Symptoms of Lactose Intolerance in Newborns
Aug 16, 2021
Source: Cainiu Health
Dr. Ma Yan
Introduction
1. Developmental delay: During this rapid growth phase, infants require adequate nutrition from their food intake; failure to absorb essential nutrients can easily lead to developmental delay.
2. Diarrhea: Lactase—the enzyme required to digest lactose—gradually diminishes in the human body when not regularly utilized.
3. Abdominal distension: Undigested lactose passing through intestinal peristalsis into the colon can be fermented by colonic bacteria.
Lactose intolerance refers to a condition in which the body fails to produce lactase—the enzyme required to break down lactose. Undigested lactose passes into the intestines, where gut bacteria ferment it into lactic acid. This disrupts the alkaline environment of the intestine, prompting the gut to secrete large amounts of alkaline digestive fluids to neutralize the lactic acid. So, what are the symptoms of lactose intolerance in newborns? Below, we address this question.
Symptoms of Lactose Intolerance in Newborns
1. Growth Delay
During infancy, rapid physical development demands adequate nutrient absorption from ingested food. In lactose-intolerant infants, poor nutrient absorption may lead to growth delay—commonly manifested as consistently shorter stature compared with peers of the same age. If suspected, medical evaluation—including measurement of serum levels of essential elements—can help confirm the diagnosis and guide appropriate interventions. Moreover, feeding low-lactose formulas may impair calcium absorption in the small intestine. Over time, this can result in bone metabolism disorders such as rickets, osteomalacia, and osteoporosis.
2. Diarrhea
Diarrhea is a common symptom of lactose intolerance in infants. Lactase activity naturally declines when not regularly stimulated—especially after prolonged consumption of cow’s milk, which may trigger lactase regeneration. Some infants develop diarrhea even after minimal lactose exposure, although symptoms typically appear only after exceeding a certain threshold intake. Without early diagnosis, diarrhea and lactose intolerance may form a vicious cycle, potentially progressing to chronic or persistent diarrhea. Severe cases may cause electrolyte imbalances and deficiencies in trace elements such as calcium and zinc.
3. Abdominal Distension
Abdominal distension is another frequent manifestation of lactose intolerance in infants. When undigested lactose reaches the colon via intestinal peristalsis, colonic bacteria ferment it into lactic acid, acetic acid, and hydrogen gas. The resulting gas accumulation causes bloating, abdominal pain, and increased flatulence—further exacerbating symptoms. Additional manifestations may include cardiac arrhythmias, difficulty concentrating, oral ulcers, and various allergic reactions—all attributable to lactose intolerance. In severe cases, prompt medical consultation is advised.
The above outlines the key symptoms of lactose intolerance in newborns. We hope this information is helpful to you.
