Forgot Your LLLID? or Create Your LLLID Here
La Leche League International
To Find local support:  Or: Use the Map

Is it OK to mix human milk and artificial baby milk (formula)?

Mixing refers to giving your baby your own milk and artificial baby milk in the same container. This is actually a form of supplementation. Supplementation means giving your baby liquid nourishment in addition to breastfeeding him. Giving your milk and any supplement separately is advantageous for these two reasons:

  • Your baby will receive the immunological benefits of human milk and
  • Less will be wasted than if the milks were mixed.

Reasons supplementation of a breastfed baby may be necessary include if the mother's supply is low or if the baby is separated from mother. However, there are many options in these cases, so be sure to contact your La Leche League Leader.

Mother's supply low

Many mothers who have low supply issues or who are breastfeeding adopted babies choose to do so at the breast with at-breast supplementers. With this method of supplementation, mixing human milk and artificial baby milk does occur. The increased stimulation may improve mother's milk supply while simultaneously providing the innumerable benefits of breastfeeding for baby. This far outweighs any disadvantages of mixing human milk and artificial baby milk.

Baby separated from mother

If you are regularly separated from your baby and cannot pump see our FAQs on Pumping.

Having your care provider offer your pumped milk to your baby separately ensures that all of your "liquid gold" will be used and less will be wasted.


  • Giving artificial baby milk will fill up your baby, making him less interested in breastfeeding. Supplements of artificial baby milk can sensitize some babies to milk allergies or intolerance.
  • Since breast milk production relies on the concept of supply and demand (the more demand made for milk, the more milk the body produces), mothers who supplement could affect the quantity their body produces.
  • Researchers, as well as parents, have noticed that babies may get gassy when receiving artificial baby milk. According to the article "Supplementing the Breastfed Baby" (LEAVEN, August-September 1999):

    "Whenever a non-human milk is used, alterations in the baby's gut flora occur and will cause changes in the frequency, odor, and consistency of baby's stool, as well as affect how the baby settles after a feed (Kleessen et al 1995)."

    This encompasses all types of supplementing situations, such as combining human milk and artificial baby milk or giving human milk at one feeding and artificial baby milk at another.

Human milk is, according to the American Academy of Pediatrics, preferred for all infants. The more human milk they receive, the greater the benefit. Any amount of human milk is a positive addition for your baby.

Resources for Additional Information

Attend a La Leche League meeting in your area for additional information and support. To find a Leader of a local Group, visit Finding a Local LLL Group.

THE WOMANLY ART OF BREASTFEEDING, published by La Leche League International, is the most complete resource available for the breastfeeding mother. It is available from the LLLI Online Store or from your local Leader.

DEFINING YOUR OWN SUCCESS: BREASTFEEDING AFTER BREAST REDUCTION SURGERY, by Diana West: A wealth of information on supplementation, pumping and increasing milk supply. ( Hardcover and Softcover) It is available from the LLLI Online Store or from your local Leader.

Our FAQs present information from La Leche League International on topics of interest to parents of breastfed children. Not all of the information may be pertinent to your family's lifestyle. This information is general in nature and not intended to be advice, medical or otherwise. If you have a serious breastfeeding problem or concern, you are strongly encouraged to talk directly to a La Leche League Leader. Please consult health care professionals on any medical issue, as La Leche League Leaders are not medical practitioners.

Page last edited .

Bookmark and Share