ALLERGY HOTLINE COLUMNS
LI in Children
Diarrhea, gas, bloating, foul-smelling stools. Bad enough in an adult, far worse when the victim is an eighteen-month-old. As a parent you have to wonder not just, "is this lactose intolerance?" but, "is this permanent?" Those questions are among the toughest to answer, so letís break them down to make them more manageable.
First, at what age can you expect LI to begin? Studies from around the world have shown a correlation between early onset of LI and the likelihood that LI is nearly universal as adults. In Bangladesh, 59% of children under three are LI, 10% of children under eighteen months. The numbers are similar in Singapore and Thailand. Native Americans in Canada and Peru show an effect about half as large.
For most other groups, however, early onset of LI is rare. And even children of non-white ethnic heritages in the U.S. have extremely low percentages of LI. While the loss of lactase due to natural aging, known as Primary LI, can never quite be ruled out, it is unlikely at best.
If that is true, does that also mean that LI is rare? No, because the intestines can temporarily lose their ability to manufacture the lactase enzyme for any number of reasons. The number one reason for children is diarrhea itself when it is caused by a rotavirus infection, also known as acute gastroenteritis, or your basic "stomach flu." This is known as Temporary or Secondary LI and it is extremely common. One pediatric gastroenterologist estimated that at any given time, 10-15% of the children in his practice suffer from some kind of infectious condition and 10-15% of that group will become LI. Given the number of infections a child will typically get over the two years of greatest susceptibility, the odds that at least one of them will develop into Secondary LI are high indeed.
There is no cure for this, or rather there are a variety of them. The first priority is curing whatever the underlying problem is. Most "stomach flus" have a natural course of two to three weeks with standard treatment, but other problems may be more serious and need more time.
The child must be taken completely off of milk and milk products for this entire time. That includes both motherís milk as well as cowís milk. Any of the standard soy milk formulas (or soy milks, if the child is old enough for them) or equivalents can be used instead.
Only after the intestines are healthy can the delicate villi (the finger-like projections on the inside of the small intestine that actually manufacture the lactase) begin to heal. This is a separate process and can easily take another two to three weeks. You can start reintroducing milk in small amounts into the childís diet at the end of that time and see what the reaction is. If the diarrhea reoccurs, hold off for another several days. Yogurt, which is often better tolerated than other milk products, may be used for older children.
In most cases, Temporary LI will live up to its name, and normal feeding can resume from then on. (Until the next time. A few children may go through a pattern of intestinal problems and become LI several times through their toddlerhood.)
However, in those populations in which early onset of Primary LI is most likely a rotavirus infection may result in permanent loss of the lactase making ability, even in children as young as six months. Asian children seem particularly subject to this permanent loss.
Overall, though, a bout of LI is just one of those things that children go through while they are young. Itís uncomfortable for them, and difficult for parents, but itís not really serious and does no long-term harm.