中国儿童乳糖不耐受发生率的调查研究

随机选择北京、上海、广州和哈尔滨４大城市的３～１３岁健康儿童１１６８名,采用乳制品摄入量频率调查、乳糖耐量试验和氢呼气试验的方法,研究了中国儿童乳糖酶缺乏和乳糖不耐受的发生率。结果表明：３～５岁,７～８岁和１１～１３岁组儿童中,乳糖酶缺乏的发生率分别为３８．５％、８７．６％和８７．８％。乳糖不耐受发生率分别为１２．２％、３２．２％和２９．０％。中国４大城市儿童乳糖酶降低或消失发生的年龄在７～８岁。当儿童食用５０ｇ奶粉（含１３～１４ｇ乳糖）时,吸收不良和不耐受的发生率显著下降,但学龄儿童中仍有３９％～４１．７％为吸收不良、牛奶不耐受症状发生率１４％～１６．７％。研究未发现乳糖酶缺乏的发生和儿童的喂养史、乳品摄入史有关     

青少年摄入不同剂量乳糖与氢呼气量关系的研究

目的　探讨广东青少年摄入不同剂量乳糖与氢呼气量的关系。方法　采用不同剂量乳糖进行氢呼气试验。选择广州、珠海、佛山、韶关 4个城市 7～ 1 8岁健康的中小学生 92 6名 ,摄入2 5 0 0g纯乳糖进行氢呼气试验 ,对检出为乳糖酶缺乏者 ,先后服用含乳糖 1 2 5 0、6 2 5g的奶粉 ,进行牛奶氢呼气试验。结果　广东省中小学生乳糖酶缺乏率为 73 7%。乳糖酶缺乏者出现最大呼氢峰值的年龄是 1 3岁 ,其中乳糖不耐受者出现最大呼氢峰值的年龄是 1 2岁。摄入乳糖 2 5 0 0、1 2 5 0、6 2 5g的呼氢峰值分别是 6 2 1 1、4 0 89、37 92mol/L ,差异有显著性 (U1 =1 6 76 3 5 0 ,U2 =5 739 0 0 ,P <0 0 1 )。摄入 2 5 0 0g乳糖受试组乳糖不耐受的呼氢峰值明显高于乳糖吸收不良者 (U =2 31 1 4 0 0 ,P<0 0 5 )。摄入 2 5 0 0、1 2 5 0、6 2 5g乳糖出现最大呼氢峰值时间分别是在摄入后 1、2、3h ,最高的乳糖酶缺乏检出率分别是在摄入后 2、2、3h。结论　氢呼气试验的呼氢峰值随乳糖摄入量的减少而降低 ,乳糖酶缺乏发生时间有随乳糖摄入量的减少而推后的趋势     

乳糖和果糖吸收不良

乳糖吸收不良乳糖是奶类中特有的碳水化合物。乳糖必须经过小肠上皮细胞刷状缘的乳糖酶水解变为半乳糖和葡萄糖才能被吸收。由于小肠粘膜上皮细胞刷状缘乳糖酶缺乏,导致乳糖吸收不良(LM)和伴有胃肠症状。乳糖酶缺乏的人常因反复检查未见消化道器质性病变而归于胃肠功能紊乱。因此明确LM的发生情况,采用有效措施对临床有重要意义。一、发生率:目前世界上约2/3的人存在不同程度的LM或不耐受,发生率有明显的种族差异。白种人约占5％～20％,黑种人约占70～80     

0～6岁儿童乳糖酶缺乏的现状与健康关系的研究

[目的]探讨上海地区O～6岁儿童乳糖酶缺乏的现状以及与其生长发育的关系. [方法] 采用JY-po-eolor Gal尿半乳糖测定试剂盒进行检测. [结果]O～6岁儿童乳糖吸收不良的发生率为47.4%,乳糖不耐受发生率为16.5%,其发生率均随儿童年龄的增加而上升,各年龄组之间差异有显著性(P＜O.01),乳糖酶的缺乏与儿童的体格发育及营养性疾病的发生有一定的关系. [结论]要重视儿童乳糖酶缺乏的高发现状,必须早期诊断、有效干预,同时建议伴有钙、铁等营养素缺乏的患儿应适量给予相应的补充,以促进儿童正常的生长发育.     

沧州地区儿童乳糖酶缺乏现状与体格发育关系的研究

目的：探讨沧州地区儿童乳糖酶缺乏的现状及其与体格发育的关系。方法选取2015年1月至2016年2月来沧州市中心医院门诊体检的210名3～14岁儿童为研究对象,按年龄段分为3～5岁组（125例,男性32例,女性93例）、6～10岁组（49例,男性38例,女性11例）以及11～14岁组（36例,男性24例,女性12例）。乳糖酶采用JY-po-color Gal尿半乳糖测定方法,分析不同年龄段乳糖酶缺乏的检出率,并对同年龄段组间的骨密度和骨钙蛋白进行比较。结果在210名儿童中乳糖酶缺乏检出率3～5岁组为52．0％,6～10岁组为65．3％,10～14岁组为83．3％,不同年龄组间检出率存在显著性差异,随着年龄的增长检出率呈逐渐升高趋势（χ2＝32．984,P＜0．05）;农村儿童乳糖酶缺乏检出率显著高于城市儿童（χ2＝29．621,P＜0．05）;不同性别间儿童乳糖酶缺乏检出率未见显著性差异（χ2＝0．144,P＞0．05）。乳糖缺乏与正常儿童每日饮奶量、饮奶率比较均有显著性差异（t值分别为15．845、11．363,均P＜0．05）。与同年龄组乳糖酶正常儿童相比,乳糖酶缺乏者的骨钙蛋白和骨密度均显著降低（χ2值分别为4．354、5．041、4．861;2．836、3．845、2．983,均P＜0．05）。结论乳糖酶缺乏症会造成儿童规避饮奶或饮奶后出现腹泻、腹痛等症状,造成奶制品中营养物质流失,对儿童生长发育带来不良影响。     

广州市198名儿童乳糖耐量研究

乳糖广泛存在于乳制品中 ,是奶里重要的营养成分之一 ,乳糖能否在体内消化吸收 ,将直接影响着奶类的营养成份的利用 ,国内不断有乳糖酶缺乏的研究报道〔1-3〕,但在广州市尚没有 3～ 13岁儿童乳糖酶缺乏的研究报道。为了解广州市儿童乳糖酶缺乏的现状 ,我们进行了儿童乳糖呼气试验。1　对象与方法1.1　对象 :在广州市区选取本地健康、无胃肠疾病且 1周内无服食药物的学生 ,获得有效人数 3～ 4岁 73人 ,7～ 8岁 6 6人和12～ 13岁 5 9人 ,共 198人。1.2　材料和仪器1.2 .1　乳糖 :食品级 ,美国ＡＭＰＣ .Ｉｎｃ公司。1.2 .2　奶粉 :市售产品 (…     

用双标稳定同位素技术分析乳糖酶缺乏者小肠粘膜乳糖酶活性

目的　应用双标稳定同位素1 3C 乳糖2 H 葡萄糖负荷试验对乳糖酶缺乏者小肠粘膜乳糖酶活性进行定量分析。方法　选用4 3名乳糖酶缺乏者(呼气ΔH2 浓度>2 0 μmol mol)作为实验对象,根据乳糖不耐受症状记录分为乳糖吸收不良组(LM)和乳糖不耐受组(LI)。以2 5g1 3C 乳糖和0 . 5g2 H 葡萄糖作为受试底物,分析受试者摄入底物之后各时点血浆中总葡萄糖、1 3C 葡萄糖和2 H 葡萄糖浓度,并计算各时点1 3C 葡萄糖2 H 葡萄糖吸收百分率的比值,以4 5min、6 0min、75min三个时点所得比值的均值作为乳糖消化指数(LDI)来反应小肠乳糖酶活性。结果　乳糖吸收不良组和乳糖不耐受组两组各时点血浆总葡萄糖、1 3C 葡萄糖无显著性差异,乳糖吸收不良组的乳糖消化指数显著高于乳糖不耐受组(0 . 4 7±0 .15vs 0 . 34±0 . 14 ) ;乳糖消化指数与6h累积H2 呼出量无显著性相关关系(r=0 . 12 ,P =0 .4 6 ) ;经H2 呼气试验结果判定为乳糖酶缺乏的个体,经1 3C 乳糖 2 H 葡萄糖负荷试验分析显示小肠粘膜仍存在一定乳糖酶活性。结论　采用双标稳定同位素1 3C 乳糖2 H 葡萄糖负荷试验可以准确、灵敏地定量分析小肠粘膜乳糖酶活性,同时可以计算体内乳糖消化量。     

外源性乳糖酶对乳糖吸收不良者的干预研究

本研究主要观察有乳糖吸收不良者以外源性乳糖酶补充对乳糖吸收不良和不耐受症状的改善。以２５ｇ乳糖耐量试验筛选出乳糖吸收不良和乳糖不耐受者（出现腹痛、腹泻等胃肠不适症状）作为实验对象,受试者分别服用４００ｍｌ脱脂奶和４００ｍｌ脱脂奶＋乳糖酶９０００ＦＣＣＬＵ,观察４小时内５个小时点呼气中的氢气浓度和不耐受症状。结果显示：外源性乳糖酶干预使受试者乳糖吸收不良发生率由１００％降至４８．９％,不耐受症状发生     

正常成年人对牛奶和酸牛奶中乳糖吸收程度和不耐受程度的调查

采用无损性、灵敏的氢气呼吸试验,对30名在摄入半磅牛奶和半磅酸牛奶后的成人乳糖吸收和不耐受程度进行了观察。结果表明。摄入牛奶后,4人牛奶乳糖完全吸收(13.3％),26人乳糖吸收不良(86.7％)。其中1人(3.3％)轻度吸收不良,16人(53.3％)中度吸收不良,9人(30％)重度吸收不良。 饮牛奶者和改饮酸牛奶者的不耐受率和不耐受指数分别为53.3％,6.7％和0.9,0.067。 牛奶乳糖吸收不良者在8小时内平均多排出的氢气量为60.34±30.57(ml),酸牛奶为14.97±13.64(ml)(p<0.01),提示酸牛奶中约75％的乳糖转化而吸收。酸牛奶有“自动消化乳糖”的作用,可弥补内源性乳糖酶的缺乏。     

鲜奶和酸奶中钙的吸收

近来发现乳糖酶缺乏者患骨质疏松的病例不断增加,这可能是由于乳糖酶缺乏者力求避免吃乳制品,和/或由于乳糖的吸收不良减少了乳中钙的吸收。已知酸奶中的乳糖可被乳糖酶含量低者消化吸收,但     

Respiratory hydrogen excretion as a parameter for lactose malabsorption in children.

Respiratory hydrogen excretion was measured during tolerance tests with lactose, glucose plus galactose, and skim milk in 52 children, 4 to 15 years of age. Ten children appeared to be lactose-malabsorbers, as reflected by increased respiratory hydrogen excretion after administration of 2 g lactose per kilogram, maximum 50 g. Skim milk, equivalent to 0.5 g lactose per kilogram was administered to all lactose-malabsorbers. Eight children were tolerant and two children were "intolerant" for this physiological amount of lactose when administered as skim milk. Disaccharidase activities of jejunal biopsies were determined in all 10 children with lactose malabsorption. Lactase activity was deficient in nine children and normal in one child. The increase of blood glucose during the lactose tolerance test did reflect lactose malabsorption less accurately than the respiratory hydrogen excretion.     

Incidence of lactose malabsorption in the population 6-18 years of age

Breath test was performed in 664 school-aged children in order to measure lactose malabsorption. The first screening showed that 23.4% of the children evidenced malabsorption of milk sugar. In these children further stool examination for Giardia lamblia infection, and saccharose breath test was performed to identify more complex absorption problems. The remaining 146 children were tested again after a period of 3-9 month and 45.8% of this population showed lactose malabsorption. In conclusion the authors determined that 10.1% of school aged children were permanently hypo- or alactasic. During the examination, they measured the approximate consumption of milk considering the quantity of milk intake showed that the consumption of milk and lactose malabsorption were not closely related normal and abnormal absorption among children who would not normally consume milk.     

Dietary manipulation of postprandial colonic lactose fermentation: I. Effect of solid foods in a meal

The effect of adding solid foods--cornflakes, banana and hard-boiled egg--to a meal with 360 ml of intact milk containing 18 g of lactose was investigated in 13 lactose-malabsorbers and 10 lactose-absorbers chosen from 36 Guatemalan adults screened for their capacity to digest and absorb completely the lactose in this volume of milk. A six-hour hydrogen breath test was used as the index of carbohydrate absorption. Minimal breath H2 was excreted by lactose-absorbers with either the intact milk alone, the intact milk with solid foods, or lactose-prehydrolyzed milk with solids. In lactose-malabsorbers, however, the 6-h excretion of H2 with intact milk plus solid food was intermediary between milk alone and prehydrolyzed milk with solids. A relative net reduction of 47% in lactose malabsorption was produced by adding food, and the peak-rise in breath H2 was delayed by 2 hours. A physiological consequence of taking solid foods along with milk is a slower rate of colonic fermentation, and this may be the basis for reducing gastro-intestinal symptoms in lactose-intolerant malabsorbers.     

Lactose absorption and consumption in Cura?ao schoolchildren

As an initial step to evaluate the school additional-nourishment program, which provides milk to schoolchildren, a study was conducted in the fall of 1984 on 729 black schoolchildren (aged 8-10 y) in Cura?ao, for whom lactose consumption and absorption were determined. A food frequency questionnaire was used to determine lactose consumption, and a breath-hydrogen test was used to determine lactose absorption after a physiological load of 0.5 g lactose/kg body wt was administered in the form of standardized irradiated whole milk. An increase in breath-hydrogen of 20 ppm indicated lactose malabsorption; 14% of the children were malabsorbers of lactose. No relationship was found between lactose malabsorption and lactose consumption, as estimated from the questionnaire. Possible reasons for the lower-than-expected prevalence of lactose malabsorption in this population are the use of a physiological dose of lactose, and the fact that this population is well nourished and free from significant parasitism and other endemic diseases.     

Lactose malabsorption in Australian Aboriginal children

The purpose of this study was to determine the prevalence of lactose malabsorption in healthy full-blood Australian Aboriginal children. Sixty-three Aboriginal subjects and forty-six non-Aboriginal controls ranging in age from six to 14 years were tested using the breath hydrogen method. Seventy percent of the Aboriginal subjects were found to be lactose malabsorbers and 9% of the controls. The results provide strong evidence that the majority of full-blood Aboriginal children are lactose malabsorbers and that the characteristic is well-established by 6-7 years of age, in common with most other non-Western populations.     

Comparison of symptoms after the consumption of milk or lactose-hydrolysed milk by people with self-reported severe lactose intolerance

BACKGROUND: Ingestion of a large dose of the milk sugar lactose--for example, the 50 g load in 1 liter of milk--causes symptoms such as abdominal pain, diarrhoea, bloating and flatulence in the majority of people with lactose malabsorption. It is uncertain whether the ingestion of more common doses of lactose, such as the amount in 240 mol (8 oz) of milk, causes symptoms. Some people insist that even smaller quantities of milk, such as the amount used with cereal or coffee, cause severe gastrointestinal distress. METHODS: In a randomized, double-blind, cross-over trial, we evaluated gastrointestinal symptoms in 30 people (mean age, 29.4 years; range 18-50) who reported severe lactose intolerance after ingesting less than 240 ml of milk. The ability to digest lactose was assessed by the subjects' end-alveolar hydrogen concentration after they ingested 15 g of lactose in 250 ml of water. Subjects then received either 240 ml of lactose-hydrolysed milk containing 2% fat or 240 ml of milk containing 2% fat and sweetened with aspartame to approximate the taste of the lactose-hydrolysed milk; each type of milk was administered daily with breakfast for a 1-week period. Using a standardized scale, subjects rated the occurrence and severity of bloating, abdominal pain, diarrhoea, and flatus and recorded each passage of flatus. RESULTS: Twenty-one participants were classified as having lactose malabsorption and nine as being able to absorb lactose. During the study periods, gastrointestinal symptoms were minimal (mean symptom-severity scores for bloating, abdominal pain, diarrhoea, and flatus between 0.1 and 1.2 [1 indicated trivial symptoms, 2 indicated mild symptoms]). When the periods were compared, there were no statistically significant differences in the severity of these four gastrointestinal symptoms. For the lactose malabsorption group, the mean (+/- SEM) difference in episodes of flatus per day was 2.5 +/- 1.1 (95% confidence interval, 0.2-4.8). Daily dietary records indicated a high degree of compliance, with no additional sources of lactose reported. CONCLUSIONS: People who identify themselves as severely lactose-intolerant may mistakenly attribute a variety of abdominal symptoms to lactose intolerance. When lactose intolerance is limited to the equivalent of 240 ml of milk or less a day, symptoms are likely to be negligible and the use of lactose digestive aids unnecessary.     

Lactose malabsorption in preschool black children

One hundred sixteen healthy black children ages 13 to 59 months, representing high and low socioeconomic deciles, were studied for lactose malabsorption. A fasting lactose tolerance test using 2 g of lactose/kg of body weight was carried out. Glucose was determined at 0, 15, 30, and 60 min. Of the 116 preschoolers 34 (29%) evidenced lactose malabsorption as determined by a blood glucose rise of less than 26 mg/100 ml. Clinical signs of diarrhea, gas, and cramps were noted singly or in combination in 18% of the 34 lactose-malabsorbing children. Of the 82 lactose absorbers, 12% demonstrated similar signs. The nature and length of the initial infant milk feeding failed to show any relationship to the onset of malabsorption. Current milk drinking patterns were reported as being similar. Eight-seven percent of the malabsorbers and 92% of the absorbers report drinking 240 ml or more of milk/day. Socioeconomic status, education, marital status, and medical assistance of the parent is similarly distributed between lactose absorbers and malabsorbers.     

Lactose malabsorption in Bangladeshi village children: relation with age, history of recent diarrhea, nutritional status, and breast feeding.

The prevalence of lactose malabsorption (LM) among Bangladeshi village children has been determined using the recent developed breath hydrogen test. Initial hospital-based comparison studies showed general agreement between the breath hydrogen test and a modified lactose tolerance test. Two hundred thirty-four children, stratified by age, nutritional status, and history of recent diarrhea then participated in the field study. LM was diagnosed in more than 80% of children over 36 months of age but in none of the children under 6 months. Rates of LM were significantly increased in children with a history of recent diarrhea and a greater proportion of children in some age groups evidenced malabsorption in association with acute undernutrition. In the weanling age group children who were still breast feeding had a lower rate of LM than fully weaned subjects.     

Lactose maldigestion and milk intolerance in healthy Greek schoolchildren

The prevalence of lactose maldigestion in Greek adults is 75% but the age at which the lactase activity starts declining is not known. The prevalences of lactose maldigestion and intolerance were investigated in 150 randomly selected Greek children 5-12 y old by using breath-hydrogen analysis after ingestion of lactose (2 g/kg body wt, maximum 50 g) or 0.240 L of milk. Prevalence of lactose maldigestion increased with age (y = -7.30 + 6.49x, r = 0.88, P = 0.004), being 29.4% and 80.0% at ages 5 and 12 y, respectively. Before testing, the reported prevalences of milk-related symptoms by children with high and low lactose-digestion capacity were 21.1% and 39.7% (chi 2 = 5.96, P = 0.015), respectively. However, the corresponding prevalences of lactose intolerance after ingestion of milk were 7.3% and 8.6% (chi 2 = 0.1, P = 0.72) and only three children had a delta H2 greater than or equal to 20 ppm postprandially. Although intestinal lactase activity declines before age 5 y and many Greek children report milk-related symptoms, true malabsorption and intolerance of lactose after a glass of milk is rarely seen at this age.