Lactose malabsorption and intolerance in older adults.

PURPOSE OF REVIEW: Lactose malabsorption and intolerance are very common conditions. However, their optimal approach, including the diagnostic assessment, remains a matter of debate, especially in advanced age. In this brief review, we focused on current knowledge, concerns, and impact in clinical practice of lactose malabsorption and intolerance in elderly. RECENT FINDINGS: Older adults are at high risk of malnutrition, owing to frequent occurrence of cognitive impairment, loss of appetite, dysphagia, and poor oral health. A significant decrease in the consumption of dairy products may lead to inadequate intake of high-quality protein and minerals, with a consequent impact on muscle and bone health. Testing for lactose malabsorption may be challenging in older adults, if not useless. Instead, a detailed clinical evaluation should always be pursued to identify both lactose intolerance and all confounding factors mimicking the same clinical picture. SUMMARY: The management of lactose malabsorption and intolerance in older adults deserves a personalized approach. Because of the importance of maintaining an adequate nutritional status in this age group, efforts should be put forth to avoid excessively restrictive diets.

Lactose intolerance and levothyroxine malabsorption: a review of the literature and report of a series of patients treated with liquid L-T4 without lactose.

In hypothyroid patients needing large doses of levothyroxine (L-T4) (>1.7-2 µg/kg/day) to reach euthyroidism, lactose intolerance (LI) needs to be excluded, owing to the high prevalence in the population. If LI is present, a lactose-free diet decreases the rate of L-T4 malabsorption. However, an increased requirement of L-T4 is described in patients with LI, which can be beneficially treated using lactose-free L-T4 formulation. The lactose-free liquid L-T4 formulation is able to circumvent LI malabsorption leading to the normalization of thyroid-stimulating hormone (TSH) in patients with subclinical hypothyroidism and long-term stable TSH levels.

Prebiotic Strategies to Manage Lactose Intolerance Symptoms.

Lactose intolerance, which affects about 65-75% of the world's population, is caused by a genetic post-weaning deficiency of lactase, the enzyme required to digest the milk sugar lactose, called lactase non-persistence. Symptoms of lactose intolerance include abdominal pain, bloating and diarrhea. Genetic variations, namely lactase persistence, allow some individuals to metabolize lactose effectively post-weaning, a trait thought to be an evolutionary adaptation to dairy consumption. Although lactase non-persistence cannot be altered by diet, prebiotic strategies, including the consumption of galactooligosaccharides (GOSs) and possibly low levels of lactose itself, may shift the microbiome and mitigate symptoms of lactose consumption. This review discusses the etiology of lactose intolerance and the efficacy of prebiotic approaches like GOSs and low-dose lactose in symptom management.

The Adult Carbohydrate Perception Questionnaire Identifies Patients with Lactose or Fructose Intolerance Who Respond to Diet.

INTRODUCTION: There is no evidence that a positive breath test is a good predictor of the success of a carbohydrate-restricted diet. Our objective was to investigate whether patients in whom lactose intolerance (LIT) or fructose intolerance (FIT) is diagnosed by validated symptom measurement respond to diet. METHODS: Patients referred for evaluation of LIT or FIT underwent hydrogen/methane breath testing (malabsorption test) and symptom measurement with the adult Carbohydrate Perception Questionnaire (aCPQ, intolerance test) before and after 50 g lactose or 25 g fructose. Patients with a positive aCPQ received instructions on specific diets and supplements. Severity of abdominal pain, bloating, diarrhoea, flatulence, and nausea were measured using a visual analogue scale (VAS) before (VAS1, mm) and after (VAS2, mm) diet. The change in VAS for individual symptoms and overall symptoms after diet is expressed as deltaVAS (mm) and as change relative to VAS1 (%). RESULTS: Forty-one patients were included (23 LIT, 8 FIT, 10 LIT+FIT). Eight patients had negative breath tests (no malabsorption). After 2 months of diet, the overall VAS and the individual symptoms decreased (p < 0.001). Overall VAS1 and the VAS1 for individual symptoms correlated significantly with the decrease in deltaVAS (mm) after diet. Nineteen patients (46%) had total recovery, and additional 13 patients (32%) had improvement of >50%. Response to diet was independent of breath test results. CONCLUSION: This uncontrolled and unblinded study suggests that patients with carbohydrate intolerance diagnosed by aCPQ benefit significantly from diet, independent of the presence of malabsorption. Controlled studies are required to confirm these results in larger patient groups.

Added Value of 13C Analysis in Breath Tests in H2-Negative Subjects to Diagnose Lactose Malabsorption: A Proof of Concept Study.

INTRODUCTION: Diagnosing lactose malabsorption is usually based on hydrogen excretion in breath after a lactose challenge. However, a proportion of subjects with lactose malabsorption will not present a rise in hydrogen. Measuring excretion of methane or stable isotope labeled 13CO2 after ingestion of 13C-lactose has been proposed to mitigate this problem. OBJECTIVE: The aim of the study was to assess the performance of measuring methane and 13CO2 in individuals with normal hydrogen excretion compared to a genetic lactase non-persistence test. METHODS: Individuals referred for lactose breath testing and healthy controls were included. Participants received 13C-enriched lactose, performed breath testing, and underwent genotyping for a marker of lactase non-persistence (13910C*T). Using genotype as gold standard, the performance of measuring methane and 13CO2 excretion was assessed. RESULTS: 151 subjects participated in the study, 50 of which presented a lactase non-persistent genotype. Of these, 72% were correctly diagnosed through hydrogen excretion of ≥ 20 ppm above baseline. In subjects with normal hydrogen excretion, cumulative 13C excretion had an area under the curve (AUC) of the receiver operating characteristics (ROC) curve of 0.852. Sensitivity was 93% and specificity was 51% for the current cutoff of 14.5%. The optimal cutoff was 12.65% (sensitivity 93%, specificity 70%). The ROC curve of peak methane had an AUC of 0.542 (sensitivity of 14%, specificity of 91% for cutoff ≥ 10 ppm). CONCLUSIONS: In individuals with genetically demonstrated lactase non-persistence and negative hydrogen breath test, the use of 13C-lactose with measurement of 13CO2 excretion and hydrogen is a well-performing test to detect the lactose malabsorption and performs better than methane in our cohort.

EVALUATION OF AGREEMENT BETWEEN C/T-13910 POLYMORPHISM GENOTYPING RESULTS AND LACTOSE TOLERANCE TEST RESULTS: A RETROSPECTIVE POPULATION-BASED STUDY IN BRAZIL.

BACKGROUND: Lactose tolerant test (LTT) is the most broadly used diagnostic test for lactose intolerance in Brazil, is an indirect, minimally invasive and a low-cost test that is widely available in primary care and useful in clinical practice. The C/T-13910 polymorphism in lactase persistence has been well characterized in Caucasian populations, but there are no studies evaluating the concordance between C/T-13910 polymorphism genotyping results and LTT results in Brazil, where the population is highly mixed. OBJECTIVE: We aimed to evaluate agreement between presence of C/T-13910 polymorphism genotyping and malabsorption in LTT results. METHODS: This is a retrospective analysis of a Brazilian population whose data were collected from a single laboratory database present in several Brazilian states. Results of individuals who underwent both genetic testing for lactose intolerance (C/T-13910 polymorphism genotyping) and an LTT from April 2016 until February 2019 were analysed to evaluate agreement between tests. Groups were classified according to age (<10-year-old (yo), 10-17 yo, ≥18 yo groups) and state of residence (São Paulo or Rio Grande do Sul). Results: Among the 404 patients evaluated, there was agreement between the genotyping and LTT results in 325 (80.4%) patients and discordance in 79 (19.6%) patients (k=0.42 -moderate agreement). Regarding the genotype, 47 patients with genotype C/C (lactase nonpersistence) had normal LTT results, and 32 with genotype C/T or T/T (indicating lactase persistence) had abnormal LTT results. Neither age nor state of residence (Rio Grande do Sul or São Paulo) affected the agreement between test results. CONCLUSION: Considering the moderate agreement between C/T-13910 polymorphism genotyping and LTT results (κ=0.42) in the Brazilian population, we hypothesize that an analysis of other polymorphisms could be a strategy to improve the agreement between genotyping and established tests and suggest that additional studies should focus on exploring this approach. BACKGROUND: • Lactose intolerance is highly prevalent and may be implicated as a cofactor, or as a differential diagnosis, in many gastrointestinal conditions. BACKGROUND: • The C/T-13910 polymorphism in lactase persistence is well characterized in Caucasian populations for lactase persistence. BACKGROUND: • Concordance between genotyping and functional tests does not occur in all patients. BACKGROUND: • Brazil has a highly mixed population and knowledge regarding presence of other polymorphisms is of importance in clarifying difficult cases.

A review of dairy food intake for improving health among black adults in the US.

The adult life stage encompasses a range of new experiences, opportunities, and responsibilities that impact health and well-being. During this life stage, health disparities continue to increase for Black Americans, with Black adults having a disproportionate burden of obesity, chronic diseases, comorbidities, and worse treatment outcomes compared to their White peers. While many of the underlying factors for these disparities can be linked to longstanding sociopolitical factors such as systemic racism, food insecurity, and poor access to healthcare, there are also several modifiable risk factors that are known to significantly impact health outcomes, such as improving diet quality, increasing physical activity, and not smoking. Of all the modifiable risk factors known to impact health, improving dietary habits is the factor most consistently associated with better outcomes for body weight and chronic disease. Of the major food groups recommended by the 2020-2025 Dietary Guidelines for Americans (DGA) for achieving healthier dietary patterns, dairy foods have a nutrient profile which matches most closely to what Black Americans are inadequately consuming (e.g., vitamin A, vitamin D, calcium, magnesium). However, Black adults tend to consume less than half the recommended daily servings of dairy foods, in part, due to issues with lactose intolerance, making higher intake of dairy foods an ideal target for improving diet quality and health in this population. This review examines the current body of evidence exploring the links between dairy intake, obesity, cardiometabolic disease risk, chronic kidney disease, and the most common types of cancer, with a special focus on health and disparities among Black adults. Overall, the evidence from most systematic reviews and/or meta-analyses published in the last decade on dairy intake and health outcomes has been conducted on White populations and largely excluded research on Black populations. The findings from this extensive body of research indicate that when teamed with an energy-restricted diet, meeting or exceeding the DGA recommended 3 daily servings of dairy foods is associated with better body weight and composition outcomes and lower rates of most common chronic diseases than lower intake (<2 servings per day). In addition to the number of daily servings consumed, the specific types (e.g., milk, yogurt, cheese) and subtypes (e.g., low-fat, fermented, fortified) consumed have also been shown to play major roles in how these foods impact health. For example, higher intake of fermented dairy foods (e.g., yogurt) and vitamin D fortified dairy products appear to have the most protective effects for reducing chronic disease risk. Along with lactose-free milk and cheese, yogurt is also generally low in lactose, making it an excellent option for individuals with lactose intolerance, who are trying to meet the DGA recommendations for dairy food intake.

Lactose Intolerance versus Cow's Milk Allergy in Infants: A Clinical Dilemma.

Due to its very early introduction, cow's milk is one of the first foods that can cause adverse reactions in human beings. Lactose intolerance (LI) and cow's milk allergy (CMA) are the most common adverse reactions to cow's milk. While LI is due to insufficient small intestinal lactase activity and/or a large quantity of ingested lactose, CMA is an aberrant immune reaction to cow's milk proteins, particularly casein or ß-lactoglobulin. However, the clinical manifestations of LI and CMA, particularly their gastrointestinal signs and symptoms, are very similar, which might lead to misdiagnosis or delayed diagnosis as well as nutritional risks due to inappropriate dietary interventions or unnecessary dietary restriction. Formula-fed infants with LI should be treated with formula with reduced or no lactose, while those with CMA should be treated with formula containing extensive hydrolyzed cow's milk protein or amino acids. This review is therefore written to assist clinicians to better understand the pathophysiologies of LI and CMA as well as to recognize the similarities and differences between clinical manifestations of LI and CMA.

Executive summary: The role of dairy food intake for improving health among Black Americans across the life continuum.

Given the complex relationships that many Black individuals have with dairy foods, due to issues with lactose intolerance or other cultural factors, the National Medical Association has made considerable efforts to examine the role that dairy foods play in the health and well-being of Black Americans. Over the last two decades, the National Medical Association and its partners have produced multiple reports on the value of including adequate milk and dairy foods in the diets of Black Americans. These publications have highlighted the impact that inadequate consumption of dairy foods and nutrients have on chronic disease risks. Past publications have also provided evidence-based recommendations for the proper diagnosis and management of lactose intolerance. This new series of evidence reviews focuses on dairy's role in improving nutrition and health among Black Americans across the life course and covers an extensive amount of new research that highlights additional health disparities and provides further evidence-based strategies for the management of lactose intolerance. Much like the 2020-2025 Dietary Guidelines for Americans, this work utilizes a life course approach to better address dairy intake on health outcomes for different ages and life stages: 1) pregnancy, fetal development, and lactation, 2) infants, toddlers, and young children, 3) older children and adolescents, 4) adults, and 5) geriatric populations. Overall, the findings and conclusions from this series of evidence reviews continue to indicate that higher dairy intake is associated with reduced risk for many of the most commonly occurring deficiencies and diseases impacting each life stage, and that Black Americans would receive significantly greater health benefits by increasing their daily dairy intake levels to meet the national dietary recommendations than they would from continuing to fall short of these recommendations. However, these recommendations must be considered with appropriate context and nuance as the intake of different dairy products can have different impacts on health outcomes. For instance, vitamin D fortified dairy products and fermented dairy products like yogurt - which are low in lactose and rich in live and active cultures - tend to show the greatest impacts for reducing disease risk across the life continuum, while whole-fat dairy foods may be most beneficial in early life for optimal brain development, and more protein-rich options may be most beneficial in later life to help maintain muscle mass and function.

Evaluation of a novel stationary phase for the separation of lactose and isomers in lactose-free products using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD).

Lactose intolerance is a widespread condition, which prevents a large number of people from consuming dairy products as a part of their daily diet. It is estimated that an average of 65% of the global population is suffering from lactose intolerance. The global market for 'lactose-free' dairy products is rapidly growing and the criteria for 'lactose-free' labelled products are becoming stricter. To check the lactose contents in these products there is a need for fast, sensitive, and selective analytical method. A method is presented for fast and sensitive determination of lactose and its isomers using High-Performance Anion Exchange Chromatography in combination with Pulsed Amperometric Detection (HPAEC-PAD). The use of a new anion-exchange column, SweetSep™ AEX200, which is a strong anion-exchange column with highly monodisperse 5 µm particles, allowed the separation of all compounds of interest in less than 8 min with high resolution. A variety of dairy products were analyzed to demonstrate the versatility of the method.

Cow's Milk: A Benefit for Human Health? Omics Tools and Precision Nutrition for Lactose Intolerance Management.

Cow's milk (CM) is a healthy food consumed worldwide by individuals of all ages. Unfortunately, "lactase-deficient" individuals cannot digest milk's main carbohydrate, lactose, depriving themselves of highly beneficial milk proteins like casein, lactoalbumin, and lactoglobulin due to lactose intolerance (LI), while other individuals develop allergies specifically against these proteins (CMPA). The management of these conditions differs, and an inappropriate diagnosis or treatment may have significant implications for the patients, especially if they are infants or very young children, resulting in unnecessary dietary restrictions or avoidable adverse reactions. Omics technologies play a pivotal role in elucidating the intricate interactions between nutrients and the human body, spanning from genetic factors to the microbiota profile and metabolites. This comprehensive approach enables the precise delineation and identification of distinct cohorts of individuals with specific dietary requirements, so that tailored nutrition strategies can be developed. This is what is called personalized nutrition or precision nutrition (PN), the area of nutrition that focuses on the effects of nutrients on the genome, proteome, and metabolome, promoting well-being and health, preventing diseases, reducing chronic disease incidence, and increasing life expectancy. Here, we report the opinion of the scientific community proposing to replace the "one size fits all" approach with tailor-made nutrition programs, designed by integrating nutrigenomic data together with clinical parameters and microbiota profiles, taking into account the individual lactose tolerance threshold and needs in terms of specific nutrients intake. This customized approach could help LI patients to improve their quality of life, overcoming depression or anxiety often resulting from the individual perception of this condition as different from a normal state.

Technological and health properties and main challenges in the production of vegetable beverages and dairy analogs.

Lactose intolerance affects about 68-70% of the world population and bovine whey protein is associated with allergic reactions, especially in children. Furthermore, many people do not consume dairy-based foods due to the presence of cholesterol and ethical, philosophical and environmental factors, lifestyle choices, and social and religious beliefs. In this context, the market for beverages based on pulses, oilseeds, cereals, pseudocereals and seeds and products that mimic dairy foods showed a significant increase over the years. However, there are still many sensory, nutritional, and technological limitations regarding producing and consuming these products. Thus, to overcome these negative aspects, relatively simple technologies such as germination and fermentation, the addition of ingredients/nutrients and emerging technologies such as ultra-high pressure, pulsed electric field, microwave and ultrasound can be used to improve the product quality. Moreover, consuming plant-based beverages is linked to health benefits, including antioxidant properties and support in the prevention and treatment of disorders and common diseases like hypertension, diabetes, anxiety, and depression. Thus, vegetable-based beverages and their derivatives are viable alternatives and low-cost for replacing dairy foods in most cases.

Lactose Intolerance - Single Nucleotide Polymorphisms and Treatment.

The majority (about 70%) of the world's population suffers from lactose intolerance. Lactose intolerance leads to long-term discomfort when consuming milk and dairy products, and hence, to their avoidance. Consequently, the intake of important nutrients is reduced, which potentially has a negative impact on the overall health. Knowing the condition - lactose intolerance - will prevent people from unnecessarily restricting dairy products in their diets. In this study, lactose synthesis and catabolism in the human body are presented, also the types of lactose intolerance, as well as the methods of diagnosing this condition, are discussed. Special attention is paid to the genetic causes of this discomfort and to the tests that can be performed. Solutions for the treatment of lactose intolerance have also been proposed, both up-to-date and easily applicable, as well as future developments.

This review highlights the lactose pathway ­ from the mammary gland production to recipient gut hydrolysis.Lactose intolerance associated SNPs known so far are presented and discussed.Advice for people with lactose intolerance is presented in the form of possible treatments and healthy feeding behaviors.

A Genetic Lab-on-Phone Test for Point-of-Care Diagnostic of Lactose Intolerance near Patient and in less than 90 Minutes.

BACKGROUND: The -13910 C/T single nucleotide polymorphism located within the MCM6 gene, an enhancer region located upstream of the lactase-phlorizin hydrolase gene, is associated with lactase persistence/non-persistence traits among the Caucasian population. The performance of a new point-of-care CE-IVD (In Vitro Diagnostic) marked isothermal lab-on-phone lactose intolerance assay, using crude samples, was assessed in comparison with Sanger sequencing using purified DNA, as reference method. METHODS: The study was conducted following a non-probability sampling using direct buccal swab (n = 63) and capillary blood (n = 43) clinical samples from a total of 63 volunteers. A 3 × 3 confusion matrix/contingency table was used to evaluate the performance of the isothermal lab-on-phone lactose intolerance assay. RESULTS: The isothermal lab-on-phone lactose intolerance assay successfully detected the -13910 C/T variant with a limit of detection of 5 cells/assay and demonstrated an overall accuracy of 98.41% (95% CI, 91.47%-99.96%) for buccal swab samples and 100% (95% CI, 91.19%-100%) for capillary blood, taking just 90 min from sample to result, with only 2 min hands-on. CONCLUSIONS: The lab-on-phone pocket-sized assay displayed good performance when using direct buccal swab and capillary blood samples, enabling a low-cost, real-time, and accurate genotyping of the -13910 C/T region for the rapid diagnosis of primary lactose intolerance at point-of-care, which enables a prompt implementation of appropriate diet habits and/or intolerance therapies. To our knowledge, this is the first point-of-care genetic test for lactose intolerance to be made available on the market.

Chitosan-based oral hydrogel formulations of ß-galactosidase to improve enzyme supplementation therapy for lactose intolerance.

ß-Galactosidase supplementation plays an important role in the life of people with lactose intolerance. However, these formulations are rendered ineffective by the low pH and pepsin in the stomach and pancreatic proteases in the intestine. Therefore, it is necessary to develop oral transport systems for carrying this enzyme in the active form up to the intestine, where the lactose digestion occurs. In this research, a new hydrogel was developed that could potentially be used for enzyme supplement therapy. In this regard, the chitosan-based ß-Gal formulations described in the manuscript are an alternative long-acting preparation to the so far available preparations that allow for enzyme protection and mucosal targeting. These hydrogels were prepared from chitosan and polyethylene glycol and contained a covalently immobilized ß-galactosidase from Aspergillus oryzae. The ß-galactosidase in the hydrogel was protected from degradation in a gastric medium at a pH of 2.5 and retained 75 % of its original activity under subsequent intestinal conditions. In the case of a simulated gastric fluid with a pH of 1.5, a copolymer containing methacrylic acid functional groups was sufficient to protect the hybrid hydrogel from the extremely acidic pH. In addition, the surface of the hydrogel was chemically modified with thiol and amidine groups, which increased the binding to intestinal mucin by 20 % compared with the unmodified hydrogel. These results represent a promising approach for oral transport as a reservoir for ß-galactosidase in the small intestine to reduce the symptoms of hypolactasia.

Changes in gut microbiota and lactose intolerance symptoms before and after daily lactose supplementation in individuals with the lactase nonpersistent genotype.

BACKGROUND: Approximately 70%-100% of the Asian adult population is lactase nonpersistent (LNP). The literature shows that many individuals with the LNP-genotype can consume ≤12 g of lactose without experiencing gastrointestinal discomfort. Repetitive consumption of lactose may reduce intolerance symptoms via adaptation of the gut microbiota. OBJECTIVE: This study aimed to assess the effects of daily consumption of incremental lactose doses on microbiota composition and function, and intolerance symptoms. METHODS: Twenty-five healthy adults of Asian origin, carrying the LNP-genotype were included in this 12-wk before and after intervention trial. Participants consumed gradually increasing lactose doses from 3 to 6 g to 12 g twice daily, each daily dose of 6 g, 12 g, or 24 g being provided for 4 consecutive weeks. Participants handed-in repeated stool samples and underwent a 25 g lactose challenge hydrogen breath test (HBT) before and after the 12-wk intervention. Daily gastrointestinal symptoms and total symptom scores (TSSs) during the lactose challenge were recorded. RESULTS: A significant increase from 5.5% ± 7.6% to 10.4% ± 9.6% was observed in Bifidobacterium relative abundance after the intervention (P = 0.009), accompanied by a 2-fold increase (570 ± 269 U/g; P < 0.001) in fecal ß-galactosidase activity compared with baseline (272 ± 158 U/g). A 1.5-fold decrease (incremental area under the curve; P = 0.01) in expired hydrogen was observed during the second HBT (38 ± 35 ppm·min), compared with the baseline HBT (57 ± 38 ppm·min). There was a nonsignificant decrease in TSS (10.6 ± 8.3 before compared with 8.1 ± 7.2 after intervention; P = 0.09). Daily consumption of lactose was well tolerated, with mild to no gastrointestinal complaints reported during the intervention. CONCLUSIONS: Increased levels of Bifidobacterium indicate an adaptation of the gut microbiota upon repetitive consumption of incremental doses of lactose, which was well tolerated as demonstrated by reduced expired hydrogen concentrations during the second 25-g lactose HBT. Bifidobacteria metabolize lactose without gas production thereby potentially reducing intestinal gas formation in the gut of individuals with the LNP-genotype. This increased lactose tolerance possibly lifts the necessity to remove nutrient-rich dairy foods completely from the diet. The trial is registered at the International Clinical Trials Registry Platform: NL9516. The effect of dietary lactose in lactase nonpersistent individuals on gut microbiota.

Photoacoustic Spectroscopy-Based Breath Analysis for SIBO.

Breath hydrogen (H2) and methane (CH4) monitoring play an important role in the diagnosis of gastrointestinal disorders, such as lactose intolerance and small intestinal bacterial overgrowth (SIBO). In this paper, the photoacoustic spectroscopy method is used for H2 gas and CH4 gas detection. We present a novel approach for H2 gas concentration measurement, which is the linear relationship between the resonant frequency of breath carbon dioxide (CO2) and the H2 concentration in a resonant photoacoustic cell. Experimental results show that the minimum detectable limits of H2, CH4, and CO2 are calculated to be 8.86, 0.56, and 145.14 ppm, respectively, which can meet the requirements of breath diagnosis.

Myths and Facts about Food Intolerance: A Narrative Review.

Most adverse reactions to food are patient self-reported and not based on validated tests but nevertheless lead to dietary restrictions, with patients believing that these restrictions will improve their symptoms and quality of life. We aimed to clarify the myths and reality of common food intolerances, giving clinicians a guide on diagnosing and treating these cases. We performed a narrative review of the latest evidence on the widespread food intolerances reported by our patients, giving indications on the clinical presentations, possible tests, and dietary suggestions, and underlining the myths and reality. While lactose intolerance and hereditary fructose intolerance are based on well-defined mechanisms and have validated diagnostic tests, non-coeliac gluten sensitivity and fermentable oligosaccharide, disaccharide, monosaccharide, and polyol (FODMAP) intolerance are mainly based on patients' reports. Others, like non-hereditary fructose, sorbitol, and histamine intolerance, still need more evidence and often cause unnecessary dietary restrictions. Finally, the main outcome of the present review is that the medical community should work to reduce the spread of unvalidated tests, the leading cause of the problematic management of our patients.

Lactose malabsorption and intolerance: What is the correct management in older adults?

Lactose malabsorption is a very common condition due to intestinal lactase deficiency. Post weaning, a genetically programmed and irreversible reduction of lactase activity occurs in the majority of the world's population. Lactose malabsorption does not necessarily result in gastrointestinal symptoms, i.e. lactose intolerance, which occurs in approximately one third of those with lactase deficiency. In the absence of well-established guidelines, the common therapeutic approach tends to exclude milk and dairy products from the diet. However, this strategy may have serious nutritional disadvantages. Mainly in particular categories, such as the older adults, the approach to lactose malabsorption may deserve careful considerations. Milk and dairy products are an important supply of a wide range of nutrients that contribute to meet the nutritional needs in different life stages. Dietary composition can significantly impact the mechanisms leading to age-related loss of bone mineral density, skeletal muscle mass or function and overall risk of sarcopenia. Moreover, in the latest years, different lines of evidence have highlighted an association between dairy intake and prevention of chronic diseases as well as all-cause mortality. The aim of this opinion paper is to provide an overview of lactose malabsorption and intolerance in the older adults and their implications in clinical practice.