Study on influence of age, gender and genetic variants on lactose intolerance and its impact on milk intake in adult Asian Indians

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.

Subjective, but not documented, lactose intolerance accompanies irritable bowel syndrome

Introduction

Lactose intolerance, due to lactase deficiency, may overlap with the symptoms of irritable bowel syndrome (IBS) or lead to an incorrect diagnosis of IBS. Identification of lactose intolerance and lactase deficiency enables targeted treatment to be implemented.

The aim of the study was to search for a frequency of a lactose intolerance symptoms in patients with IBS, depending on the results of hydrogen breath test (HBT).

Materials and Methods

The study involved 56 patients with IBS and 23 healthy people. Both, IBS patients and healthy controls, were asked to complete a survey about IBS symptoms and tolerance of lactose-containing products. A HBT was performed on all subjects.

Results

Lactase deficiency was diagnosed in 60.7% of patients with IBS and 43.5% of control group. The differences between the study groups were not statistically significant. No statistically significant differences were observed between the incidence of lactase deficiency depending on the type of IBS.

In the group of patients with IBS and normal HBT results, as well as in patients with IBS and lactase deficiency, there were no statistically significant differences in the frequency of lactose intolerance symptoms. However, among people with normal HBT results, patients with IBS reported symptoms of intolerance after consuming lactose-containing foods significantly more often compared to the control group (p<0.05).

Conclusions

Frequency of lactase deficiency does not differ between IBS patients and healthy individuals. Patients with IBS are more likely to report symptoms of lactose intolerance, regardless of the HBT result, compared to healthy individuals.

Association between milk consumption and lactose malabsorption in Indonesian children

OBJECTIVES

To study the association between milk consumption and lactose malabsorption in Indonesian children aged 3-12 years.

METHODS

This cross sectional study was conducted in randomly selected presumed healthy children with good nutritional status aged 3-12 years in Central Jakarta, Indonesia (n=174), including 72 children aged 3-5 years and 102 children aged 6-12 years.

RESULTS

The prevalence of lactose malabsorption in children aged 3-5 years and children aged 6-12 years was 20.8% (15/72) and 35.3% (36/102), respectively. There was no association between milk or milk product consumption and lactose malabsorption (P>0.05). In the 51 children with lactose malabsorption, the predominant clinical symptoms were diarrhea (62%), abdominal pain (52%), and nausea (5%) during the hydrogen breath test.

CONCLUSIONS

There is no association between milk consumption and lactose malabsorption in Indonesian children aged 3-12 years, suggesting that genetic predisposition may be more important than adaptive mechanisms to lactose consumption.

Gender, Age, Race and Lactose Intolerance: Is There Evidence to Support a Differential Symptom Response? A Scoping Review

Research evaluating the relationship between lactose intolerance (LI) symptoms and age, gender and race is reviewed. An exhaustive search was conducted on the Google Scholar and PubMed databases. The evidence suggests that women, the elderly or specific racial groups are not more susceptible to LI, but rather dose, body size and genetic differences in lactase non-persistence (LNP) are the primary drivers of intolerance symptoms.

In silico assessment data of allergenicity and cross-reactivity of NP24 epitopes from Solanum lycopersicum (Tomato) fruit

This paper describes data on allergies caused by food (vegetable) and their negative impact on the nutritional balance of the human body. Allergic responses to vegetables such as tomatoes, capsicum and spinach are next to fish, eggs and nuts. Epitopes such as NP24 (allergens) are one of the salt-induced allergenic proteins found in the thaumatin-like protein (TLP) family. The mechanism of allergenicity of TLP found in Solanum lycopersicum (Tomato) fruit is poorly studied. Here we demonstrated allergenicity conferred by the NP24 protein found in Tomato. The data on the cross-reactivity of NP24 protein was generated using Allergen Online and Allermatch tools. Tomato allergenic protein epitope shows a significant identity of with allergens reported in Capsicum, Olive, Kiwi, Tobacco and Banana allergens. Hence, the datasets of sequences, comparative analysis and homology epitope mapping over three dimensional (3D) structures revealed that NP24 has higher cross-reactivity to Capsicum and Tobacco proteins. Thus, this data probably act as limelight for planning wet lab experiments.

Lactase Non-persistence and Lactose Intolerance

PURPOSE OF REVIEW

To evaluate the clinical and nutritional significance of genetically determined lactase non-persistence and potential lactose and milk intolerance in 65-70% of the world's adult population.

RECENT FINDINGS

Milk consumption is decreasing in the USA and is the lowest in countries with a high prevalence of lactase non-persistence. The dairy industry and Minnesota investigators have made efforts to minimize the influence of lactose intolerance on milk consumption. Some lactose intolerant individuals, without co-existent irritable bowel syndrome, are able to consume a glass of milk with a meal with no or minor symptoms. The high frequency of lactase persistence in offspring of Northern European countries and in some nomadic African tribes is due to mutations in the promoter of the lactase gene in association with survival advantage of milk drinking. Educational and commercial efforts to improve calcium and Vitamin D intake have focused on urging consumption of tolerable amounts of milk with a meal, use of lowered lactose-content foods including hard cheeses, yogurt, and lactose-hydrolyzed milk products.

Associations of the MCM6-rs3754686 proxy for milk intake in Mediterranean and American populations with cardiovascular biomarkers, disease and mortality: Mendelian randomization

Controversy persists on the association between dairy products, especially milk, and cardiovascular diseases (CVD). Genetic proxies may improve dairy intake estimations, and clarify diet-disease relationships through Mendelian randomization. We meta-analytically (n ≤ 20,089) evaluated associations between a lactase persistence (LP) SNP, the minichromosome maintenance complex component 6 (MCM6)-rs3754686C>T (nonpersistence>persistence), dairy intake, and CVD biomarkers in American (Hispanics, African-American and Whites) and Mediterranean populations. Moreover, we analyzed longitudinal associations with milk, CVD and mortality in PREDIMED), a randomized Mediterranean diet (MedDiet) intervention trial (n = 7185). The MCM6-rs3754686/MCM6-rs309180 (as proxy), LP-allele (T) was strongly associated with higher milk intake, but inconsistently associated with glucose and lipids, and not associated with CVD or total mortality in the whole population. Heterogeneity analyses suggested some sex-specific associations. The T-allele was associated with higher CVD and mortality risk in women but not in men (P-sex interaction:0.005 and 0.032, respectively), mainly in the MedDiet group. However, milk intake was not associated with CVD biomarkers, CVD or mortality either generally or in sub-groups. Although MCM6-rs3754686 is a good milk intake proxy in these populations, attributing its associations with CVD and mortality in Mediterranean women to milk is unwarranted, as other factors limiting the assumption of causality in Mendelian randomization may exist.