Bouhnik Y, Attar A, Joly F A, Riottot M, Dyard F, Flourié B
Service de Gastroentérologie et d'Assistance Nutritive, Hôpital Lariboisière, Paris, France.
Eur J Clin Nutr. 2004 Mar;58(3):462-6. doi: 10.1038/sj.ejcn.1601829.
Faecal bifidobacteria and lactobacilli, perceived as exerting health-promoting properties, may be increased by ingestion of high-dose lactulose in humans. The effects of low and well-tolerated doses of lactulose are not well known. The aim of the study was to assess the effects of prolonged low-dose lactulose administration on faecal bifidobacteria and selected metabolic indexes potentially involved in colonic carcinogenesis.
In all, 16 healthy volunteers were included in this controlled, randomised, double-blind, parallel group trial. Participants ingested lactulose or placebo (sucrose) at a dose of 5 g b.i.d. for 6 weeks. Stools were regularly collected at baseline (d0), and after 3 (d21) and 6 (d42) weeks of sugar ingestion. Tolerance was evaluated using a daily chart.
Faecal bifidobacterial counts were higher in lactulose than in sucrose group (P=0.03). Lactulose ingestion led to a significant increase in faecal bifidobacteria counts from d0 to d21 and d42 ((m+/-s.e.m.) 8.25+/-0.53, 8.96+/-0.40 and 9.54+/-0.28 log colony-forming units/g wet wt (CFU/g), respectively (P=0.048)). Placebo ingestion did not lead to any faecal bifidobacterial count change. Total anaerobes, Lactobacillus and pH were not significantly changed throughout the study in the two groups. Neither faecal bile acids nor neutral sterols were modified by lactulose. Excess flatus was more common in the lactulose group (P=0.03), but was very mild. Bloating and borborygmi did not differ between both the groups.
A measure of 10 g lactulose/day increases faecal bifidobacterial counts, and lactulose fulfils the criteria requested to be considered as a prebiotic.
被认为具有促进健康特性的粪便双歧杆菌和乳酸杆菌，可能会因人类摄入高剂量乳果糖而增加。低剂量且耐受性良好的乳果糖的效果尚不清楚。本研究的目的是评估长期低剂量服用乳果糖对粪便双歧杆菌以及可能参与结肠癌发生的选定代谢指标的影响。
共有16名健康志愿者参与了这项对照、随机、双盲、平行组试验。参与者每天两次服用5克乳果糖或安慰剂（蔗糖），持续6周。在基线期（第0天）以及摄入糖类3周（第21天）和6周（第42天）后定期收集粪便。使用每日记录表评估耐受性。
乳果糖组的粪便双歧杆菌计数高于蔗糖组（P = 0.03）。从第0天到第21天和第42天，摄入乳果糖导致粪便双歧杆菌计数显著增加（（平均值±标准误）分别为8.25±0.53、8.96±0.40和9.54±0.28 log菌落形成单位/克湿重（CFU/g），P = 0.048）。摄入安慰剂未导致粪便双歧杆菌计数发生任何变化。在整个研究过程中，两组的总厌氧菌、乳酸杆菌和pH值均无显著变化。乳果糖未改变粪便胆汁酸和中性固醇。乳果糖组中肠胃胀气更为常见（P = 0.03），但非常轻微。两组之间腹胀和肠鸣音没有差异。
每天服用10克乳果糖可增加粪便双歧杆菌计数，且乳果糖符合被视为益生元的要求标准。
