COVID-19 Info | Information sur la COVID-19 | COVID-19 Vaccine Vaccine Receipt | COVID-19 Self-Assessment
🔍 Search
  • Follow us:
Sign In FR

Middlesex-London Health Unit

Inner Nav

Infant Formula

Informed Decision Making about Infant Feeding

Deciding how to feed your baby is one of the many important decisions you will make as a parent. To help make the best choices for you and your baby, you need good, quality information. Middlesex-London Health Unit (MLHU) can help. We support all families regardless of their infant feeding choices. If you have decided to give your baby infant formula, you will need to learn how to safely prepare and feed infant formula to your baby.

Infant Formula Shortage in Canada

There is no current shortage of regular infant formula in Canada. However, there is a shortage of infant formulas for infants with food allergies and certain medical conditions. Please see the latest information about infant formula from Health Canada at


Sterilizing Water and Equipment

Sterilize all formula preparation equipment, bottles and water for babies of all ages for as long as you offer formula to your baby. There is no research that says when it is safe to stop sterilizing.

Always wash your hands and counters before making formula. Tap water and bottled water can be used to make formula. There is no advantage to using bottled water when public water is safe. Do not use carbonated or mineral water to make formula. Distilled water is not necessary.


  • Add water to a pot on the stovetop and let it boil and bubble for 2 minutes to get rid of germs and bacteria
  • Sterilized water can be stored in a sterilized, covered container at room temperature for 24 hours or in the fridge for 2-3 days 


  • Check and throw out any nipples that are swollen, cracked or sticky
  • Wash all equipment that will touch the formula with a brush in hot, soapy water. Rinse well.
  • Sterilize all feeding equipment before each use
  • Place clean bottles, nipples, tongs, knife and can-opener in a pot. Cover the items with cold water and let it boil and bubble for 2 minutes

Telephone Support for Families

Telephone Support for Families


Safely Preparing Infant Formula for Your Baby Video (9:17)

Baby-Friendly Initiative Strategy Ontario (adapted with permission from York Regional Public Health)

Cette vidéo est disponible en français: Préparer en toute sécurité des préparations pour nourrissons

Tip Sheets accompanying this video are available in multiple languages including English, French, Cree, Ojibway, Arabic, Spanish and more.


Infant feeding survey

Infant Feeding Survey
We are interested in understanding the infant feeding practices of young families in our community. Want to participate? Questions? Contact us:

  • Remove items from pot with sterile tongs and allow to air dry on a clean towel.
  • Dishwashers do not reach a high enough temperature and do not sterilize equipment. Microwave sterilizers are safe to use. Be sure to follow the manufacturer’s instructions

Back to the top

Preparing Infant Formula

There are three different forms of formula: 

  1. Powder (mix with water)
  2. Liquid concentrate (mix with water)
  3. Ready-to-feed (no water needed)

Powdered formula is not sterile. Harmful bacteria can be found in powdered formula and can cause food related illness. This is rare and is less of a risk for babies that are healthy and were born full term.

For healthy babies, born full term:

If you are using powdered infant formula for your healthy baby, you can mix the powdered formula with water that has been sterilized and cooled to room temperature. You can mix one bottle at a time and then feed it right away to your baby. Warming the formula is optional.

Babies at greatest risk of infections from powdered formula:

If your baby was born prematurely, had a low birth weight and is under two months of age, or has a weakened immune system, your baby is more likely to get sick from drinking powdered infant formula. It is best to feed these babies liquid infant formula, such as liquid concentrate or ready-to-feed. If powdered formula must be used, it should be prepared in a specific way to lower the risk of your baby getting sick. Check out Health Canada's tips for preparing and handling powdered infant formula to make it as safe as possible for your baby.

Back to the top

Follow the directions on the infant formula packaging:

Using too little water can cause problems for the baby, including:

  • Vomiting
  • Diarrhea
  • Swelling of the intestines
  • Stress on kidneys and digestive system

Using too much water can cause problems for the baby, including:

  • Low nutrient intake, which can prevent baby from growing well
  • Water poisoning, which can make baby very sick and lead to death

Automatic Formula Preparation Machines

Automatic formula preparation machines are not recommended. The water may sit in them too long and bacteria may grow in the water. The water does not reach a high enough temperature to kill bacteria. The machines may also not mix the formula well and may add too much or too little powdered formula or water.

Back to the top

Warming Bottles

  • The safest way to heat a bottle is in a dish of hot water
  • Let the well closed bottle sit in the hot water bath for a few minutes
  • Tip the bottle upside down 10 times then test the formula on the back of your hand
  • It should feel warm, not hot
  • Do not microwave plastic containers, bags and nipples because the plastic could melt and leak into the formula
  • There are health and environmental concerns with using plastic bags and bottles that have been heated
  • Glass bottles can be used, but they still should not be heated in the microwave
  • Check out Health Canada's information about baby bottles and BPA

Back to the top

Formula Safety:

  • Throw away the formula in the bottle: 
    • When your baby is finished drinking from that bottle
    • When the bottle has been out of the fridge for two hours, including heating and feeding time
  • Do not put the unfinished bottle back in the fridge for another feeding.  Bacteria grow faster in formula once it has been taken out of the fridge
  • For convenience and safety during hot weather or while travelling, keep the formula and water separate to prevent the growth of germs, then mix together just before feeding your baby
  • Do not use the formula after the expiry date
  • Know about Infant Formula Recalls and Safety Alerts


When to Feed Your Baby

These cues show that your baby is ready to feed:

  • Baby’s eyes are open wider than usual
  • Baby curls arms and legs up
  • Baby turns toward a touch on the mouth, cheek or chin
  • Baby makes sucking movements
  • Baby tucks hands under chin or sucks on them

Crying is a later sign of hunger. If you wait until your baby cries when he is hungry, he may be too upset and not feed well. 

These cues show that your baby is satisfied and full:

  • Baby falls asleep and is no longer interested in feeding
  • Baby turns head to side
  • Baby stops sucking and lets go of the nipple
  • Baby purses or pinches lips together

Back to the top

How to Bottle Feed

  • Hold your baby in an upright position, so that their head is much higher than their body
  • Place your baby so that you can make eye contact with each other
  • Talk calmly to your baby and smile often
  • Hold the bottle with your hand and do not prop the bottle with a blanket or other item
  • Hold the bottle at an angle so most of the nipple is in your baby's mouth and the nipple is filled with milk
  • Tilt the bottle only a little, keeping it almost flat so that it is easier for your baby to manage the flow of formula
  • Burp baby often (at least 1-2 times per feeding)
  • Do not lay the baby down while drinking a bottle because the formula may slip into your baby’s lungs causing him to choke.
  • Be sure the hole in the nipple is the right size; when you hold the bottle upside down, about one drop per second should come out
  • Watch your baby carefully, they will show you when they are hungry, full or need to burp
  • Feed your baby in different positions so that your baby can look at you from different angles
  • Try switching the hand you hold the bottle with and the arm you hold your baby with
  • Remember that all babies benefit from cuddling skin-to-skin with you

Back to the top

Paced Bottle Feeding: Videos and Information

Back to the top

Recalls and Safety Alerts

Infant formula is a manufactured product. Sometimes things can go wrong while it is produced or packaged. The Government of Canada website lists safety concerns and recall alerts. It is suggested that you write down the lot number of your formula containers to check against recalled lot numbers on this website. Also, ensure that the formula packaging is not broken before using.

Back to the top

Date of creation: February 27, 2013
Last modified on: August 29, 2023


1Canadian Paediatric Society, Dietitians of Canada, and Health Canada (2022-07-26) Nutrition for Healthy Term Infants: Recommendations from Birth to Six Months Health Canada Retrieved from
2Health Canada. (2022-05-20). Preparing and handling powdered infant formula. Retrieved from