Formula vs Breast Milk

Make an Informed Choice

cute baby

The AAP advises that mothers breastfeed their babies for at least 12 months, or longer, depending on whether the mother and her baby are eager.

The decision on breastfeeding vs. formula feeding is a very personal one, whether you decide to breastfeed or not, you should not feel pressured to do either.

This is your baby and your body. Your decision to breastfeed or not breastfeed should be based on your own feelings and your own research. After you've learned the facts about breastfeeding, you can make an informed decision.

Breastmilk Composition

Breastmilk is alive! It also changes from time to time and month to month to adapt to the needs of a growing child. All mammals produce milk for their young, but not all mammal milk composition is the same. For example, A mother seal will produce milk much higher in fat to fit the needs of her young.

Composition of Formula vs. breastmilk and Cow's Milk

Most importantly, breastmilk contains many Immune factors that cow's milk and formula do not. 

Fats (lipids):

About half the calories in breastmilk are fat, including DHA and AA, which are needed for brain development. Formula manufacturers have started adding these fats to their formula via fermented algae and fungus from the soil, but the addition of these have not been monitored or researched for safety. The concern is that the addition of these ingredients to formula may alter growth patterns in infants. 


Protein is high in colostrum and about 1% in mature breast milk. The two types of protein found are namely Whey protein and Casein protein. Whey protein is higher in colostrum and starts to even out later on. Mature milk contains 50% Whey and 50% Casein protein. 

Some babies may have allergies towards cow proteins, and these allergies are triggered through formula, that is made from cow protein! 


The primary carbohydrate (sugar) in breastmilk is Lactose. Lactose is essential for brain development, enhances absorption of calcium and iron and is needed for microflora in a baby’s gut. 

Vitamins and minerals:

Water-soluble vitamins like B, C, and folate, are drawn from Mom's blood supply. Fat-soluble vitamins such as Vitamin A, D, K and E are pulled from a mother's stores. Taking supplements will not affect the vitamins in breastmilk unless a mother is acutely malnourished.

Minerals in breastmilk are absorbed much easier than minerals in formula, because of the lactose that helps for easier digestion; this is why formula contains copious amounts of certain vitamins and minerals. 

Other Formula vs. Breastfeeding Factors:

newborn baby


Breastmilk is much easier for a baby to digest. A portion of breastmilk is half digested in 48 minutes, but it takes 78 minutes to digest the same size portion of formula milk. (that’s a whole 30 minutes extra) A breastfed baby’s tummy does not need to work half as hard to eliminate waste, because there hardly is any. 

Changes of milk composition during a feed:

The milk that a baby receives the first few minutes while breastfeeding is called the watery foremilk. As baby drinks, the milk becomes fattier; this is because the milk at the back of the “milk-producing alveoli cells" is fattier. This milk is called the hindmilk. 

Breastmilk composition, changes during the day:

The longer the periods between breastfeeding sessions, the less fat a mother will have in her milk. If she drains her breasts more often, the milk will have more fat in it. 

Milk changes over a few months:

Colostrum is much higher in protein and minerals and lower in fat and carbs compared to mature milk. Milk changes occur as the baby grows. 

Formula stays the same, all day, every day. 

Breastmilk changes with your baby's needs. 

Interesting research article: Composition of breast milk from mothers of preterm infants.

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Formula vs. Breastfeeding
The Pros and Cons

  • A significant advantage of breastfeeding is that breastmilk fights against infections, reducing the incidences of diarrhea, ear infections, and meningitis.
  • Breastmilk changes in nutrition, fats, and quantities to fit your baby's needs as he/she grows. (as mentioned above)
  • The advantages of breastmilk include protection against asthma, diabetes, obesity, allergies, and SIDS “sudden infant death syndrome."
  • Breastmilk is easier to digest compared to formula, making it the perfect food for a baby’s immature digestive system. This is why breastfed babies have been found to have less constipation and diarrhea than formula fed babies. More information about breastfed baby poop. 
  • Formula vs. breastfeeding cost. Breastmilk is entirely free, while formula becomes more expensive each month. Babies who breastfeed have been found to go to the doctor less often than formula-fed babies, and this then saves mom and dad more money.
  • Babies are introduced to different flavors and tastes of food via the mother's breastmilk, making a child more likely to want to try these foods later in life.
  • Breastmilk is convenient and always available. No warming or washing of bottles.
  • Studies show that formula fed babies have a lower IQ than breastfed ones.
  • The skin-on-skin contact between a mother and her baby during breastfeeding helps enhance bonding.
  • Breastfeeding can help a mother lose her postpartum weight much faster.
  • Breastfeeding can prevent all sorts of diseases and even cancer in mothers, later in life.

Breastfeeding Challenges

  • Some mothers do not feel comfortable enough to breastfeed in public. 
  • Breastfeeding can get really challenging at times, especially when starting out. A few common issues include engorgement, sore nipples, and even thrush or mastitis. A mother will need ample patience and perseverance, although some mothers find it as easy as pie. It all depends on personal circumstances. Moms may feel inadequate and may give up on breastfeeding, due to a lack of knowledge. 
  • Breastfeeding can become tiring. A baby is entirely dependent on the mother, and this may cause her to feel overwhelmed.
  • Mothers who are on strong medications may need to monitor their babies. 

Formula Feeding Advantages 

  • Other family members get a chance to feed the baby (although this is also possible if mom is breastfeeding and pumping her breastmilk).
  • Another one of the benefits of bottle feeding is that the mother does not need to worry about breastfeeding in public.
  • Formula digests slower than breastmilk, and therefore it keeps a baby fuller for more extended periods of time; sometimes giving them a more extended stretch of sleep at night too.
  • It is easy to monitor the amount that a baby is drinking.
  • More flexibility and freedom for a mother to leave her baby with others. 
  • No interference with lovemaking or fertility.

Disadvantages of Formula Feeding

  • It is expensive, especially if the baby has special needs (soy or hypoallergenic formulas).
  • It requires a lot of preparation and cleaning afterward.
  • Formula contains no antibodies, meaning that it cannot protect the baby against infection, allergies, and illness.
  • Formula fed babies are more likely to show colic symptoms and constipation due to the formula being difficult to digest.

Whatever you decide, you should not feel guilty about your decision. It’s better for your baby to have a happy formula feeding mommy than a grumpy mom who breastfeeds and vice versa.

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Why Breastfeed?

Even though it is natural, it does not always come naturally, because breastfeeding is a skill you have to learn. And it's a learning process with each of your babies. Just because you successfully (or unsuccessfully) breastfed one child doesn't mean the same will be true for your other children.

Breastfeeding is a high touch activity. It provides your baby not only with nutrition and nourishment but also with shelter, love, and security. It's one way of meeting your baby's touch needs that ultimately helps them to thrive and grow into a strong and healthy person.

The WHO (World Health Organization) estimates that up to 220 000 children's lives could be saved every year if all babies were breastfed.

The Benefits of Breastfeeding

Both the mother and her baby will benefit from breastfeeding. It is not just about the nourishment that breastmilk provides, it's also about the nurturing and the comfort it provides.

Bonding, Attachment, and Trust.

When you nurse your baby, it's the act of holding your baby, making eye contact, stroking your baby and physically being close to each other, this promotes bonding.

You wire your baby's brain to feel safe, secure and loved. Later in life, breastfed babies are able to handle stress better, because they had this secure start in life and learned that their needs will be met.

Soothes Pain and Discomfort.

The sucking movement alone can soothe and relieve pain. All babies are born with an instinctual need to suck. Add to this the skin to skin contact that breastfeeding provides and you have a winning recipe for relieving pain and promoting the healing process. You are also able to keep an eye on your baby, to quickly recognize any problems that might need to be addressed.

sleeping baby

Promotes Sleep.

Breastfed babies need to work a little harder to get their milk than bottle-fed babies do. The sucking can really tire them out. Combine this with a full tummy, the warmth and comfort of a mommy's arms and you have an easy way to help your baby to fall blissfully asleep!

It is sad that some experts advise parents against providing this comfort to babies. They tell us to "train" your baby to fall asleep on their own. But nursing to sleep is nothing more than an inborn, natural instinct. 

When we "train" our babies to do something contrary to their instinct, what actually happens is that their brains are flooded with stress hormones, and the baby eventually does fall asleep, but out of pure exhaustion. And to make matters worse, you as the parent are also flooded with stress hormones from hearing your baby cry that much, and you have a hard time going to sleep too.

Breastfeeding promotes peaceful, quality sleep for both the baby and the mother. 

Better Mouth and Teeth Formation = Better Speech Development.

A baby's jaw and facial muscles are strengthened through breastfeeding. When a baby drinks from a bottle, their mouth is shaped according to the teat of the bottle. When breastfeeding, the mother's nipple will change its shape to fit the baby's mouth.

Not only does this produce teeth that are better aligned, but it also benefits the baby's speech.

Visual Development.

The distance between the crook of your arm where your baby lies to nurse and your face is the exact distance a newborn baby sees at best. When baby watches your facial expressions and sees the love beaming off your face, it not only makes them feel nurtured, but it stimulates their vision as well.

Nourishment and gut protection.

Did you know that breastmilk contains white blood cells, which protect your baby against infections and illness?

Learn more about how breastmilk protects your baby's gut. 

Comfort and Confidence.

Mothers and babies don't stop needing each other when the pregnancy is over. Your body continues to be the primary source of everything they need: nutrition, safety, and love.

Breastfeeding is an easy way to provide all of these and in return boosts your confidence. You have a great parenting tool, which you can use at any time, for any need.

As a little bonus, you get the feeling of accomplishment when you watch your baby grow and thrive... on your milk alone, in those early weeks and months. Believe me, there are a few other things that can match that.

You are forced to rest.

This was one of my favorite benefits of breastfeeding. It forced me to sit down and rest often every single day.

Sure, you will learn to feed your baby while on the move, or while wearing them in a carrier, but for the most part, you are guaranteed periods of rest, as you sit or lie down with your baby for feeds. You can breathe and enjoy the moment.

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Combination Feeding

Feeding your baby formula and breastmilk together is not recommended under normal circumstances. If you breastfeed exclusively, it is the best thing you can do for your baby.

Unfortunately, there are a few times when a baby has to be supplemented with formula. In some cases, feeding the baby a combination of breastmilk and formula is necessary. 

Always remember though that breastmilk is the number one choice, then the second best is donor breastmilk and lastly formula!

Ultimately, it is your choice what you do, but here are the facts…

Disadvantages of Supplementing with Formula

  • An artificial nipple may cause nipple confusion, suck problems and refusal of the breast. This usually occurs, if a baby is younger than 6 weeks and an artificial nipple is introduced.
  • Supplementing will decrease milk supply. A baby might not drink from the mother as much, and therefore her supply will decrease. 
  • Supplementing breastmilk may lead to the breasts becoming engorged and painful. 
  • Most mothers who supplement, end up breastfeeding for only a short period of time.
  • To supplement breastmilk with formula will not help combat Jaundice, but will make it worse. Breastmilk acts like a natural laxative to eliminate meconium, and this helps in lowering bilirubin levels. A mother should only supplement if she does not have enough milk.
  • Babies cannot be treated for Hypoglycemia by supplementing breastmilk with formula.
  • Formula contains cow protein, which can increase the risk of allergies. Breastmilk protects a baby's gut and digestive tract. 
  • Formula increases the risk of diabetes in infants who are already at higher risk. 
  • Formula can change the flora of a baby’s gut. 
  • Formula supplements can also cause weight loss.

Water Supplementation

  • Extra water is not needed. Breastmilk is over 80% water and contains all the water a newborn needs. A breastfed baby (even in the hottest climates) does not require additional water.
  • Water is sometimes given to lower bilirubin (babies with Jaundice), but this just makes the Jaundice worse. 
  • Water supplements do not prevent dehydration, and they may even cause weight loss. 

When is Breastmilk Supplementation with Formula Needed?

  • A breastmilk supplement (preferably breastmilk) can be given to babies who are too weak to suck at the breast.
  • A supplement with formula may be given to babies who have severe oral abnormalities. Babies who suffer from cleft lip/palate abnormalities are not always wholly unable to breastfeed.
  • Babies who are separated from the mother because of illness. 
  • Low birth weight babies. In this case, it would be even more important that a baby gets donor breastmilk instead of just formula.
  • Very premature babies who are born before 32 weeks. (Also always consider donor milk first).
  • When there is not sufficient breastmilk produced. Supplementing due to low supply.
  • Dehydrated or malnourished infants. 
  • The death of the mother means that a baby will need to be either completely formula fed or given donor supplement breastmilk.

When Supplementation is Needed Temporarily

  • The mother has taken a medication that could be dangerous for her baby such as antimetabolites, radioactive iodine, or some anti-thyroid medications. So in other words, during the time that the mother has these drugs in her system, she should supplement with formula or donor breastmilk (if available).
  • The mother is using street drugs such as heroin or cocaine. While a mom has street drugs in her system, the baby will need to drink formula or donor breastmilk only.
  • The mother has the Human T-cell Leukemia Virus.
  • The mother has Varicella zoster (a virus similar to chicken pox) During the infection she can give her baby formula and then continue to breastfeed afterward.
  • The mother has herpes simplex virus on her breasts. Once the sores have healed, breastfeeding is safe.

Babies who Cannot Drink Breastmilk

  • A baby with Galactosemia. This is a rare condition in which a baby cannot digest galactose in milk.
  • Babies with PKU who cannot tolerate phenylalanine. 
  • The mother is HIV positive. In some cases, mothers with HIV are advised not to breastfeed at all but, in the lower standard of living circumstances, it is sometimes best if a mother continues to breastfeed. 

When it is Not Necessary to Stop Breastfeeding

  • Some conditions in which breastfeeding should continue are Hepatitis B, Tuberculosis, Lyme disease, and Mastitis.

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Is it Safe to Physically Mix Breastmilk and Formula?

It is not recommended to put formula and breastmilk in the same container. Why? Formula spoils much quicker than breastmilk. Formula bottles should be discarded after an hour, whereas breastmilk can be kept much longer, without being spoilt. This is to prevent the wastage of precious breastmilk.

The best is first to feed your baby the breastmilk and then feed him/her the formula; this way you know that none of your breastmilk had gone wasted.

Do not ever mix formula with breastmilk, instead of water! The concentration will be too intense for your baby’s kidneys and your breastmilk's composition will be changed.

Safe breast milk storage guidelines. 

What if Baby is Refusing to Drink from a Bottle?

  • Sometimes, it is best to get someone else to offer the bottle to your baby. This is so that he/she does not expect to be breastfed.
  • Try to give him/her the bottle at night, in the dark.
  • Try different brands of teats, until your baby finds one that he/she prefers. Avent baby bottles have been found by many moms, to be the best of the natural baby bottles and nipples. Use alternative feeding methods instead of artificial nipples, if possible. 
  • If you are decreasing your breastfeeding times and want to start introducing formula, it should be done gradually, this will ensure that your body has the chance to adapt and will give your baby's tummy a chance to adjust. Mothers that add mixed feedings abruptly may develop mastitis, and their babies may develop some digestive issues.