Half a year ago, I met a baby who had just turned 6 months old in the clinic, who had been seen for more than 20 days because of persistent diarrhea. After a few days of antibiotics, the white blood cells in the stool were gone, so the antibiotics were discontinued, but the baby’s diarrhea did not stop, and it even “got worse”. The parents followed the doctor’s instructions and took oral medication and different kinds of probiotics, but the condition did not improve. The child’s mother asked me anxiously, “Doctor, is our baby still suffering from enteritis? Should we continue to take antibiotics? Because of diarrhea, we are afraid to feed our baby anything but formula, and he is losing weight. Please prescribe some useful medicine.” After examining the baby, I smiled and told them, “Don’t be anxious, I won’t prescribe any other medicine for the baby, you should stop the current formula and go buy special diarrhea formula to feed the baby, and you can continue to take probiotics and Simethicone to see how it works.” Two days later, I received a phone call from the baby’s mother with a very excited voice: “Doctor, my baby’s stools have formed and are much less frequent, we are very happy!” I told the parents to stop the Simethicone and continue to feed the diarrhea formula and probiotics. 1 week later, the parents reappeared at my clinic with a big smile, thanking me repeatedly and saying, “Doctor, you’re amazing, the baby’s stools are completely normal, how come the milk works better than the medicine?” I laughed and instructed the parents to feed the diarrhea formula for another week to consolidate the effect. After the diarrhea was completely cured, the baby switched back to regular formula and gradually added complementary foods, and now the baby is 1 week old and growing very well. Milk is better than medicine – I have heard parents say this more than once during my outpatient visits, why? Is it possible that formula can also cure diseases? The answer is yes. The scientific name of this formula for diarrhea is lactose-free milk powder. Both regular formula and breast milk contain lactose, which under normal circumstances can promote the establishment of normal intestinal flora, can assist in the absorption of calcium, and also has the effect of softening stools. The digestion of lactose relies on the lactase enzyme produced at the tip of the brush border of the small intestinal epithelium. In severe diarrhea, due to the rapid and large amount of liquid passing through the intestine, it is easy to cause mechanical damage to the intestinal wall, the brush border of the small intestinal epithelial cells are destroyed and lactase secretion stops, which is secondary to lactase deficiency. At this time, if breast milk and formula containing lactose continue to be consumed, the lactose cannot be digested by lactase and directly enters the large intestine to ferment, generating osmotic pressure and leading to worsening diarrhea. We often see such children in the clinic. Their diarrhea in the early stage may be due to non-infectious factors such as intestinal bacterial or viral infections or cold, improper feeding, etc., but after treatment, the diarrhea is not well controlled, but becomes more and more severe, which is actually caused by secondary lactase deficiency. Just like the baby mentioned earlier, his diarrhea was caused by an intestinal infection caused by eating something unclean, and the intestinal infection was quickly cured, but the lactase deficiency caused by the diarrhea was too severe, resulting in lactose intolerance, and at this time, the parents continued to feed the child with regular formula, and the child’s diarrhea became even more severe. The lactose-free formula replaces lactose with maltose dextrin, which has high caloric energy and low osmotic pressure, to ensure energy supply and facilitate digestion and absorption, interrupting the vicious cycle between lactose intolerance and diarrhea, allowing the intestinal wall cells to “recuperate” and wait until the small intestinal epithelial cells “recover” after a while. “After a while, the small intestine epithelial cells can continue to secrete lactase, and at this point, there is no problem switching back to regular formula or breast milk. Of course, while switching to lactose-free formula, you should pay attention to ensure the intake, maintain the water-electrolyte balance, take oral simethicone or montelukast to protect the gastrointestinal mucosa, and give probiotics to adjust the normal intestinal flora. So, for diarrhea, sometimes it is necessary to choose a formula for diarrhea, and it is not better to eat milk than to take medicine, it is the right choice of lactose-free formula that works!