Zuccato E, Andreoletti M, Bozzani A, Marcucci F, Velio P, Bianchi P, Mussini E
Eur J Clin Invest. 1983 Jun;13(3):261-6. doi: 10.1111/j.1365-2362.1983.tb00098.x.
Lactose malabsorption, by the breath hydrogen test, and lactose intolerance (presence of symptoms) were studied in twenty healthy Italian subjects after intake of 12.5, 25 and 50 g lactose, whole milk and low-lactose milk. A rise in respiratory concentration of hydrogen (greater than 20 ppm) (malabsorption) was found in fifteen subjects after 50 g lactose, in thirteen after 25 g and in seven after 12.5 g. Symptoms generally occurred in subjects presenting a rise in respiratory hydrogen excretion, but such a rise was often observed without symptoms. Thirteen subjects presented symptoms after 50 g lactose, but only three after 25 g and one after 12.5 g. Whole milk (500 ml) gave a lower incidence of lactose malabsorption than 25 g lactose (7/20 versus 13/20, P less than 0.05) and more subjects developed symptoms (7/20 versus 3/20, NS). Low-lactose milk produced no malabsorbers and one intolerant. Breath methane was detected constantly in seven subjects and in three on some of the days of observation. Respiratory methane excretion generally appeared to be unrelated to lactose ingestion.
通过呼气氢试验研究了20名健康意大利受试者在摄入12.5克、25克和50克乳糖、全脂牛奶及低乳糖牛奶后乳糖吸收不良情况以及乳糖不耐受（症状出现情况）。50克乳糖后，15名受试者出现呼气氢浓度升高（大于20 ppm）（吸收不良）；25克乳糖后，13名受试者出现；12.5克乳糖后，7名受试者出现。症状通常出现在呼气氢排泄增加的受试者中，但这种增加情况也常无明显症状。50克乳糖后，13名受试者出现症状，但25克乳糖后仅3名，12.5克乳糖后仅1名。500毫升全脂牛奶导致乳糖吸收不良的发生率低于25克乳糖（7/20对比13/20，P小于0.05），且出现症状的受试者更多（7/20对比3/20，无显著性差异）。低乳糖牛奶未导致吸收不良者，仅1名不耐受者。在7名受试者中持续检测到呼气甲烷，在3名受试者的部分观察日检测到呼气甲烷。呼气甲烷排泄通常似乎与乳糖摄入无关。
