Self-reported Lactose Intolerance Research Articles

Self-Perceived Lactose Intolerance Versus Confirmed Lactose Intolerance in Irritable Bowel Syndrome: A Systematic Review.

Disorders of gut-brain interaction (DGBI) are prevalent, affecting 20-40% of the population, with irritable bowel syndrome (IBS) being the most common and impactful. While congenital lactose intolerance is rare, lactase deficiency in adults is widespread, causing gastrointestinal symptoms like bloating and diarrhea. Self-perceived lactose intolerance often overestimates symptoms, impacting dietary choices and quality of life, necessitating better understanding and management for improved patient outcomes. This article evaluates the diagnostic accuracy of self-reported lactose intolerance in patients with lactose intolerance and IBS through a systematic review. A systematic literature search was conducted using PubMed, EMBASE, and SCOPUS, including terms related to IBS, lactose intolerance, and self-reported symptoms, without applying filters to ensure comprehensive coverage. Inclusion criteria focused on observational studies with adult participants diagnosed with lactose intolerance, addressing symptoms and lactose malabsorption, while excluding non-English articles, reviews, editorials, and studies involving pediatric subjects. The systematic review analyzed six studies with 845 participants, revealing significant variability and moderate accuracy in self-reported lactose intolerance for diagnosing actual lactose intolerance in IBS patients. Hydrogen breath tests (HBTs) showed that self-reported symptoms often led to false positives, underscoring the need for objective diagnostic tools and standardized criteria. The findings highlight the complexity of diagnosing lactose intolerance in IBS patients and suggest that lactose-free diets and routine HBT should not be recommended without clear indications. The rigorous selection process ensured the inclusion of high-quality, relevant studies, thereby enhancing the reliability and validity of the review's findings. These studies revealed that a lactose-free diet should not be routinely recommended for IBS patients, nor should the routine use of HBT to identify lactose malabsorption in this group. Future research should focus on better understanding the factors influencing lactose perception and tolerance, which is crucial for more effective management of lactose intolerance in IBS patients.

Fecal Calprotectin in Self-Reported Milk Intolerance: Not Only Lactose Intolerance

The hypothesis is that inflammatory/allergic conditions should be considered in self-reported milk intolerance (SRMI) patients who test negative and/or are asymptomatic at Lactose Hydrogen Breath Test (LHBT). We analyzed fecal calprotectin (FCP) values in SRMI patients to investigate the frequency of a "positive" intestinal inflammation marker and its correlation with lactose tolerance/intolerance. Data from 329 SRMI patients were retrospectively analyzed; according to the positive/negative results (maldigester/digester) and the presence/absence of symptoms reported during LHBT (intolerant/tolerant), patients were divided into: 'lactose tolerants' (n. 104), 'maldigesters/intolerants' (n. 187), 'digesters/intolerants' (n. 38). FCP values were analyzed in all three subgroups. A percentage of SRMI patients complained of constipation (>15%), extraintestinal symptoms (>30% including anemia), multiple food hypersensitivity (7.6%) and had intraepithelial lymphocytic infiltration at duodenal biopsy (>50%). Over 50.0% showed FCP values above the normal limit. Lactose tolerants and maldigesters/intolerants had higher positivity frequencies (p < 0.0001, for both) and absolute values (p = 0.04, for maldigesters/intolerants) of FCP compared to digesters/intolerants. FCP was not useful to differentiate tolerant from intolerant subjects (AUC 0.58). Our data suggest the existence of an allergic/inflammatory pathogenetic mechanism in a subset of SRMI subjects. FCP results are in keeping with this hypothesis, even if they cannot differentiate lactose tolerant from intolerant patients.

The Perception of Lactose-Related Symptoms of Patients with Lactose Malabsorption.

Background: Dairy products are frequently considered responsible for post-prandial symptoms and are withdrawn from the diet, even against medical advice. We analysed the symptoms patients consider as lactose related; we also evaluated if psychological profile may affect the interpretation of the relationship between lactose and symptoms. Methods: In 268 patients undergoing lactose breath test, symptoms considered evoked by lactose intake were recorded and their severity measured. In the second part, symptom onset of 40 randomly selected patients was detected after both lactose and glucose breath test were blindly performed. Questionnaires evaluating anxiety, suggestibility and personality trait were administered. Key Results: Symptoms depending on functional gastrointestinal disorders or reflux disease were frequent in self-reported lactose-intolerant patients. In comparison with lactose malabsorption, these symptoms proved to be more frequent in patients with negative lactose breath test. The blinded administration of lactose and glucose demonstrated that a correct link between lactose intake and symptom onset was possible, only in 47.5% of the subjects, making this test inaccurate. None of the investigated psychological characteristics were different between patients with a nocebo response and patients not experiencing nocebo. Conclusions: Patients with self-reported lactose intolerance are frequently unaware about clinical presentation of this condition, and correct information is needed. The detection of symptom onset after lactose is an inaccurate test for lactose intolerance. Furthermore, the analysis of psychological characteristics of patients undergoing hydrogen breath test is not useful to select the subgroup at risk for a nocebo response. New strategies to diagnose lactose intolerance are mandatory.

Whole Cow's Milk but Not Lactose Can Induce Symptoms in Patients with Self-Reported Milk Intolerance: Evidence of Cow's Milk Sensitivity in Adults.

Background: Lactose intolerance is the most frequent food intolerance, but many subjects with self-reported milk intolerance (SRMI) are asymptomatic at lactose hydrogen breath test (LHBT). The aim of this study was to evaluate the frequency of lactose intolerance in SRMI patients and their clinical characteristics. Methods: In a retrospective study, the clinical records of 314 SRMI patients (259 females, mean age: 39.1 ± 13.5 years) were reviewed; 102 patients with irritable bowel syndrome (IBS) served as controls. In a prospective study, 42 SRMI patients, negatives at the LHBT, underwent a double-blind, placebo-controlled (DBPC) whole cow’s milk challenge. Results: In the retrospective study, only 178 patients (56%) were lactose maldigesters and intolerant at LHBT; 68% of the subjects with SRMI were suffering from IBS; 74% reported dyspepsia (p = 0.0001 vs. IBS controls); and weight loss was recorded in 62 SRMI patients (20%) (p = 0.01 vs. IBS controls). Duodenal histology showed intra-epithelial lymphocytosis in about 60% of cases. In the prospective study, 36 patients (86%) experienced symptoms during the DBPC cow’s milk challenge, and only 4 patients (9%) reacted to placebo (p = 0.0001). Conclusions: A percentage of SRMI patients were not suffering from lactose intolerance. DBPC revealed that SRMI patients had clinical reactions when exposed to whole cow’s milk.

Blinded Oral Challenges with Lactose and Placebo Accurately Diagnose Lactose Intolerance: A Real-Life Study.

Lactose intolerance (LI) is characterized by diarrhea, abdominal pain, or bloating occurring after lactose consumption in patients with lactose malabsorption. The National Institute of Health (NIH) proposed a double-blind placebo testing to identify LI individuals correctly. However, until now, no study used this approach in a real-life setting. We aimed to assess double-blind placebo challenge accuracy in diagnosing LI in patients with self-reported symptoms of LI. 148 patients with self-reported LI were consecutively enrolled and blindly underwent hydrogen breath test (HBT) after 25 g lactose or 1 g glucose (placebo) load. One week later, the subjects were challenged with the alternative substrate. Each subject completed a validated questionnaire, including five symptoms (diarrhea, abdominal pain, vomiting, bowel sounds, and bloating) scored on a 10-cm visual analog scale. Home questionnaire (HQ) referred to symptoms associated with the consumption of dairy products at home, while lactose questionnaire (LQ) and placebo questionnaire (PQ) referred to symptoms perceived throughout the 4-h after the administration of the substrates, respectively. After lactose load, HBT was positive in 81 patients (55%), of whom 60 (74%) reported relevant symptoms at LQ (lactose malabsorbers, LM). After placebo challenge, 45 out of 60 with a positive lactose challenge did not complain of symptoms and therefore were diagnosed as lactose intolerant, according to NIH definition. The blinded oral challenges with lactose and placebo accurately diagnose LI and identify patients who will likely benefit from a lactose-free diet.

Lactose Sensitivity and Lactose Malabsorption: The 2 Faces of Lactose Intolerance

Background/AimsSelf-reported lactose intolerance (LI) is frequent in patients with functional bowel disorders (FBD) that could be interpreted as irritable bowel syndrome (IBS). The present study aims to characterize the responses of patients with FBD, without small intestinal bacterial overgrowth (SIBO), and LI, in terms of lactose malabsorption (LM) and lactose sensitivity (LS) according to psychological and clinical features.MethodsOne hundred and fifty-eight consecutive FBD outpatients with LI, and no SIBO, were classified according to the Rome III questionnaire and filled Beck Depression Inventory, and State and Trait Anxiety questionnaires. They underwent a lactose tolerance test in which glycemia during 60 minutes and digestive symptoms for 3 hours were recorded.ResultsAbnormal lactose tolerance tests were found in 110 patients (70%), 44 (28%) with LM, 96 (61%) with LS, and 30 (19%) having both LM and LS. LM patients had a higher frequency of functional diarrhea (P = 0.040) and a lower frequency of dysphagia (P = 0.031). LS patients had a higher depression score (P = 0.007), higher frequency of globus (P = 0.042), irritable bowel syndrome (IBS) (P = 0.027) and mixed IBS (P = 0.049), and lower frequency of abdominal pain (P = 0.040). LS was significantly associated with a higher depression score (P = 0.002), and a higher frequency of globus (P = 0.046).ConclusionsThirty percent of LI patients have normal lactose absorption and normal LS. In the other 70% of patients, LI could be associated with LM and/or LS.

The Effect of Self-Reported Lactose Intolerance and Dairy Consumption on Bone Mineral Density Among American Hip Arthroplasty Patients: A Cross-Sectional Study.

The relationship between osteoporosis and lactose intolerance is unclear. This study aims to evaluate the association between self-reported lactose intolerance and symptom severity caused by lactose malabsorption and bone mineral density (BMD). A total of 496 American hip arthroplasty patients took part in this study. Information on BMD and socio-demographic factors were retrospectively extracted from medical records. BMD of the lumbar spine (LS), femoral neck of the operative hip (FNOH), and femoral neck of the non-operative hip (FNH) were measured via dual-energy x-ray absorptiometry scans (DXA). Patients also completed a survey regarding dietary and lifestyle habits from the time of surgery. We found that 9.3% of participants reported lactose intolerance and 33.3%% suffered from either osteopenia or osteoporosis in at least one (location). The population that did not self-identify as lactose intolerant consumed significantly more dairy (p < 0.0001) and animal protein (p = 0.004) than those with intolerance. There was no significant difference in BMD between self-identified lactose intolerant individuals and non-lactose intolerant individuals. In a stepwise multiple regression analysis, body mass index (BMI) and age were the only common predictors of BMD for all locations (p < 0.05). However, yogurt intake was a significant predictor of BMD of FNOH in the multivariate analysis. This study suggests that lactose intolerance is not associated with bone mineral density. We also found that being vegan or vegetarian may increase the risk of low BMD.

Adult lactose intolerance, calcium intake, bone metabolism and bone density in German-Turkish immigrants.

Adult lactose intolerance (ALI) significantly alters calcium intake and absorption, and thus may promote osteoporosis. ALI is a recessive condition with a geographical north-south gradient characterised by decreased levels of intestinal lactase. PCR-based genotyping of lactase (LCT) gene polymorphisms is a safe and easy way to diagnose ALI and may complement diagnostic procedures to identify individuals at risk for reduced calcium intake and subsequently osteoporosis due to lactose malabsorption. Therefore, we investigated the frequency of ALI and its influence on calcium intake, markers of bone metabolism and bone mineral density (BMD) in a cohort of Turkish immigrants living in Germany. We investigated single nucleotide polymorphisms of the LCT gene, calcium intake, markers of bone metabolism and BMD in 183 Turkish immigrants. ALI was diagnosed in 154 out of 183 (81%) probands. ALI was significantly associated with self-reported lactose intolerance (p < 0.001) and dislike for dairy products (p < 0.01). Osteopenia was diagnosed in 59 out of 183 (32%) and osteoporosis in 15 out of 183 (8%) probands. Probands with reduced BMD had ALI in 86%. All probands had a decreased calcium intake [mg/week]. There was no significant association between ALI, calcium intake, markers of bone metabolism or BMD. Turkish immigrants mostly have ALI and overall show a reduced calcium intake per week. However, ALI did not significantly influence calcium intake, markers of bone metabolism or BMD in this cohort. Therefore, ALI in Turkish immigrants does not seem to be a risk factor for osteoporosis.

Prevalence of lactose intolerance in patients with diarrhea-predominant irritable bowel syndrome: data from a tertiary center in southern China

BackgroundSymptoms associated with lactose intolerance (LI) and diarrhea-predominant irritable bowel syndrome (IBS-D) are almost the same. These disease entities are difficult to differentiate clinically. In practice, differential diagnosis depends on self-reported patient milk intolerance. However, there is limited data on the prevalence of LI in China. The aim of this study was to investigate the prevalence of LI in IBS-D patients and asymptomatic healthy controls.MethodsLactose malabsorption (LM) was diagnosed by a lactose hydrogen breath test (HBT) and was defined by peak breath H2 excretion over the baseline level of ≥ 20 ppm. LI-related symptoms were monitored for 8 h following lactose administration. LI was defined in LM patients with positive symptoms during the observation time. Patients with IBS-D were additionally asked if they were intolerant to milk.ResultsA total of 109 eligible IBS-D patients (Rome III criteria) and 50 healthy controls were enrolled in this study. Except for hydrogen non-producers, the prevalence of LM did not differ between IBS-D patients and the control group (85%, 82/96 vs 72%, 34/47; P = 0.061). There was, however, a higher LI prevalence in IBS patients than in healthy subjects (45%, 43/96 vs 17%, 8/47; P = 0.002). Sensitivity, specificity, and positive and negative predictive values of self-reported milk intolerance for detecting LI were 58, 58, 53, and 63%, respectively.ConclusionsPrevalence of LI is significantly higher in IBS-D patients than in healthy subjects. Self-reported milk intolerance is a poor diagnostic predictor of LI.

Perception of lactose intolerance impairs health-related quality of life.

Chronic conditions impair perception of well-being. Malabsorption of lactose is the most frequent form of malabsorption and manifests as lactose intolerance. There is a lack of information regarding their impact on self-perception of health. The objective of this study is to determine the subjective impact of self-reported lactose intolerance or objective lactose malabsorption on patient health by using a patient-reported outcome to measure health-related quality of life (HRQOL) and modification of lactose-containing food diet. A 3-year prospective, cross-sectional study was performed in patients referred for a lactose hydrogen breath test. Patients were asked about their subjective opinion relative to their lactose tolerance and completed a validated, specific questionnaire to determine symptoms of intolerance during habitual consumption of dairy. A 50-g lactose breath test was then performed. Patients were grouped as absorbers vs malabsorbers and tolerant vs intolerants. A total of 580 patients were included (median age 30 years, 419 female). Overall, 324 patients (56%) considered themselves lactose intolerant and that perception was associated with avoidance of dairy consumption (55% vs only 9% of self-defined tolerants). Self-perception of intolerance was associated with lower HRQOL scores (median, 60 vs 70, P<0.01). In contrast, lactose objective malabsorption was not clearly associated with dairy avoidance (41% of malabsorbers avoided dairy vs 31% of absorbers). However, HRQOL scores were also significantly lower in malabsorbers than in absorbers (60 vs 70 respectively, P<0.001). Subjective perception of lactose intolerance affects the decision to avoid dairy even more than objective malabsorption. However, both self-perception of lactose intolerance and objective lactose malabsorption are associated with poorer perceived quality of life.

Nodular lymphoid hyperplasia: A marker of low-grade inflammation in irritable bowel syndrome?

AIMTo evaluate the prevalence of nodular lymphoid hyperplasia (NLH) in adult patients undergoing colonoscopy and its association with known diseases.METHODSWe selected all cases showing NLH at colonoscopy in a three-year timeframe, and stratified them into symptomatic patients with irritable bowel syndrome (IBS)-type symptoms or suspected inflammatory bowel disease (IBD), and asymptomatic individuals undergoing endoscopy for colorectal cancer screening. Data collection included medical history and final diagnosis. As controls, we considered all colonoscopies performed for the aforementioned indications during the same period.RESULTSOne thousand and one hundred fifty colonoscopies were selected. NLH was rare in asymptomatic individuals (only 3%), while it was significantly more prevalent in symptomatic cases (32%). Among organic conditions associated with NLH, the most frequent was IBD, followed by infections and diverticular disease. Interestingly, 31% of IBS patients presented diffuse colonic NLH. NLH cases shared some distinctive clinical features among IBS patients: they were younger, more often female, and had a higher frequency of abdominal pain, bloating, diarrhoea, unspecific inflammation, self-reported lactose intolerance and metal contact dermatitis.CONCLUSIONAbout 1/3 of patients with IBS-type symptoms or suspected IBD presented diffuse colonic NLH, which could be a marker of low-grade inflammation in a conspicuous subset of IBS patients.

Self-reported lactose intolerance in clinic patients with functional gastrointestinal symptoms: prevalence, risk factors, and impact on food choices.

Many patients complain of abdominal symptoms with dairy products; however, clinical and psychosocial factors associated with self-reported lactose intolerance (SLI) have not been assessed in large studies. In particular, data are lacking from lactase deficient populations. This prospective cohort study assessed the prevalence of, and risk factors for, SLI in Chinese patients attending a gastroenterology clinic. Consecutive patients completed questionnaires to assess digestive health (Rome III), psychological state (HADS), life event stress (LES), food intake, and quality-of-life (SF-8). A representative sample completed genetic studies and hydrogen breath testing (HBT) at the clinically relevant dose of 20 g lactose. SLI was present in 411/910 (45%) clinic patients with functional abdominal symptoms. The genotype in all subjects was C/C-13910. A small number of novel SNPs in lactase promoter region were identified, including C/T-13908 which appeared to confer lactase persistence. Over half of the patients (54%) completed the 20 g lactose HBT with 58% (285/492) reporting typical symptoms. Positive and negative predictive values of SLI for abdominal symptoms during HBT were 60% and 44%, respectively. Psychological state and stress were not associated with SLI in clinic patients. SLI impacted on physical quality-of-life and was associated with reduced ingestion of dairy products, legumes, and dried fruit (p ≤ 0.05). In a lactase deficient population, approximately half of patients attending clinic with functional gastrointestinal symptoms reported intolerance to dairy products; however, SLI did not predict findings on 20 g lactose HBT. Independent of psychosocial factors, SLI impacted on quality-of-life and impacted on food choices with restrictions not limited to dairy products.

Mo1304 The Effect of YH12852, Novel 5-HT4 Partial Agonist, on Postoperative Ileus in Guinea Pig

Background: Functional bowel disorders (FBDs) are common, impact on quality of life and are associated with significant healthcare costs. The occurrence of FBD symptoms has been linked to dietary intolerance; however the interaction between dietary, demographic, and psychosocial factors has not been assessed in adequately powered, population-based studies. Aims: To investigate the prevalence of FBDs in an Chinese population with lactase deficiency and the contribution of food intolerance (self-reported lactose intolerance (SLI) and lactose intake), psychological factors and stressful life events on FBDs. Methods: Adult subjects (16-74 years) selected at random from the community completed questionnaires detailing demographic information, gastrointestinal symptoms, consumption of lactose, psychological factors, life event stress and quality of life. FBDs were diagnosed by Rome III criteria. A logistic regression model was used to identify independent risk factors that increased the likelihood of subjects reporting FBD symptoms.Results: Complete responses were available from 1999/2115 (94.5%) subjects. 831 (41.6%) reported FBD symptoms. Among them the unspecified functional bowel disorder was the most prevalent (12.6%). The second was functional constipation (FC) (9.9%), the followed by functional bloating (FB)(6.8%),functional diarrhea(FD)(6.5%) and IBS (5.9%). More women than men had functional constipation (6.2% vs. 3.8%, p<0.001) and bloating (4.0% vs. 2.8%, p=0.038) but this was not found for functional diarrhea (3.0% vs. 3.5%) or irritable bowel syndrome (2.9% vs. 3.0%). FBDs reported food intolerance and specifically SLI more often than non-FBDs (28.8% vs. 16.0%, p<0.001) and consumed less lactose (p=0.019). FBD patients had a greater likelihood of depression or anxiety than non-FBDs (both, p<0.001), experienced more Life Event stress than non-FBDs (p<0.001) and reported lower quality of life (p<0.001). The joint effects of psychiatric morbidity, life event stress and lactose intake on the risk of FBDs are observed. In a logistic regression model, independent risk factors for FBDs included SLI (OR 1.81 (95%CI 1.44-2.27, p<0.001)), psychological illness (OR 1.46 (95% CI 1.19-1.81, p<0.001)) and recent life event stress (OR 1.28 (95%CI 1.06-1.55, p=0.009)). Conclusions: FBDs are common in China. Food intolerance, psychological factors and life event stress increase the likelihood of subjects in the general population reporting FBD symptoms. Table 1. The joint association of psychologic disease, life event stress, lactose intake with FBD among subjects.

Mo1303 Inflammation and Impaired Motility in Postoperative Ileus

Background: Functional bowel disorders (FBDs) are common, impact on quality of life and are associated with significant healthcare costs. The occurrence of FBD symptoms has been linked to dietary intolerance; however the interaction between dietary, demographic, and psychosocial factors has not been assessed in adequately powered, population-based studies. Aims: To investigate the prevalence of FBDs in an Chinese population with lactase deficiency and the contribution of food intolerance (self-reported lactose intolerance (SLI) and lactose intake), psychological factors and stressful life events on FBDs. Methods: Adult subjects (16-74 years) selected at random from the community completed questionnaires detailing demographic information, gastrointestinal symptoms, consumption of lactose, psychological factors, life event stress and quality of life. FBDs were diagnosed by Rome III criteria. A logistic regression model was used to identify independent risk factors that increased the likelihood of subjects reporting FBD symptoms.Results: Complete responses were available from 1999/2115 (94.5%) subjects. 831 (41.6%) reported FBD symptoms. Among them the unspecified functional bowel disorder was the most prevalent (12.6%). The second was functional constipation (FC) (9.9%), the followed by functional bloating (FB)(6.8%),functional diarrhea(FD)(6.5%) and IBS (5.9%). More women than men had functional constipation (6.2% vs. 3.8%, p<0.001) and bloating (4.0% vs. 2.8%, p=0.038) but this was not found for functional diarrhea (3.0% vs. 3.5%) or irritable bowel syndrome (2.9% vs. 3.0%). FBDs reported food intolerance and specifically SLI more often than non-FBDs (28.8% vs. 16.0%, p<0.001) and consumed less lactose (p=0.019). FBD patients had a greater likelihood of depression or anxiety than non-FBDs (both, p<0.001), experienced more Life Event stress than non-FBDs (p<0.001) and reported lower quality of life (p<0.001). The joint effects of psychiatric morbidity, life event stress and lactose intake on the risk of FBDs are observed. In a logistic regression model, independent risk factors for FBDs included SLI (OR 1.81 (95%CI 1.44-2.27, p<0.001)), psychological illness (OR 1.46 (95% CI 1.19-1.81, p<0.001)) and recent life event stress (OR 1.28 (95%CI 1.06-1.55, p=0.009)). Conclusions: FBDs are common in China. Food intolerance, psychological factors and life event stress increase the likelihood of subjects in the general population reporting FBD symptoms. Table 1. The joint association of psychologic disease, life event stress, lactose intake with FBD among subjects.

Effect of Raw Milk on Lactose Intolerance: A Randomized Controlled Pilot Study

This pilot study aimed to determine whether raw milk reduces lactose malabsorption and/or lactose intolerance symptoms relative to pasteurized milk. We performed a crossover trial involving 16 adults with self-reported lactose intolerance and lactose malabsorption confirmed by hydrogen (H2) breath testing. Participants underwent 3, 8-day milk phases (raw vs 2 controls: pasteurized, soy) in randomized order separated by 1-week washout periods. On days 1 and 8 of each phase, milk consumption was 473 mL (16 oz); on days 2 to 7, milk dosage increased daily by 118 mL (4 oz), beginning with 118 mL (4 oz) on day 2 and reaching 710 mL (24 oz) on day 7. Outcomes were area under the breath H2 curve (AUC H2) and self-reported symptom severity (visual analog scales: flatulence/gas, audible bowel sounds, abdominal cramping, diarrhea). AUC H2 (mean ± standard error of the mean) was higher for raw vs pasteurized on day 1 (113 ± 21 vs 71 ± 12 ppm·min·10(-2), respectively, P = .01) but not day 8 (72 ± 14 vs 74 ± 15 ppm·min·10(-2), respectively, P = .9). Symptom severities were not different for raw vs pasteurized on day 7 with the highest dosage (P >.7). AUC H2 and symptom severities were higher for both dairy milks compared with soy milk. Raw milk failed to reduce lactose malabsorption or lactose intolerance symptoms compared with pasteurized milk among adults positive for lactose malabsorption. These results do not support widespread anecdotal claims that raw milk reduces the symptoms of lactose intolerance.

Dietary calcium intake in patients with inflammatory bowel disease

Background & aimsOsteopenia and increased risk for fractures in IBD result from several factors. Aim of the studyTo investigate the dietary intake of calcium in IBD patients. MethodsA 22-item quantitative validated frequency food questionnaire was used for quantifying dietary calcium in relation to gender and age, in 187 IBD patients, 420 normal- and 276 diseased controls. Statistical analysisMann–Whitney, chi-square- and T-tests. ResultsThe mean calcium intake was 991.0±536.0 (105.8% Recommended Daily Allowances) and 867.6±562.7SDmg/day (93.8% RDA) in healthy and diseased controls, and 837.8±482.0SDmg/day (92.7% RDA) in IBD, P<0.001. Calcium intake was high in celiac disease (1165.7±798.8SDmg/day, 120% RDA), and non-significantly lower in ulcerative colitis than in Crohn's disease (798.7±544.1SDmg/day vs 881.9±433.0). CD and UC females, but not males, had a mean calcium intake well under RDA. In all study groups the intake was lower in patients believing that consumption of lactose-containing food induced symptoms, versus those who did not (105.8% vs 114.3% RDA in normal controls; 100.4% vs 87.6% RDA in IBD). ConclusionsDiet in IBD patients contained significantly less calcium than in healthy controls. Gender and age, more than diagnosis, are central in determining inadequate calcium intake, more so in IBD. Self-reported lactose intolerance, leading to dietary restrictions, is the single major determinant of low calcium intake. Inadequate calcium intake is present in one third of IBD patients and represents a reversible risk factor for osteoporosis, suggesting the need for tailored nutritional advice in IBD.

Self-perceived lactose intolerance and lactose breath test in elderly

BackgroundLactose maldigestion is quite common at all ages. Lactose maldigestion is also common in the elderly but information relative to their symptoms is scarce.Purpose To determine whether in the elderly self-reported lactose intolerance in the normal home setting is comparable to symptoms provoked by a controlled lactose challenge.Design Observational, prospective and transverse study performed in patients referred for a lactose H2 breath test. Material and methodsPatients first completed a validated questionnaire inquiring about symptoms associated with usual consumption of dairy products at home (“home symptoms”). After a 50-g lactose breath test, symptoms score was also obtained. Patients were grouped as absorbers versus malabsorbers (according to the lactose test result) and younger or older than 65years old. ResultsSix hundred and one patients have been included (89 older than 65years old and 512 younger than 65years). Prevalence of lactose maldigestion was the same in both age groups (50% vs 51%). In lactose maldigesters, orocecal transit time and hydrogen excretion capacity after lactose load were independent of age. Oral lactose load induces symptoms in lactose maldigesters. Lactose-induced intolerance symptoms were less intense in elderly than in younger adults (symptoms score of 8 vs 19, P<0.001). Home symptoms were not related to lactose digestion capacity. ConclusionsIn the elderly, lactose maldigestion is associated with increased excretion of hydrogen after oral 50g lactose load but symptoms are less marked than in younger adults. Self-reported intolerance symptoms at home are not clearly related to lactose maldigestion in elderly.

Lactose malabsorption and intolerance: pathogenesis, diagnosis and treatment.

Lactose malabsorption is a common condition caused by reduced expression or activity of lactase in the small intestine. In such patients, lactose intolerance is characterized by abdominal symptoms (e.g. nausea, bloating, and pain) after ingestion of dairy products. The genetic basis of lactose malabsorption is established and several tests for this condition are available, including genetic, endoscopic, and H2-breath tests. In contrast, lactose intolerance is less well understood. Recent studies show that the risk of symptoms after lactose ingestion depends on the dose of lactose, lactase expression, intestinal flora, and sensitivity of the gastrointestinal tract. Lactose intolerance has recently been defined as symptoms developing after ingestion of lactose which do not develop after placebo challenge in a person with lactose maldigestion. Such blinded testing might be especially important in those with functional gastrointestinal diseases in whom self-reported lactose intolerance is common. However, placebo-controlled testing is not part of current clinical practice. Updated protocols and high-quality outcome studies are needed. Treatment options of lactose intolerance include lactose-reduced diet and enzyme replacement. Documenting the response to multiple doses can guide rational dietary management; however, the clinical utility of this strategy has not been tested. This review summarizes the genetic basis, diagnosis, and treatment of lactose malabsorption and intolerance.

Perceived lactose intolerance in adult Canadians: a national survey

Although double-blind studies show that lactose-intolerant individuals can consume moderate quantities of milk products without perceptible symptoms, many who perceive that they are lactose intolerant limit or avoid milk products, potentially compromising calcium and vitamin D intakes. Adult Canadians are at risk of inadequate intakes of these nutrients, but no data exist on the prevalence, correlates, and potential impact of perceived lactose intolerance among Canadians. To address this, a Web-based survey of a population-representative sample of 2251 Canadians aged ≥19 years was conducted. Overall, 16% self-reported lactose intolerance. This was more common in women (odds ratio (OR), 1.84; 95% CI, 1.46-2.33) and in nonwhites (OR, 1.79; 95% CI, 1.24-2.58) and less common in those >50 years of age (OR, 0.71; 95% CI, 0.56-0.90) and in those completing the survey in French (OR, 0.74; 95% CI, 0.56-0.99). Those with self-reported lactose intolerance had lower covariate-adjusted milk product and alternative intakes (mean ± SE; 1.40 ± 0.08 servings·day(-1) vs. 2.33 ± 0.03 servings·day(-1), p < 0.001). A greater proportion used supplements containing calcium (52% vs. 37%, p < 0.001) and vitamin D (58% vs. 46%, p < 0.001), but calcium intakes from the combination of milk products, alternatives, and supplements were lower (739 ± 30 mg·day(-1) vs. 893 ± 13 mg·day(-1), p < 0.0001). Variation in self-reported lactose intolerance by sex, age, and language preference was unexpected and suggests that some groups may be more vulnerable to the perception that they are lactose intolerant. Regardless of whether lactose intolerance is physiologically based or perceptual, education is required to ensure that calcium intakes are not compromised.

P577 Cost-effectiveness of episodic or maintenance infliximab versus standard treatment in an incidence cohort of Crohn's disease patients with 10-years follow-up

in all study groups (105.8% vs 114.3% RDA in normal controls; 88.7% vs 109.2% RDA in diseased controls, 100.4% vs 87.6% RDA in IBD. Conclusions: In this study IBD patients had a significantly lower Ca intake than healthy controls. In accordance to previous studies, gender and age, more than diagnosis, are relevant factors in determining inadequate Ca intake. The trend is more marked in IBD, especially in postmenopausal women. Selfreported lactose intolerance, leading to dietary restrictions, is the single major determinant of low Ca intake in all pts groups, irrespective to diagnosis, age and gender. Inadequate Ca intake is observed in about one third of IBD pts and represents an easily reversible risk factor for osteoporosis. The observation that celiac patients on low gluten diet have a Ca intake well over RDA, further supports the need for tailored nutrition advice also in ulcerative colitis and Crohn’s disease.