Can breast milk cure an eye infection?

eyeOne of the many healing properties attributed to breast milk is the ability to cure eye infections such as ‘pink eye’ — conjunctivitis — or ‘sticky eye’ — a gooey discharge that often accompanies conjunctival inflammation. Conjunctivitis is a common condition that rarely requires treatment, usually clearing up by itself within a week or two. For newborns, however, it can occasionally be quite serious, so ensuring it is properly treated is very important. For everyone else, it can be irritating and unpleasant, so any way of reducing the length of the infection is naturally welcome. Can breast milk really provide any relief?

A study in a hospital in New Delhi, India, examined the effect that routinely applying colostrum to babies’ eyes had on the likelihood of them developing an eye infection1. On one hospital wing, mothers were asked to put a drop of colostrum in their babies’ eyes three times a day; on another wing, mothers were asked not to apply anything. The infection rate was much lower in the babies who received colostrum: only 3 out of 51 babies in this group (6%) developed an infection, compared to 26 out of 72 in the control group (35%).

At first glance, this seems like a convincing result for colostrum, but a closer examination of the figures indicates this isn’t necessarily the case. The normal neonatal eye infection rate recorded at the hospital was just over 5% – roughly the same as the one recorded in the colostrum group. Rather than infection rates going down in the babies who received colostrum, it seems they went up – considerably – in those who didn’t. This may have occurred because the normal practice of wiping eyes with a sterile swab just after birth was abandoned during the study. Fewer babies in the study group may have got infections simply because their eyes were rinsed, not necessarily because it was with colostrum.

There is other evidence that breast milk could help ease the symptoms of conjunctivitis, however: in vitro tests show that colostrum, and to a much lesser extent mature breast milk, can potentially combat some of the bacteria known to cause neonatal eye infections2,3, and another study provides evidence that it does seem to be an effective treatment for eye infections in young babies4. At a hospital in Spain, babies diagnosed with neonatal sticky eye were treated either with antibiotics or breast milk. Babies treated with breast milk generally recovered much faster: 26 out of 45 (57%) of those receiving milk had recovered after 30 days, compared with 3 out of 20 (15%) of those receiving antibiotics. Whilst this does not provide conclusive evidence that breast milk is the optimal treatment for eye infections in newborns, the study’s results were deemed sufficiently encouraging to switch from antibiotic drops to breast milk at the hospital where it took place.

So does this limited evidence that breast milk can treat some neonatal eye infections mean it can be used to treat infections in older children, or even adults? Whether breast milk would have a beneficial effect is not clear: its antibacterial properties mean that it may help to clear up an infection caused by certain types of bacteria, but not necessarily one resulting from an allergy or a virus. Having said this, there is, of course, no harm in trying the breast milk option. If you’re currently nursing, it’s simple and free, and whilst it may not get rid of the symptoms, it almost certainly won’t make them any worse.

  1. J Trop Pediatr. 1982 Feb;28(1):35-7.
  2. J Trop Pediatr. 1996 Dec;42(6):327-9.
  3. J Reprod Immunol. 1998 Jul;38(2):155-67.
  4. J Trop Pediatr. 2007 Feb;53(1):68-9.

The antibacterial properties of breast milk

lab_technicianMany years ago, breast milk was thought to be sterile. While this is far from being the case (it actually contains all manner of germs1), the role it plays in helping keep babies free from harmful disease means it does display some pretty impressive bug-busting capacities.

The immunological components of breast milk help to protect both a mother’s breast and her baby from infection during feeding, as well as aiding the development of the baby’s immune system2. They also have another useful consequence, however: protecting breast milk from disease for some time after it has been expressed, enabling it to be stored. Several studies have examined whether it is safe to keep expressed milk for short periods, and there is general agreement that it can be stored for 8 hours at room temperature (25 degrees C), for three days in the fridge (4 degrees C) and for up to a year in the freezer (-20 degrees C) without any increase in the levels of pathogens (harmful bacteria) it contains3.

Not only does breast milk inhibit the growth of pathogens, however – it actively reduces them. This was convincingly demonstrated in a piece of research examining what happened to milk during short term storage4. Milk was collected from 9 mothers and divided into three samples: the first was analyzed the same day; the second was refrigerated (at 4 to 6 degrees C) for 48 hours; and the third was refrigerated for 72 hours. Each sample was then contaminated with an E.coli solution (the kind of nasty bacteria that dwells in toilets) and left for two hours. When the samples were tested, levels of E.coli had reduced by 80% in both the milk that was fresh and the milk that was 48 hours old. Levels had also diminished in the 3 day-old milk, but only by around 10%, indicating that the antibacterial properties, whilst still present, had started to degrade by this point.

If your baby needs to feed from a bottle or cup, a considerable body of research indicates that it’s safe to give him breast milk that has been stored in the fridge for up to three days, or in the freezer for several months. There is also evidence that if the milk you express does come into contact with germs (keeping pumping equipment sterile in your bag at work isn’t always easy), then the bactericidal components of breast milk should be able to take care of them, providing the milk is under two days old. There may still be potential issues associated with feeding stored, rather than fresh breast milk to your baby: various chemical changes occur in milk once it has left the body, and it’s possible some of these may affect its nutritional value3,5,6. Nevertheless, expressed breast milk remains a healthy alternative to formula, and as a result of its antibacterial qualities, you can rest assured that if your baby can’t feed from you directly, he still has a safe source of food and drink.

  1. Mastitis: causes and management. World Health Organization; 2000.
  2. Adv Food Nutr Res. 2008;54:45-80.
  3. Acta Paediatr Suppl. 1999 Aug;88(430):14-8.
  4. J Pediatr Gastroenterol Nutr. 2007 Aug;45(2):275-7.
  5. Acta Paediatr. 2001 Jul;90(7):813-5.
  6. Biofactors. 2004;20(3):129-37.

Where does fore-milk end and hind-milk begin (and does it actually matter?)

milk-creamAccording to the World Health Organization, breastfeeding provides all the nutrition your baby requires for the first six months of life. This entails satisfying both hunger and thirst, and to meet both these needs you might have heard that your breasts produce two distinct types of milk: thin, watery ‘fore-milk’ to quench thirst; and creamy, calorie-rich ‘hind-milk’ to satisfy hunger.

These apparently different types of breast milk are described in various ways, but a distinction is generally drawn between a watery/creamy consistency, and thirst/hunger. There is also an implication that you need to make sure your baby gets enough hind-milk in order to gain weight. According to

‘Foremilk is the milk which is first drawn during a feeding. It is generally thin and lower in fat content, satisfying the baby’s thirst and liquid needs.
Hindmilk is the milk which follows foremilk during a feeding. It is richer in fat content and is high in calories. The high fat and calorie content of this milk is important for your baby’s health and continuing growth.’ carries a similar description:

‘Foremilk, a bluish-white milk that is lower in fat than the hindmilk is the milk your baby receives in the first part of the feeding.
The hindmilk, which follows the foremilk, is richer and higher in fat than the foremilk. The hindmilk provides most of the nutrients your baby needs to gain weight and grow, and it satisfies his hunger.’

Valorie Delp on goes a step further, and says you can actually see the difference between the two:

‘If you’re really into science, pump a bottle of milk and let it sit out on the counter for awhile. You’ll see the milk separate into two distinctive layers. . .one being much fattier than the other. That’s hind milk and foremilk.’

Valorie’s demonstration is appealing, but it’s unfortunately some way off the mark. The separation she describes is simply the fat in the milk rising to the surface, not a different type of milk. This illustrates quite neatly the problem with using the terms ‘fore’ and ‘hind’: it reinforces the impression that the breast produces two types of milk, when in fact it makes only one. The descriptions shown above aren’t entirely inaccurate – milk does indeed change consistency during a feed – but this happens gradually, rather than suddenly.

The change occurs due to an increase in the fat content of the milk as a feed progresses – hence the ‘creamy’ label attached to hind-milk. It isn’t simply the case of the longer the feed, the fattier the milk, however. A study published in Experimental Physiology demonstrates that the fat content is related to the ‘emptiness’ of the breast: the less milk it contains, the greater the proportion of fat in the milk1. This means that if a baby has a 4oz feed when the breast is only storing half its potential milk volume, it will contain more fat than a 4oz feed taken when the breast is three-quarters full.

The amount of fat in your milk therefore varies considerably throughout the day, depending on the time since the last feed, the amount of milk consumed at the last feed, the amount of milk consumed at the current feed… It sounds complicated – how on earth do you make sure that your baby is getting enough? The short answer is that you don’t need to. Whilst fat is an important constituent of your baby’s diet, so are protein and carbohydrate, and both of these are found in the watery rather than the fatty part of the milk. The evidence also suggests that weight gain is related simply to the volume of milk consumed, and not its fat content2, underlining the nutritional importance of all the components of breast milk.

If you are breastfeeding on demand, the bottom line is that you don’t need to worry about the ‘type’ of milk your baby is getting. Babies can show a wide variety of feeding patterns, suckling for varying lengths of time and at varying intervals over the course of a day, and maintain a healthy weight3. The terms ‘fore-milk’ and ‘hind-milk’ do have their place: in scientific studies, they are used to describe the samples of milk taken at the beginning and end of a feed. In more general usage, however, they often produce a confused and inaccurate picture. They split milk into two types (when there is actually only one), and imply that the fat contained in milk is somehow more nutritious than the rest of it. In fact, nutrients that are important for health and growth are contained in both components of breast milk, so the implication that the fatty part is for ‘eating’ and the watery part for ‘drinking’ is somewhat misleading. The important thing to remember is that ensuring your baby’s thirst and appetite are satisfied is not a complicated undertaking – it’s simply a matter of letting her feed when she wants to.

  1. Exp Physiol. 1993 Nov;78(6):741-55.
  2. Paediatr Perinat Epidemiol. 2002 Oct;16(4):355-60.
  3. Pediatrics. 2006 Mar;117(3):e387-95.Click here to read