“A little knowledge can be a dangerous thing. This has never been so true as in the ongoing debate about foremilk and hindmilk and their impact on breastfeeding. The misunderstandings around these concepts have caused anxiety, upset, and even led to breastfeeding problems and premature weaning.”
Nancy Mohrbacher, LLL Leader, IBCLC, FILCA Worries About Foremilk and Hindmilk
What determines fat content of breastmilk?
- Fat content of human milk is relatively constant as it is synthesised in the breast.
- Fat content during a feed is determined by the fullness of the breast. Fat content increases gradually as the breast becomes emptier, as fat globules are “forced” out of the breast by successive milk ejections.
- A longer feed interval means lower initial fat content at the start of the next feed, because fat adheres to the alveoli/ducts while milk stands in the breast between feeds. Therefore, the fat level at the start of one feed may not be the same as the fat content at the start of the next. The longer the gap between feeds, the greater the reduction in fat content from the end of one feed to the beginning of the next.
- Length of feed is irrelevant – some babies take a full feed in 4 minutes per side while others take 40 minutes to get the same amount. You can’t tell anything about fat content from the length of the feed, so let the baby determine it.
What is lactose overload?
(Sometimes previously known as “foremilk/hindmilk imbalance”)
- There is no such thing as “foremilk” and “hindmilk” in the sense that they are not different kinds of milk. The terms simply describe the way that fat content of milk increases as the breast is drained. “Foremilk” is defined as the milk available initially when a baby starts feeding, “hindmilk” as the milk that can be expressed at the end of a feed. “Foremilk” is not necessarily “low” in fat, as it it depends on how much time has passed since the previous feed.
- Fat slows down the transit of milk through the baby’s gut. If a baby takes a lot of milk that is relatively low in fat, it can rush through the gut faster than the milk sugar (lactose) can be digested. This leads to fermentation in the gut.
How do I tell if a baby has lactose overload?
- The symptoms are very specific: GREEN, FROTHY, EXPLOSIVE stools, FLATULENCE (passing wind) and significant PAIN (a lot of screaming, not just occasional complaining). A comfortable baby with yellow stools does NOT have a problem with milk fat content!
- There are several other reasons why a baby might have a green stool, including insufficient total milk intake, illness, medication/supplements and allergy. A green stool ALONE (without flatulence/pain) is not indicative of lactose overload. In a thriving, comfortable baby, an occasional green stool can safely be ignored.
What is the remedy for lactose overload?
- All that may be required is to deepen attachment and encourage the baby to feed for as long as they want on each breast.
- Laid-back or side-lying positioning can help a baby to manage a fast milk flow.
- More frequent feeds can help a baby take in manageable amounts and avoid build-up of large volumes of relatively “lower-fat milk”.
Is it ever appropriate to limit a baby to one breast per feed?
IMPORTANT: Normal feeding etiquette is to let the baby take as much milk as they want from the breast, then offer the next. Most babies will take both breasts, at least some of the time. Deliberately withholding the second breast is a strategy that will REDUCE MILK SUPPLY (by leaving each breast unused for a longer period), limiting a baby to one breast is ONLY appropriate where there is clear evidence that the mother has an OVERSUPPLY of milk:
- The baby is clearly struggling to manage milk flow (gagging, spluttering, coming off the breast when milk ejects) and is distressed by this and/or the baby has the symptoms of lactose overload: GREEN, FROTHY, EXPLOSIVE stools, FLATULENCE and significant PAIN.
- Other measures to help the baby to manage milk flow have been tried but the situation has still not improved.
- AND the baby is growing rapidly (gaining at least 340- 450g/12-16oz per week; growth trajectory crossing centile lines upwards).
Be aware – a compromised baby (premature, unwell, tongue-tied etc.) may not be able to manage a normal milk flow; this baby needs more support, not less milk!
What are the implications for a slow-growing baby?
- A baby whose weight gain is below normal parameters (and has been screened for relevant health conditions) has a problem with inadequate milk VOLUME, NOT fat intake (unless they also have the specific symptoms of lactose overload: GREEN, FROTHY, EXPLOSIVE stools, FLATULENCE and significant PAIN).
- To withhold the second (& third, fourth…) breast from this baby would be to further compromise milk supply and intake.
- Feeding support needs to address EFFECTIVENESS of milk removal (attachment at the breast and/or expression technique), feeding MANAGEMENT (frequency of feeds/expressions) and if necessary, steps taken to increase milk PRODUCTION and provide additional milk for the baby.
- Any baby who is growing unusually slowly should be under the care of a doctor.
Resources for parents
Kelly Bonyata, BS, IBCLC, ‘Fore/hindmilk – what does this mean?’ Kellymom
Kelly Bonyata, IBCLC, ‘What affects the amount of fat or calories in milk?’ Kellymom
Joy Anderson BSc(Nutrition), PostgradDipDiet, APD, IBCLC, ABA Breastfeeding Counsellor ‘Lactose overload in babies’ Australian Breastfeeding Association
LLLGB, ‘The Unhappy Breastfed Baby’
LLLGB, ‘Too much milk & oversupply’
Written by Jayne Joyce for LLLGB, LLL Leader 2017