[Importance of nutritional status in digestion capacity and lactose tolerance]

The aim of this study is to determine the capacity of undernourished patients to digest and tolerate the lactose in milk administered by tube-feeding. It was a controlled double-blind crossover trial in 25 hospitalized patients who required enteral feeding due to medical reasons. They were divided in two groups differing by nutritional status: 10 patients in Group 1 were malnourished with a mean weight for height of 69% (+/-15% SD) of their ideal one; Group 2 had 15 well nourished patients (mean weight for height of 103 +/- 15%). Each patient received two dietary treatments: intact milk and hydrolyzed milk (> 90% of lactose hydrolyzed). Lactose digestion was measured by the hydrogen breath test. Hydrogen excretion with intact milk was 505 +/- 117 ppm in Group 1 versus 58 +/- 15 ppm in the control group. With hydrolyzed milk, these values were 53 +/- 27 and 14 +/- 23, respectively. The scoring of symptoms after drinking intact milk was 4.3 +/- 0.7 in Group 1 vs 1.5 +/- 0.3 in Group 2, and they were lower with hydrolyzed milk (0.5 +/- 0.2 vs 0.3 +/- 0.2 respectively). The undernourished group had a higher incidence of both lactose maldigestion (p < 0.0001) and lactose intolerance (p < 0.001) than the control group. Our results strongly suggest that undernourishment is accompanied always or almost always by lactose intolerance.