Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Lactose Intolerance”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39Linked to original sources

No difference in symptoms during challenges with homogenized and unhomogenized cow's milk in subjects with subjective hypersensitivity to homogenized milk.

It has been hypothesized that certain consumers tolerate untreated cow's milk, but react to processed (i.e. homogenized and pasteurized) cow's milk although they do not suffer from IgE-mediated cow's milk allergy or lactose intolerance. The aim of the study was to compare the tolerance of unhomogenized and homogenized cow's milk in lactose tolerant adults who had repeatedly experienced better tolerance of unhomogenized than homogenized milk. Forty-four subjects were challenged with homogenized and unhomogenized cow's milk for five days in a randomized, double-blind, cross-over study. No differences in the symptoms during the challenges were found. Roughly half the subjects tolerated the homogenized milk better and the other half tolerated the unhomogenized milk better. The results of this study show no difference in the tolerance of homogenized and unhomogenized milk in adults with self-reported symptoms suggestive of hypersensitivity to homogenized milk.

Abdominal Pain↗

Correlation of lactase activity, lactose tolerance and milk consumption in different age groups.

Small intestinal lactase activity in the health adult is either the same as in early infancy or may drop to very low levels. The behavior of the enzymatic state varies with the ethnic group studied. In those adults with low lactase activity little information is availalbe as to the age at which the lactase decreases. We attempted to determine a) the frequency of low intestinal lactase activity and b) the age at which the change occurs. For this purpose we reviewed in a large number of intestinal biopsies both histologically as well as for disaccharidase activities. The biopsies were obtained from a heterogeneous group of Caucasians, including patients, their siblings and parents. The patients were those with failure to thrive in whom no organic cause could be elicited, and those with the irritable colon syndrome. Patients ranged in age from 6 weeks to 50 years and out of a total of 1, 077 jejunal biopsies, 172 morphologically normal biopsies were selected. The milk drinking habits of 118 subjects and their families were elicited and 31 oral lactose tolerance tests performed. The mucosal lactase activity and sucrase-to-lactase ratio in those 172 individuals were plotted against age. In the first 3 years the mean lactase activity was 32.1 plus or minus 10.1 mumoles/g protein per min and the sucrase-to-lactase ratio was 1.7 plus or minus 0.5 with no change from year to year. However, after age 5 two separate groups emerge. A small group (24.6% of the population) with low lactase activity, and a second group possessing the same mean value for lactase activity as noted in the first 3 years. The low lactase activity group included children and adults with clinical lactose intolerance. These individuals consumed relatively small amounts of milk and when 12 of them were tested with an oral lactose tolerance test the result was a "flat" curve with a maximum rise in blood glucose of 9 plus or minus 3.2 mg/100 ml. The second group consumed more milk averaging 1 quart/day with no discomfort and when 19 were tested with oral lactose tolerance tests the values were normal. This study indicates that low lactase activity in the Caucasian population may make its appearance at the age of 5 years.

Adolescent↗

Modification of colonic fermentation by bifidobacteria and pH in vitro. Impact on lactose metabolism, short-chain fatty acid, and lactate production.

Colonic fermentation plays an important role in the prevention of lactose intolerance and intestinal disorders. The objectives of this study were to evaluate whether supplementation with bifidobacteria modify colonic fermentation of lactose and short-chain fatty acid production and to assess influence of the pH in an in vitro continuous culture system. There was a significantly greater reduction in lactose concentrations at pH 6.7 than that at either pH 6.2 or pH 5.7, accompanied by the highest beta-galactosidase activity and D-lactate production. Bifidus supplementation reduced lactose and D-lactate concentrations and increased acetate production at pH 6.7. The study demonstrates that lactose is rapidly metabolized by colonic bacteria and lactose fermentation in vitro is pH dependent with a maximum rate at pH 6.7. Bifidobacteria supplementation may have the potential to improve lactose fermentation and to manipulate SCFA and lactate production.

Adult↗

Maximum permissive dosage of lactose and lactitol for transitory diarrhea, and utilizable capacity for lactose in Japanese female adults.

This study aims to estimate the tolerable lactose intake which can be utilized in the digestion by lactase and in the fermentation by intestinal microbes in Japanese female adults. The first, the maximum permissive dosage of lactose not to induce transitory diarrhea was estimated based on the oral ingestion of lactose at several dose levels in all the subjects, and compared with that of lactitol which is not hydrolyzed by digestive enzymes. A second lactose tolerance test involving 10 g and 30 g of lactose was carried out in 10 subjects showing resistance to diarrhea, and serum glucose and insulin levels and the amount of hydrogen excreted in the breath were measured for comparison with those of glucose and lactitol. Subjects were 43 Japanese female adults (average: age 20.5+/-2.1 y, weight 51.3+/-5.1 kg) who had not been diagnosed as having either hypolactasia or being lactose intolerant. Serum glucose and insulin levels were scarcely elevated following the ingestion of both 10 g and 30 g of lactose, while the amount of hydrogen excreted in the breath was greatly increased following the ingestion of 30 g of lactose, but these levels were less following the ingestion of 10 g of lactose. In contrast, the ingestion of 15 g of glucose significantly increased blood glucose and insulin levels, while no hydrogen was detected in the breath. The maximum permissive dosage of lactose not to induce transitory diarrhea was 0.72 g/kg of body weight and that of lactitol was 0.36 g/kg of body weight in Japanese adults. The digestive capacity of lactase is less than 10 g of lactose by single ingestion, while intestinal microflora are able to ferment approximately 20-30 g of lactose. In addition, the ingestion of more than 10 g of lactose might be contributed as prebiotics.

Adult↗

Adult-type hypolactasia and regulation of lactase expression.

A common genetically determined polymorphism in the human population leads to two distinct phenotypes in adults, lactase persistence and adult-type hypolactasia (lactase non-persistence). All healthy newborn children express high levels of lactase and are able to digest large quantities of lactose, the main carbohydrate in milk. Individuals with adult-type hypolactasia lose their lactase expression before adulthood and consequently often become lactose intolerant with associated digestive problems (e.g. diarrhoea). In contrast, lactase persistent individuals have a lifelong lactase expression and are able to digest lactose as adults. Lactase persistence can be regarded as the mutant phenotype since other mammals down-regulate their lactase expression after weaning (the postweaning decline). This phenomenon does not occur in lactase persistent individuals. The regulation of lactase expression is mainly transcriptional and it is well established that adult-type hypolactasia is inherited in an autosomal recessive manner, whereas persistence is dominant. The recent findings of single nucleotide polymorphisms associated with lactase persistence have made it possible to study the potential mechanisms underlying adult-type hypolactasia. This work has led to the identification of gene-regulatory sequences located far from the lactase gene (LCT). The present review describes the recent advances in the understanding of the regulation of lactase expression and the possible mechanisms behind adult-type hypolactasia.

Animals↗

Effect of exogenous beta-galactosidase in patients with lactose malabsorption and intolerance: a crossover double-blind placebo-controlled study.

OBJECTIVE: To evaluate the efficacy of the addition to milk, 5 min and 10 h before its consumption, of a lactase obtained from Kluyveromyces lactis in lactose malabsorbers with intolerance. DESIGN: Double-blind, placebo-controlled, crossover study. SETTING: University Hospital. SUBJECTS: In total, 11 male and 19 female (aged from 18 to 65 y, mean age 43.3 y) lactose malabsorbers with intolerance participated. INTERVENTIONS: Each patient underwent three H(2) breath tests, in a random order. We used 400 ml of cow's semiskimmed milk as substrate and a beta-galactosidase obtained from K. lactis. The test A was carried out adding to the milk the enzyme (3000 UI), 10 h before its consumption; the test B was performed adding the beta-galactosidase (6000 UI) 5 min before milk ingestion and the test C was made using placebo. We evaluated the maximum breath H(2) concentration, the cumulative H(2) excretion and a clinical score based on intolerance symptoms (bloating, abdominal pain, flatulence and diarrhoea). RESULTS: Our study showed a significant reduction of the mean maximum H(2) concentration after both test A (12.07 +/- 7.8 p.p.m.) and test B (13.97 +/- 7.99 p.p.m.) compared with test C (51.46 +/- 16.12 p.p.m.) (ANOVA F = 54.33, P < 0.001). Similarly, there was a significant reduction of the mean cumulative H(2) excretion after both test A (1428 +/- 1156 p.p.m.) and test B (1761 +/- 966 p.p.m.) compared with test C (5795 +/- 2707 p.p.m.) (ANOVA F = 31.46, P < 0.001). We also observed a significant reduction of the mean clinical score after both test A (0.36 +/- 0.55) and test B (0.96 +/- 0.85) compared with test C (3.7 +/- 0.79) (ANOVA F = 106.81, P < 0.001). Moreover, with regard to the mean clinical score, there was a significant reduction after test A with respect to test B (Bonferroni's P = 0.03). CONCLUSIONS: Our study shows that in lactose malabsorbers with intolerance, the lactase obtained from K. lactis can represent a valid therapeutic strategy, with objective and subjective efficacy and without side effects.

Adolescent↗

[Gastroenteritis in children. Peroral rehydration, intravenous fluid therapy and nutrition].

In pediatrics, oral rehydration treatment is increasingly used in the management of gastroenteritis, and based on third world experiences, it is becoming used also in hospitals in western countries. In this paper, the advantages, limitations and practical use of oral rehydration treatment are discussed. Clinical examination of dehydrated children is described, and guidelines are given for intravenous fluid treatment. Furthermore, the article reviews modern research on the nutritional management of gastroenteritis. The incidence of secondary lactose intolerance has been dramatically reduced in recent decades, and this necessitates some changes in our traditional nutritional therapy. Rest of the bowels, and removal of lactose from the diet are seldom justified.

Administration, Oral↗

Lactose biosensor based on Langmuir-Blodgett films of poly(3-hexyl thiophene).

An amperometric lactose biosensor was developed by immobilizing lactase (EC 3.2.1.23) and galactose oxidase (GaO) (EC 1.1.3.9) in Langmuir-Blodgett (LB) films of poly(3-hexyl thiophene) (P3HT)/stearic acid (SA) for estimation of lactose in milk and its products to prevent "lactose intolerance". The enzyme immobilized LB film was used as working electrode and platinum as reference electrode. The enzyme electrodes show a linearity 1-6 g/dL of lactose and have a shelf life more than 120 days. The reusability of electrode was found ten times with 3% loss in current response. The enzyme electrode was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and kinetic parameters such as pH, temperature and stability. The working electrode may be used for the estimation of lactose/galactose in food and biological fluids.

Animals↗

Effect of lactic acid bacteria on diarrheal diseases.

Microbial balance is an important factor in the maintenance of intestinal homeostasis, and yogurt or fermented milk supplementation has been proposed to control diarrheal diseases. A number of studies using animal models and clinical studies in humans have confirmed the beneficial effect of such fermented products in case of lactose intolerance, viral diarrhea or antibiotics-associated diarrhea. The mechanisms by which lactic acid bacteria exert their effects are multiple. Bacterial lactase improves the absorption of lactose, but fermented products slow down the intestinal transit facilitating the action of residual intestinal lactase. The transient passage of lactic acid bacteria in the digestive tract may represent a microbial barrier against the development of pathogenic bacteria, probably due to the release of compounds contributing to the maintenance of colonization resistance to pathogens. The beneficial effects are mainly described in the presence of live bacteria, but inactivated bacteria may also present preventive or curative capacities in diarrheal diseases. Moreover, lactic acid bacteria has been described as reinforcing the non-specific immune defence but also specific immunity, particularly the secretory immune system mediated by secretory IgA or IgM in response to particulate infectious antigens and perhaps to soluble food antigens. Other possible mechanisms include the trophic effect on the intestinal layer, and a down-regulatory activity in cow's milk allergy as well as anti-inflammatory effects have also been suggested.

Diarrhea↗

Carbohydrate intolerance.

PURPOSE OF REVIEW: The small intestinal mucosa is highly specialized for terminal digestion of nutrient polysaccharides and disaccharides and absorption of monosaccharides. However, in the case of digestive or absorptive deficiency, symptoms of carbohydrate intolerance result. Significant progress has been made toward defining the molecular genetic mechanisms responsible for several carbohydrate intolerances. RECENT FINDINGS: This review summarizes monosaccharide and disaccharide intolerance conditions and recent clinical and basic science reports related to carbohydrate digestion and membrane transport. Genetic polymorphisms closely associated with lactase persistence/nonpersistence have been identified. Lactose intolerance is capable of preventing the achievement of adequate peak bone mass in susceptible young adults and may predispose to osteoporosis. Recent studies support previous reports that fructose malabsorption is associated with unexplained gastrointestinal symptoms. GLUT2 may be recruited from the basolateral to the apical membrane of enterocytes to facilitate small intestinal fructose absorption. SUMMARY: Knowledge regarding the clinical aspects of and the physiologic mechanisms responsible for specific carbohydrate intolerances has allowed for improved diagnostic and treatment options and has contributed to continuing investigation of intestinal gene expression.

Journal Article↗

Improved lactose digestion and intolerance among African-American adolescent girls fed a dairy-rich diet.

OBJECTIVE: To determine whether African-American adolescent girls who were fed a dairy-rich diet for 21 days could adapt to lactose, experiencing an overall improvement in lactose tolerance as well as a decrease in hydrogen gas production. DESIGN: Twenty-one-day dietary intervention study. SUBJECTS/SETTING: Seventeen of 21 African-American girls (aged 11 to 15 years) enrolled in a calcium metabolism study chose to participate in the lactose tolerance study. Subjects were screened for any diseases, conditions, or medications that might alter calcium metabolism or colonic fermentation. Subjects were housed in a fraternity on the Purdue University, West Lafayette, Ind, campus, and were supervised 24 hours a day. INTERVENTION: Subjects consumed a dairy-based diet averaging 1,200 mg calcium and 33 g lactose per day for 21 days. Lactose digestion was assessed by an 8-hour breath hydrogen test on days 1 and 21, and symptoms of intolerance (abdominal pain, bloating, flatulence, and diarrhea) were evaluated hourly on a ranked scale during the breath hydrogen tests and once each evening during the 21-day feeding period. MAIN OUTCOME MEASURES: A comparison of breath hydrogen production and gastrointestinal symptoms at the beginning and end of the study. STATISTICAL ANALYSES PERFORMED: The Wilcoxon signed ranks test was used to compare the area under the curve for the 2 breath hydrogen tests. Spearman's p test for trend was used to determine whether there was a change in symptoms. All statistical analyses were 2-tailed and significance was set at P = .05. RESULTS: Fourteen of the 17 subjects had lactose maldigestion. Breath hydrogen excretion decreased significantly (P < .03) from the beginning (148.3 +/- 27.0 ppm x hours) to the end (100.7 +/- 19.3 ppm x hours) of the 21-day period. Gastrointestinal symptoms were negligible during both the breath hydrogen tests as were symptoms during the 21-day period. APPLICATIONS/CONCLUSIONS: The diet was well tolerated by the subjects. Furthermore, the decrease in breath hydrogen suggests colonic adaptation to the high-lactose diet. The results indicate that lactose maldigestion should not be a restricting factor in developing adequate calcium diets for this population. The existence of lactose maldigestion does not result in lactose intolerance in this population when it is fed a dairy-rich diet.

Adolescent↗

Follow up study of cow's milk protein intolerant infants.

Over a period of 4 years, 88 infants with cow's milk protein intolerance (CMPI) were followed prospectively in order to evaluate the persistence of CMPI and its relationship between either serum IgE levels or RAST results for cow's milk. After exclusion of lactose intolerance, two positive cow's milk elimination challenge tests were considered diagnostic for CMPI. At the age of 1, 2, 3 and 4 years respectively, 85%, 78%, 49% and 33% of the children still were cow's milk intolerant. Initial serum values of IgE greater than or equal to 10 kU/l indicated a late development of tolerance to cow's milk proteins. At the age of 4 years, 90% of infants with initial IgE levels less than 10 kU/l had become tolerant to cow's milk while this was the case for only 47% of infants with initial IgE levels greater than or equal to 10 kU/l. Initial RAST results for cow's milk bore no obvious relationship to outcome.

Biomarkers↗

[Role of nutrition in acute and long-term therapy of chronic inflammatory bowel diseases].

The clinical picture and course of inflammatory bowel disease are influenced by nutritional abnormalities and malnutrition. Interest at present concentrates on high-fibre low-refined sugar diets, elimination diets with identification of specific food intolerance and low-residue diets. All three failed to show significant positive effects on the course of the disease, need for hospitalisation, surgical procedures required or post-operative recurrence. Only a low lactose diet seems to be justified, since we found lactose intolerance in 25-35% of patients with inflammatory bowel disease, as compared with 5-10% in the normal population. In 25 patients with Crohn's disease (CD) a reduction in inflammatory activity and improvement of nutritional status was obtained with parenteral nutrition (PN). Nevertheless, longer follow up periods revealed no additional benefit in comparison with conventional therapies. Furthermore, the combination of PN and total bowel rest resulted in the same improvement as with PN alone. 25 patients with CD manifesting an acute phase of the condition were treated with tube feeding (TF) as primary therapy. TF reduced CD activity and improved nutritional status in 15 patients with small bowel disease, whereas the patients with colonic disease and extraintestinal manifestations did not react. A comparison of the effect of PN and TF in 10 patients with CD showed no significant difference with regard to clinical course and objective parameters. In view of the high costs and risks of complications of PN, TF is recommended as primary therapy for the acute phase of CD. The importance of substitution therapy, especially of vitamin D, is documented.

Colitis, Ulcerative↗

Cow's milk protein intolerance in infants under 1 year of age: a prospective epidemiological study.

Incidence and clinical manifestation of cow's milk protein intolerance (CMPI) were studied in 1158 unselected newborn infants followed prospectively from birth to 1 year of age. No food changes were required in 914 infants who were used as healthy controls. When CMPI was suspected (211 infants), diagnostic dietary interventions according to a standard protocol were performed. After exclusion of lactose intolerance, two positive cow's milk elimination/challenge tests were considered diagnostic of CMPI. Two hundred and eleven symptomatic infants were examined for possible CMPI. A large group of 80 infants improved on a lactose reduced formula. In 87/211 infants CMPI was excluded (sick controls). Finally CMPI was proven in 26 infants. The calculated incidence rate for CMPI was 2.8%. The principal symptoms in infants with CMPI were gastrointestinal, dermatological and respiratory in 50%, 31% and 19% respectively. A positive family history for atopy (first or second degree relatives) was more frequent in either CMPI infants (65%), or sick controls (63%) when compared to either healthy controls (35%) or infants improving on a low lactose formula (51%). Differences between patients with CMPI and sick controls were only found for the presence of atopy in at least 2 first degree relatives [(5/26 in CMPI infants and 4/87 in sick controls (P < 0.05)] and for multiorgan involvement [10/26 infants with CMPI as opposed to 12/87 in the sick control group (P < 0.02)]. These statistical differences are too weak to be of clinical value.

Humans↗

Effect of carbohydrate ingested on outcome in infants with mild gastroenteritis.

Children with mild acute gastroenteritis have not been observed for specific evidence of lactose intolerance yet are frequently fed a nonlactose formula. To determine whether such intervention is justified, 85 infants with mild acute gastroenteritis were followed prospectively. Infants were blindly and randomly assigned to 20 calorie/oz formula containing one of four carbohydrates: lactose, sucrose, polycose, or combined sucrose-polycose. Daily diaries were kept by parents, and patients were reexamined on days 2, 7, and 14 of the study. Evidence for rotavirus was detected in 23 infants, and five had bacterial pathogens. Symptoms resolved in most patients within 7 days, but five infants were subsequently hospitalized. Stool frequency, weight gain, and need for hospitalization did not differ significantly among the groups. Recovery from mild acute gastroenteritis occurred within 2 weeks irrespective of carbohydrate ingested.

Dietary Carbohydrates↗

[Yogurt as source of lactose autodigestion].

Microorganisms in yogurt have the capacity of quantitatively digest in vivo in the small intestine the lactose from yogurt. The process of autodigestion of lactose in yogurt reduces both lactose maldigestion and lactose intolerance in lactase deficient individuals. Enzyme activity in yogurt depends upon the buffer capacity of the yogurt, microbial cells resistance to acid and enzymatic activity and to the effect of bile in the microbial cell that release beta-galactosidase activity. Lactose autodigestion capacity of yogurt is significantly reduced in pasteurized yogurt and it is also affected by the type and amount of microorganism that is added to milk and by the presence of fat. Yogurt intake represents an important food alternative for lactase deficient individuals.

Digestion↗

Nutritional management of common gastrointestinal problems.

Nutritional management plays a vital role in many gastrointestinal problems commonly seen in primary care. Irritable bowel syndrome, lactose intolerance, and celiac sprue are three problems that are best managed by dietary changes. To achieve positive outcomes, NPs must know the latest nutritional interventions and provide their patients with counseling and education to support these dietary changes. Elements of high fiber, lactose-free, and gluten-free diets are discussed in this article.

Gastrointestinal Diseases↗