-to-ceiling displays of baby formula?

The truth is, there are very few differences in nutrient and caloric profile when looking at brand alone.

Health Canada has strict regulations on infant formula, thus, they are very similar. Comparing a hypoallergenic formula of one brand vs. another, you will see very few differences. The same goes for comparing a basic or “gentle” formula between brands. The rest is just marketing.

Unfortunately, it can take some trial and error in choosing an infant formula. If your baby was born full-term, and is healthy- start with the basic formula of any brand and see how they respond.

If you notice your baby is extra fussy, appears to be uncomfortable, is struggling to pass gas or poops, then you may want to look at switching to a partially hydrolyzed (“gentle”) version of the formula.

If you are still sensing that your baby is not tolerating it, then you will likely want an assessment by your family doctor or pediatrician before switching formulas yet again.


How can an IBCLC help you with formula feeding?

The truth is, we are here to support moms. We aim to provide evidence-based education and support and help you ACHIEVE YOUR INFANT FEEDING GOALS.
If those goals involve formula feeding, your IBCLC can help! ⁠

Formula feeding is NOT an easy way out.

You probably know this by now, but there are no easy ways out in parenting!⁠

An IBCLC can help you navigate the nearly impossible choices when it comes to formula, bottles, nipples, formula preparation, feeding techniques, managing gas and tummy upset, avoiding over-feeding, and creating bonding additional bonding opportunities! ⁠

You may need to “shop” around for the IBCLC that fits your needs, you definitely do not need someone whose primary aim is to push their agenda. Breastfeeding is borderline miraculous, but it isn’t for everyone. Feeding is only one facet of your baby’s well-being. It is not the be-all end-all of infant development. I, and most other IBCLCs I know, want all parents to feel confident and informed in their infant feeding journey! ⁠

Choosing the Formula

It is so hard to navigate all of the different types and brands of infant formula.  Are they all equal in quality?  No. Are they all great sources of nutrition for you baby? Also no. ⁠

Thus, we have some homework to do! ⁠

First: What are Your Baby’s needs? ⁠

  • Are they having any symptoms such as excessive gas, discomfort, lots of fussiness, reflux, excessive spitting-up?⁠
  • Have they been diagnosed with an allergy to a cow’s milk protein? Soy? Anything else? ⁠

Second: Logistical Concerns⁠

  • Cost⁠
  • Availability (is it at your local store, or do you have to order in online?⁠
  • Other desired ingredients: do you prefer an organic formula? Vegan formula? ⁠

⁠After this, it can sometimes take some trial and error before you find the right formula for your baby! I have seen babies who react poorly to one formula, but then do just fine on another with a very similar ingredient profile.  ⁠

Lastly, check the ingredient list! Here is a short guide of the main things to look for:

Ingredient Guide


The main carbohydrate in breastmilk is LACTOSE.  On ingredient lists, you may see sucrose, maltodextrin, brown rice syrup, or corn syrup solids.  Lactose is the optimal choice, choose one with lactose listed close to the top of the ingredient list.⁠


Breast milk and cow’s milk are a combination of WHEY and CASEIN proteins.  Casein takes longer to digest and provides that feeling of fullness. Whey protein is easier to digest.  You want a balance of these proteins that makes your baby feel full but with easy to digest proteins for their brand new digestive systems.  Breast milk protein amounts change but it is usually 60% whey and 40% casein.  Cow’s milk is 20% whey and 80% casein.  Basically, you want to look for WHEY PROTEIN close to the top of the ingredient list. ⁠

Vegan formulas will have a SOY PROTEIN ISOLATE.  ⁠


Several oils are used to provide fats in infant formula. Fats are necessary for neurological development.  You will see several listed that include vegetable oil, sunflower oil, or soy oil.  Any of these are good options.  You may also see DHA or AHA- these are essential fatty acids- fabulous for brain growth.  These are usually produced from algae sources.⁠

⁠Other great ingredients for overall gut development and health include things like GALACTO-OLIGOSACCHARIDES (which is a pre-biotic)as well as LACTOBACILLUS and/or BIFIDBACTERIUM (probiotics)⁠

A Guide to Proteins

In my earlier post, I discussed basic differences between Whey protein and Casein protein in both breast and cow’s milk. ⁠
However, there are a few other terms that refer to the proteins found in baby formula that you should be familiar with.⁠

Partially Hydrolyzed:⁠

The proteins (both whey and casein) are partly broken down into smaller, more easily digestible particles. You will often see the word “gentle” on the label. ⁠
These formulas can be helpful for babies with any digestive discomfort, or skin conditions such as eczema. They are not suitable for babies with an allergy to cow’s milk protein. ⁠


The proteins are nearly fully broken down, making the particles even smaller. These formulas are often effective in managing allergies to cow’s milk proteins, as the particles are so small that they are very unlikely to cause an allergic response. But yes, there are still partial milk ingredients in these formulas. ⁠

Elemental/ Amino Acid based:⁠

These are for babies with severe milk protein allergies, and allergies to other compounds, such as soy. These formulas are completely hypoallergenic, do not contain any milk products at all. They are made up of amino acids, which are the smallest building blocks of protein. ⁠

Soy protein isolate:

These formulas are for parents wanting a vegan formula, for lifestyle or religious reasons. They are also great options for infants with cow’s milk protein allergies, as they do not contain any milk products. Soy formulas are also often lactose free, making them great choices for babies with metabolic disorders that prevent them from processing lactose.⁠ Keep in mind that soy protein is made up of larger particles, and may take more work to digest.⁠

More about Soy

Most infant formula is made from dairy (cow’s milk) sources.  There are a few reasons that people would want to avoid dairy.

For parents wanting to avoid dairy or cow’s milk protein, the infant formula options are: hydrolyzed formulas, hypoallergenic (amino acid) formulas (which I discussed in an earlier post), goat’s milk (which I haven’t discussed yet), or soy.

Why choose soy?

– Religious reasons

– Ethical reasons (vegan diet)

– Babies with a Cow’s Milk Protein allergy

– Babies with Hereditary Lactase Deficiency or Galactosemia (metabolic conditions that prevent babies from breaking down the sugars in both cow and human milk- as lactose is the primary sugar present in both).  In these cases, the soy-based formula must also be lactose-free (which most are).

What the evidence says:

Other than the above conditions, there are really no other indications or benefits to substituting a cow’s milk formula with a soy-based one.  Infant formula is heavily regulated, and all infant formulas have very similar nutrient profiles.

Across the board, current research says that: soy formulas contain sufficient nutrients and calories to support a healthy baby’s growth and development needs.

I read several different peer-reviewed articles from 2014-2021, along with information from Health Canada, and they all stated that more research is definitely needed to fully assess long-term effects of soy-based formula on growth and development.

Soy-Based Infant Formula: What are the common beliefs and concerns?  Are they valid? Like almost everything else: MORE RESEARCH IS NEEDED.⁠

In short: Human studies haven’t observed any significant long-term effects of soy formula.  There has been little to no difference in sexual development or brain, thyroid, and immune function.⁠

Soy has been positioned in the market as being a “healthier” option, with many believing that it reduces colic, allergies, and risk of disease later in life. This is not proven in current data- there is not enough evidence to make any of these claims.  Soy can also be an allergen, so any company making a claim that soy is hypoallergenic must be carefully assessed by you as the consumer. Much more research is definitely needed.⁠

Alternatively, soy has also been villainized in the market due to isoflavones, aluminum content, and GMOs.⁠


Compounds that mimic the effects of estrogen in the body, are thought to disrupt sexual development.  A few older studies suggested that girls fed soy formula as babies may experience longer, heavier, more painful periods and have a higher risk of endometriosis.  HOWEVER, other studies debunked this somewhat in that the onset of menstruation was an average of  5 months earlier, and the length of periods were an average of only 9 hours longer. There was also limited data linking soy to endometriosis later in life. ⁠


in soy-based formulas are higher than those in cow’s milk formula, though data shows that these levels are low enough to be safe for healthy infants with healthy functioning kidneys.  Aluminum may impair calcium absorption; thus, modern soy formulas contain higher calcium levels.  More research is needed to study effects in preterm and low birth weight infants, thus soy is not recommended for these babies.⁠

“GMO-Free” is also a catchy marketing tool.  Soy crops are commonly genetically modified, but more research is needed to fully demonstrate the long-term effects.  GMO-free soy formulas are available on the market, if this is a concern to you.⁠


Formula Preparation

Powdered Formula is a great option for healthy babies born at full term as it has a much longer shelf life than prepared formula.⁠

You must prepare the formula according to the directions on the package, as you must provide optimal ratios of formula and water.⁠

General steps for powdered formula preparation are outlined by Health Canada and the World Health Organization:⁠

Prepare your space:⁠

Clean your countertops and hands with soap and warm water before beginning.⁠

Sterilize bottles, nipples and spoons by boiling in an open pan of water for two minutes. Allow them to air dry and cool. Cover them with a clean tea towel if you’re not going to use them right away.⁠

Prepare the formula:⁠

  • Boil tap water for two minutes.⁠
  • Cool the water to 70°C, add the powder and mix thoroughly.⁠
  • Allow the formula cool again before serving it to your baby.⁠
  • Serve formula as soon as possible after it has been prepared, but always check the temperature of the formula on the inside of your wrist before serving it to your baby to make sure it isn’t too hot.⁠
  • Boiled water that has cooled to room temperature can be used as long you serve the formula to your baby right away.⁠

Babies born prematurely, at low birth weight, or with vulnerable immune systems should be fed commercially prepared, ready-to-eat liquid infant formula and not powdered formula. Powdered formula does have a higher risk of contamination by a bacteria called cronobacter sakazakii, which thrives in dry goods such as formula, teas, flour, etc.  It can cause serious illness in infants.⁠


How is Infant Formula Made?

During my time as an IBCLC, I have read infant formula-related articles and opinion pieces from many different points of view.  The extremes of information are staggering: some state that there are no differences between breast milk and formula, while others compare it in quality to feeding your baby Dino Nuggets.  ⁠

The reality is, infant formula falls somewhere in between.

Formula is a safe and nutritious option for infant feeding. While yes, it is a processed food, I definitely wouldn’t compare it to Dino Nuggets.

Infant formula goes through rigorous testing and quality control (especially in Canada).  ⁠


This is when it is heated to a specific temperature, then cooled to ensure that no harmful bacteria can remain.⁠


During this process, fat and oil particles are broken down to ensure that separation doesn’t occur during the product’s shelf life. ⁠


This occurs when specific product attributes such as pH, fat content, nutrients, etc. are tested.⁠


This kills any bacteria that remain.  The formula is then sealed in sterile containers, which are then heated under pressure to render the product commercially stable. (Powered formula undergoes a process through a “spray dryer”, in which product is sprayed into heated air.  The moisture leaves upward with the air and the dry product remains to be sterilely packaged. ⁠

SAFETY NOTE: dented or damaged containers of infant formula (powered or prepared) should not be purchased.  Damage to the outside of the package can compromise the seal and allow bacteria to enter and grow.  ⁠


How Much & How Often?

The tummy of a newborn is tiny!  They definitely do not need a full bottle of formula at each feed during those first days!.

If you are exclusively formula feeding, I recommend offering 0.5-1oz of formula every 2 hours or so (as a general guideline).

Beware of the feeding “schedule”:

Like I tell breastfeeding moms- watch the baby, not the clock!  Your baby will tell you when they are hungry! If your baby is still showing signs of hunger after they take in your offering, then given them more, in increments of 0.5oz in those early days.  Their tummy grows pretty rapidly within that first week of life, so you will be able to increase amounts to 2-3oz per feed.


As your baby is able to take in more formula per feed, the interval between feedings may also get longer.  Again, watch the baby, not the clock!  Most infant formula-fed newborns will feed 8 to 12 times in 24 hours.


Some feeding sessions may be long, and other feedings short. That is okay. Babies will generally take what they need at each feeding and stop eating when they are full.


Bottle Feeding Technique

Paced Bottle Feeding

This technique slows down the feeding process but decreases overfeeding  and air entry into the tummy (aka: prevents GAS!).

Don’t overthink this technique!

All you need to do is:

  • hold your baby in a mostly upright (sitting) position
  • hold the bottle nearly horizontal
  • make sure the nipple is filled with formula
  • allow your baby to suck a few times, then slowly pull the bottle away, allow them to take a few breaths, offer the bottle again, and keep repeating the process until the feed is complete.


This technique is in contract to traditional bottle feeding, wherein we hold the baby laying down and tip the bottle downwards into their mouth.  The fast flow of formula actually can cause larger amounts of air intake.  It is also very easy to overfeed babies using this method because they will guzzle down every drop pouring down their throat!

So many bottles and nipples to choose from. How do you choose? ⁠

I am not sponsored or paid by any brands, though I am not above it- I would welcome any money they want to give!⁠

However, the choices are overwhelming and I want you to be market savvy when it comes to these products.  Nearly every item will promise that its look and feel is “most similar to the breast”.  Um, whose breasts and nipple look and feel like any of these things?  I’m a lactation consultant and I’ve seen thousands of breasts and none are the exact same so how can these companies make this claim? There just aren’t enough eye rolls for this!⁠

There is often a period of trial and error to find what works best for you and your baby

You can start by looking for the following qualities:⁠

  • Slow Flow nipple (always, for all healthy term babies)⁠
  • A nipple that gradually tapers: wider at the base, with a gradual change to the narrower end)⁠
  • Something that is comfortable for you to hold in size and shape⁠
  • Vented or angle-neck bottles promise to decrease air intake.  However, these are not proven to do this.  Extra vented pieces also mean more cleaning will be involved!⁠
  • All baby bottles are BPA-free plastic, and are safe, but many parents are starting to opt towards glass.  ⁠
  • Consider other logistical factors in your choice such as cost, availability, ease of cleaning, etc.⁠


Caregiver feeding instructions

When you are leaving your baby with a caregiver, it can be stressful: how will they know when to feed the baby?  How much are they going to feed? What if they don’t feed enough?⁠

If you are exclusively formula feeding, you probably have a good idea of how much your baby requires and when.  I suggest providing caregivers with fool-proof instructions.  You can prepare and pre-fill and label bottles (“lunchtime feed”, “bedtime feed”, etc.  This makes it easier for everyone so there is no guesswork involved and you can focus during your work day, or enjoy an evening out, without worrying (haha, JK, you’re still gonna worry!) ⁠

If you are breast AND formula feeding, you may need to be a bit more strategic.

For example, if you are back at work and are picking your baby up at 5pm, you may want to instruct them not to give your baby a bottle after 3:30pm.  Then, they will be hungry and you can breastfeed when you pick them up.  A lot of moms returning to work find that their babies are fed so much during the day that they have little to no interest in breastfeeding in the evening.   To preserve those evening breastfeeds, definitely give clear feeding instructions to your baby’s caregiver, as well as tips on how to soothe your baby that don’t involve overfeeding (many caregivers, friends, family members, and GRANDMAS tend to treat all crying episodes with more bottles).⁠

It definitely takes some planning, some strategy, and priority-setting to find the right feeding plan for your circumstances!  Don’t hesitate to reach out for tips and advice!⁠

Formula Poops

Breastfed babies’ poops are typically yellowish, seedy, fairly runny, and, according to Bling Empire on Netflix, smell like popcorn (and I agree). ⁠

The poops of formula-fed babies are different. They are usually more brown in color and have a thicker consistency, kinda like peanut butter…..but it definitely doesn’t smell like popcorn. Or peanut butter for that matter.  It smells pretty bad, to be honest. ⁠

Formula-fed babies do tend to have less frequent bowel movements.

3-4 poops per day is common (compared to over double that for breastfed babies).  ⁠

When feeding a combination of breastmilk and formula, your baby will have a mixture of these kinds of poo.⁠

If your formula-fed baby is not stooling 3 times per day, if their stools are thicker or firmer than normal, and/or if your baby seems like they are struggling to pass stool, it could be a sign of constipation and you should consult your pediatrician or family doctor. Additionally, if your baby is younger than 6 months and you are concerned about constipation,

Don’t feed them anything other than formula or breastmilk until you consult with your care provider.


You could consider switching to a partially hydrolyzed formula to see if the partially broken down proteins help your baby to more easily digest.  However, beware of switching formulas too often, as that can also disturb their tummies.⁠



Whew!  And that’s it! My month-long series on formula feeding all in one place!
Some great resources for you include:

The Canadian Paediatric Society has this site with links to handy, easy-to-read parent handouts on a variety of topics:

Health Canada’s page on infant feeding is less “reading friendly” but is very informational. Scroll down to just past halfway through the document and you will find some great information on infant formula!



Adgent, M. A., Umbach, D. M., Zemel, B. S., Kelly, A., Schall, J. I., Ford, E. G., James, K., Darge, K., Botelho, J. C., Vesper, H. W., Chandler, D. W., Nakamoto, J. M., Rogan, W. J., & Stallings, V. A. (2018). A Longitudinal Study of Estrogen-Responsive Tissues and Hormone Concentrations in Infants Fed Soy Formula. The Journal of clinical endocrinology and metabolism103(5), 1899–1909.

American Academy of Pediatrics. (2008). Effects of early nutritional interventions on the development of atopic disease in infants and children: The role of maternal dietary restriction, breastfeeding, timing of introduction of complementary foods, and hydrolyzed formulas. Pediatrics, 121; 183-191.

American Academy of Pediatrics Committee on Nutrition. Use of Soy Protein-Based Formulas in Infant Feeding (Policy Statement). Pediatrics. Vol. 121 No. 5 May 2008, pp. 1062-1068.

Critch, Jeffrey N; Canadian Paediatric Society; Nutrition and Gastroenterology Committee, Nutrition and Gastroenterology Committee. Paediatr Child Health 2014;19(10):547-49

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Jefferson WN, Patisaul HB, Williams CJ. Reproductive consequences of developmental phytoestrogen exposure. Reproduction. 2012 Mar;143(3):247-60. doi: 10.1530/REP-11-0369.

Sinai T, Ben-Avraham S, Guelmann-Mizrahi I, Goldberg MR, Naugolni L, Askapa G, Katz Y, Rachmiel M. Consumption of soy-based infant formula is not associated with early onset of puberty. Eur J Nutr. 2019 Mar;58(2):681-687. doi: 10.1007/s00394-018-1668-3. Epub 2018 Mar 20. PMID: 29556760.

Upson K, Adgent MA, Wegienka G, Baird DD. Soy-based infant formula feeding and menstrual pain in a cohort of women aged 23-35 years. Hum Reprod. 2019 Jan 1;34(1):148-154. doi: 10.1093/humrep/dey303. PMID: 30412246; PMCID: PMC6296212

Vandenplas Y, Castrellon PG, Rivas R, Gutiérrez CJ, Garcia LD, Jimenez JE, Anzo A, Hegar B, Alarcon P. Safety of soya-based infant formulas in children. Br J Nutr. 2014 Apr 28;111(8):1340-60. doi: 10.1017/S0007114513003942. Epub 2014 Feb 10. PMID: 24507712.

Verduci, E., Di Profio, E., Cerrato, L., Nuzzi, G., Riva, L., Vizzari, G., D’Auria, E., Giannì, M. L., Zuccotti, G., & Peroni, D. G. (2020). Use of Soy-Based Formulas and Cow’s Milk Allergy: Lights and Shadows. Frontiers in pediatrics8, 591988.