Dear colleague,
there are no babies with lactose intolerance except those very few with rare diseases of the gut mucosa (e.g. microvillous inclusion disease) who can generally not absorb nutrients. After a severe diarrhoe episode a baby may become lactose-intolerant for a short time but if you totally avoid feeding lactose the gut will not produce lactase. Therefore, the stepwise introduction of lactose is recommended in those kids.

Babies with galactosemia need galactose- and lactose-free feeds either from soybean milk or from meat extracts.
There are many instructions for making soybean milk in the internet: e.g. https://www.youtube.com/watch?v=9ZyeReRF1oI

Good luck.

Dear Sarmin,

To reinforce the previous post from Michael Krawinkel, one has to be very careful about diagnosing lactose intolerance. As you know, all malnourished children with diarrhoea benefit hugely from breast milk although it has a high lactose content, about 70 g/L, much higher than cow milk (about 40 g/L). This shows that lactose is not a big issue in the vast majority of these children, even with diarrhoea.

Dear Sarmin
Again to reinforce what Michael Krawinkel and Andre Briend highlighted and to add a few extra info..
Primary lactase deficiency is an extremely rare problem in infancy and caution should be taken in making the appropriate diagnosis early after birth. Although galactosemia, a rare inherited metabolic disorder, can occur in some babies, the screening test can result in false positives especially in hot conditions, so again care in diagnosis should be taken. Secondary lactase deficiency occur in babies as a temporary condition, as indicated by MK, due to damage to small intestine from infection, medication, or feeding mismanagement, which can cause diarrhoea.

Exclusive breastfeeding up to 6 months, followed by appropriate introduction of complementary food and the continuation of breastfeeding up to 2 years are the feeding recommendation from birth, but in the case of primary lactase deficiency breastfeeding and cows' milk formula are contraindicated due to the presence of lactose, as explained. Soya based formulae are therefore given as an alternative unless there is signi?cant liver disease, when a medium chain triglyceride containing casein based protein hydrolysate is preferred until the liver disease has resolved. Obviously these alternatives are not available in all countries. Michael Krawinkel, I am interested to know more about the meat extract alternative, as I am not familiar with it. In terms of food, most food items are fine, except lactose containing food which mostly include dairy products and some medication with lactose coating.

In the case of secondary lactase deficiency, exclusive breastfeeding should be the continued method of feeding up to 6 months, as breastmilk contains anti-infective properties which will particularly help minimise the diarrhoeal symptoms caused by any intestinal infection. The gut damage slows or stops the lactase production which often cause diarrhoea, which can be life-threatening in very small infants, as it can cause dehydration and rapid weight loss. Hence continuing exclusive breastfeeding is the best course of action unless dehydration becomes severe, then oral dehydration salts also need to be given. If there is no improvement, further investigation will be required.

There is an even more important advantage of breastmilk for infants with diarrhoea: it contains epidermal growth factor which promotes healing of lining of the baby's gut, and regrowth of the damaged microvillae which are the site of production of lactase.

This question of lactose intolerance has been a problem for many years, with poorly informed doctors recommending low lactose formula to infants with diarrhoea, and stopping breastfeeding. Formula companies are gravely at fault for encouraging doctors to believe that such products are necessary.

Overdiagnosis is another problem: in perfectly healthy exclusively breastfed babies whose mothers have a generous supply of milk, the stools may contain lactose, and react positively to tests for sugars. This is just physiological overspill, in the presence of normal lactase activity.

Dear Dr Micheal,
can you provide us with some references and Evidence based articles. as we are facing this obstacle in our setting where pediatricians are frequently prescribing Lactose free formula for chronic diarrhea cases.
Thanks

So true Felicity. Thank you.

Dear colleague,
please find more information under these links:
- http://apjcn.nhri.org.tw/server/APJCN/24%20Suppl%201//S9.pdf
- http://apjcn.nhri.org.tw/server/APJCN/24%20Suppl%201//S21.pdf
I am not aware of any well documented case of lactose intolerance in early infancy except those very few children with gut failure.
Obviously, most lactose intolerance observed in people beyond infancy is triggered by lack of lactose in the diet. In clinical case management of lactose intolerance we recommend the stepwise reintroduction of lactose in the diet in order to stimulate the enzyme. The assumption that lactose in the diet induces intestinal lactase activity is also supported by the observation that dairy products are consumed in many - more affluent - populations in Asia and Africa. Therefore, one should really question the need for lactose-free formula - except for a short period after severe diarrhoea.
This topic is definitively underresearched. I can only send you one abstract from 1997:

Peuhkuri K et al. Age and continuous lactose challenge modify lactase protein expression and enzyme activity in gut epithelium in the rat. J Physiol Pharmacol. 1997;48(4):719-29.

Abstract
The activity of lactase enzyme declines after weaning. This study was to investigate changes in the lactase expression in the whole gastrointestinal tract during the development and the possibility that this and activity can be induced by lactose. Expression of lactase protein in the gut of 1-12-weeks old rats was studied by immunocytochemistry. Possible induction was evaluated by immunohistochemical and biochemical techniques in 8-week-old rats after lactose challenge for seven days. Lactase immunoreactivity was detected only in the small intestine and it decreased 20% during the week after weaning. A steady level of 40% lower than in the sucklings was found in the adult rats. In the lactose-challenged rats the optical density of immunoreactivity increased by about 30% in those that consumed the highest concentration of lactose. In the proximal jejunum, elevation of the enzymatic activity was three-fold. In the rat lactase protein expression decreased rapidly after weaning and expression and activity were induced by lactose-rich diet, most notably in the proximal jejunum.
These findings also explain how breastmilk promotes lactose digestion.

Dear Michael

Thank you for the articles. Regards.