Fruit intake reduces the onset of respiratory allergic symptoms in schoolchildren

Associations of the planetary health diet index (PHDI) with asthma: the mediating role of body mass index

BACKGROUND

Given the global shifts in environmental conditions and dietary habits, understanding the potential impact of dietary factors and body mass index (BMI) on respiratory diseases, including asthma, is paramount. Investigating these relationships can contribute to the formulation of more effective prevention strategies. The Planetary Health Diet Index (PHDI), a dietary scoring system that balances human health with environmental sustainability, underscores the importance of increasing the consumption of plant-based foods while reducing the intake of red meat, sugar, and highly processed foods. The objective of this study was to assess the association between PHDI and the prevalence of asthma and the mediation effect of BMI in a US general population.

METHODS

This study utilized data from 32,388 participants in the National Health and Nutrition Examination Survey (NHANES) spanning from 2005 to 2018. Multivariate logistic regression and weighted quantile sum (WQS) regressions were employed to investigate the association between PHDI, individual nutrients, and asthma. Restricted cubic spline (RCS) analysis explored the linear or non-linear relationship between PHDI and asthma. Interaction analyses were conducted on subgroups to validate the findings. Mediation analysis was performed to examine the effect of BMI on the relationship between PHDI and asthma.

RESULTS

There was a significant negative association between PHDI and asthma. After adjusting for covariates, for every 10-point increase in PHDI, there was a 4% decrease in the prevalence of asthma (P = 0.025). Moreover, as PHDI increased, there was a trend towards lower asthma prevalence (P for trend < 0.05). WQS analyses showed consistent associations (OR = 0.93, 95%CI: 0.88, 0.98), with Fiber, Vitamin C, and Protein significant factors. The dose-response curve indicated a linear association between PHDI and asthma, with higher PHDI associated with lower asthma prevalence. Additionally, BMI is significantly positively associated with asthma (P < 0.001), and BMI decreases as the PHDI increases (β = -0.64, P < 0.001). Mediation analysis indicates that BMI significantly mediates the relationship between PHDI and asthma, with a mediation proportion of 33.85% (P < 0.001).

CONCLUSION

The results of this study show a strong negative correlation between PHDI and the prevalence of asthma. In addition, BMI mediated this negative relationship.

Dietary Polyphenols, Plant Metabolites, and Allergic Disorders: A Comprehensive Review

Given the ongoing rise in the occurrence of allergic disorders, alterations in dietary patterns have been proposed as a possible factor contributing to the emergence and progression of these conditions. Currently, there is a significant focus on the development of dietary therapies that utilize natural compounds possessing anti-allergy properties. Dietary polyphenols and plant metabolites have been intensively researched due to their well-documented anti-inflammatory, antioxidant, and immunomodulatory characteristics, making them one of the most prominent natural bioactive chemicals. This study seeks to discuss the in-depth mechanisms by which these molecules may exert anti-allergic effects, namely through their capacity to diminish the allergenicity of proteins, modulate immune responses, and modify the composition of the gut microbiota. However, further investigation is required to fully understand these effects. This paper examines the existing evidence from experimental and clinical studies that supports the idea that different polyphenols, such as catechins, resveratrol, curcumin, quercetin, and others, can reduce allergic inflammation, relieve symptoms of food allergy, asthma, atopic dermatitis, and allergic rhinitis, and prevent the progression of the allergic immune response. In summary, dietary polyphenols and plant metabolites possess significant anti-allergic properties and can be utilized for developing both preventative and therapeutic strategies for targeting allergic conditions. The paper also discusses the constraints in investigating and broad usage of polyphenols, as well as potential avenues for future research.

Addressing global health disparities in the management of RSV infection in infants and children: Strategies for preventing bronchiolitis and post-bronchiolitis recurrent wheezing

Background: The topic of equitable access to health care and its impact on exacerbating worldwide inequities in child health not only strikes at the heart of our health-care delivery systems but also deeply resonates with our collective social consciences. Nowhere is this better seen on a global scale than in the burden of illness caused by respiratory syncytial virus (RSV) infection, which extracts the most severe morbidity and mortality in infants and children in low- and middle-income countries (LMIC). This report addresses global health disparities that exist in the management of RSV infection in infants and children, and offers strategies for preventing bronchiolitis and postbronchiolitis recurrent wheezing in LMICs. Methods: A systematic literature review was conducted across the PubMed data bases of RSV infection and the socioeconomic impact of bronchiolitis and postbronchiolitis recurrent wheezing in LMICs. Results: The results of the present study address the many issues that deal with the question if prevention of RSV bronchiolitis can mitigate recurrent wheezing episodes and links RSV risks, downstream effects, prevention, malnutrition, and socioeconomic restraints of developing countries with a call for possible global action. Conclusion: The present study stresses the importance of considering the linkage between malnutrition and disease susceptibility because of the known relationships between undernutrition and greater vulnerability to infectious diseases, including RSV infection. These complex interactions between infectious disease and undernutrition also raise issues on the longer-term sequelae of postbronchiolitis recurrent wheezing. This prompts a discussion on whether industrialized countries should prioritize the provision of newly developed monoclonal antibodies and RSV vaccines to LMICs or whether vital nutritional needs should be a first focus. The resolution of these issues will require research and greater international discourse.

Greater fruit and vegetables consumption, and adherence to a Mediterranean type of diet reduces the risk for asthma in children; a systematic review and meta-analysis

The objective of this study was to explore the relationship between the consumption of fruits, vegetables and adherence to the Mediterranean diet with childhood asthma development and severity. A systematic literature search and synthesis of the results was performed throughout the last two decades. A total of 45 studies were analysed and 392,797 children were included. Greater adherence to a Mediterranean type of diet was inversely associated with asthmatic outcomes (OR:0.71,95% CI:0.54,0.88). Regarding fruits, vegetables consumption, a significant inverse association between increased fruits or vegetable intake and asthma was found (OR:0.82,95% CI:0.77,0.86; 0.84,95% CI:0.77,0.91, respectively). Fruits and vegetables consumption combined was also inversely related to all asthmatic outcomes (OR:0.65,95% CI:0.49,0.78). The level of heterogeneity was moderate-to-high (30%-97%). The present review and meta-analysis show a trend to an inverse association between adherence to the Mediterranean diet or a healthy diet rich in fruits and vegetables and the occurrence of childhood asthma but with a low level of certainty.

Dietary Polyphenols-Natural Bioactive Compounds with Potential for Preventing and Treating Some Allergic Conditions

In light of the constantly increasing prevalence of allergic diseases, changes in dietary patterns have been suggested as a plausible environmental explanation for the development and progression of these diseases. Nowadays, much attention has been paid to the development of dietary interventions using natural substances with anti-allergy activities. In this respect, dietary polyphenols have been studied extensively as one of the most prominent natural bioactive compounds with well-documented anti-inflammatory, antioxidant, and immunomodulatory properties. This review aims to discuss the mechanisms underlying the potential anti-allergic actions of polyphenols related to their ability to reduce protein allergenicity, regulate immune response, and gut microbiome modification; however, these issues need to be elucidated in detail. This paper reviews the current evidence from experimental and clinical studies confirming that various polyphenols such as quercetin, curcumin, resveratrol, catechins, and many others could attenuate allergic inflammation, alleviate the symptoms of food allergy, asthma, and allergic rhinitis, and prevent the development of allergic immune response. Conclusively, dietary polyphenols are endowed with great anti-allergic potential and therefore could be used either for preventive approaches or therapeutic interventions in relation to allergic diseases. Limitations in studying and widespread use of polyphenols as well as future research directions are also discussed.

Longitudinal consumption of fruits and vegetables and risk of asthma by 5 years of age

BACKGROUND

Fruit and vegetable consumption has been linked to a decreased risk of asthma, but prospective evidence on longitudinal consumption in childhood is scarce. We aimed to investigate the association between fruit and vegetable consumption in childhood and the risk of asthma by the age of 5 years, and to explore the role of processing of fruits and vegetables in the Finnish Type 1 Diabetes Prediction and Prevention Allergy Study.

METHODS

Child's food consumption was assessed by 3-day food records completed at the age of 3 and 6 months, and 1, 2, 3, 4, and 5 years, and asthma and allergies by a validated modified version of the ISAAC questionnaire at the age of 5 years. Consumption of processed and unprocessed fruits and vegetables was calculated. Joint models with a current value association structure for longitudinal and time-to-event data were used for statistical analyses.

RESULTS

Of the 3053 children, 184 (6%) developed asthma by the age of 5 years. The risk of asthma was not associated with the consumption of all fruits and vegetables together (HR 1.00, 95%CI 0.99-1.01 per consumption of 1 g/MJ, adjusted for energy and other covariates), or with most subgroups. Weak inverse associations were seen between all leafy vegetables and asthma (HR = 0.87, 0.77-0.99), and unprocessed vegetables and nonatopic asthma (HR = 0.90, 95% CI 0.81-0.98).

CONCLUSION

Total consumption of fruits and vegetables in childhood was not associated with the development of asthma by the age of 5 years. Weak inverse associations found for vegetables need to be confirmed or rejected in future studies.

Fruit, vegetable and dietary antioxidant intake in school age, respiratory health up to young adulthood

BACKGROUND

Dietary antioxidants may protect the lung against oxidative damage and prevent chronic respiratory disease. We aimed to investigate fruit, vegetable and antioxidant intake (measured as total antioxidant capacity, TAC) at age 8 years in relation to asthma and lung function up to 24 years.

METHODS

In this study of 2506 participants from a Swedish birth cohort, diet was assessed using food frequency questionnaires. Information on asthma was collected by questionnaires, and lung function was measured by spirometry at ages 8, 16 and 24 years. Generalized estimating equations and mixed effect models were used to assess overall, age- and sex-specific associations.

RESULTS

After adjustment for confounders, a higher fruit intake at age 8 years was associated with a tendency to reduced odds of prevalent asthma (T3 vs. T1, OR 0.78; 95% CI 0.60-1.01, p-trend .083), with reduced odds of incident asthma and increased odds of remittent asthma (≥median, OR 0.76; 95% CI 0.58-0.99 and OR 1.60; 95% CI 1.05-2.42, respectively) up to 24 years. Comparable, but non-significant, odds ratios were observed in analyses of long-term fruit intake (mean intake at ages 8 and 16 years). In contrast, no association was observed with vegetable intake. A higher dietary TAC (T3 vs. T1) at 8 years was associated with reduced odds of prevalent asthma (OR 0.73; 95% CI 0.58-0.93, p-trend .010) and improved lung function development (FEV₁ -z +0.11; 95% CI 0.01-0.21, p-trend .036 and FVC-z +0.09; 95% CI -0.01-0.20, p-trend .072) up to 24 years. Associations were more pronounced among males, and regarding asthma, participants sensitized to aeroallergens.

CONCLUSIONS

Antioxidant intake in school age may improve asthma and lung function up to young adulthood. Although our results should be interpreted with caution, they emphasize the importance of following current dietary guidelines regarding consumption of antioxidant-rich foods as part of a balanced diet.

Higher diversity of vegetable consumption is associated with less airway inflammation and prevalence of asthma in school-aged children

BACKGROUND

A diet rich in fruits and vegetables has been suggested to counteract the oxidative stress and inflammation that characterize asthma. We aimed to assess the association between vegetable and fruit diversity consumption and asthma and its related outcomes in school-aged children.

METHODS

Participants included 647 children (49% females, aged 7-12 years) recruited from 20 public schools across the city of Porto, in Portugal. Vegetable intake and fruit intake were ascertained using a single self-reported 24-hour recall questionnaire. A diversity score was built taking into account the different number of individual vegetables and fruits consumed and categorized into two groups based on the total reported median consumption, which was rounded to the nearest whole number (≤3 and >3, for vegetables; and ≤1 and >1, for fruits). A questionnaire was used to enquire about self-reported medical diagnosis of asthma and respiratory symptoms. Airway inflammation was assessed measuring exhaled fractional nitric oxide concentration (eNO) and was categorized into two groups (<35 and ≥35 ppb). The association between fruit and vegetable diversity and respiratory outcomes was examined using logistic regression models, adjusting for confounders.

RESULTS

A higher vegetable diversity consumption per day was negatively associated with having self-reported asthma (OR = 0.67; 95% CI 0.47, 0.95), while having a vegetable diversity consumption superior to 3 items per day was negatively associated with levels of eNO ≥ 35 ppb (OR = 0.38; 95% CI 0.16, 0.88) and breathing difficulties (OR = 0.39; 95% CI 0.16, 0.97).

CONCLUSION

Eating a greater variety of vegetables was associated with a lower chance of airway inflammation and prevalence of self-reported asthma in school children.

Parental Education and the Association between Fruit and Vegetable Consumption and Asthma in Adolescents: The Greek Global Asthma Network (GAN) Study

BACKGROUND

Evidence suggests that nutritional factors, such as consumption of fruits and vegetables, along with socioeconomic factors such as parental education level, are associated with asthma prevalence. Our study examined the role of parental education in the association between fruit and vegetable consumption and adolescent asthma.

METHODS

1934 adolescents (mean age: 12.7 years, standard deviation: 0.6 years, boys: 47.5%) and their parents were voluntarily enrolled and completed a validated questionnaire assessing current asthma status, fruit and vegetable consumption and parental educational level. Participants were categorized as high or low intake for five food groups: fruits, cooked vegetables, raw vegetables, all vegetables (cooked and raw), and all three food groups together (fruits and all vegetables).

RESULTS

Adolescents who were high consumers of all three food groups (fruits, cooked and raw vegetables) were less likely to have asthma, adjusted for several confounders (adjusted odds ratio (aOR): 0.53, 95% confidence interval (CI): 0.25-0.97). Moreover, in adolescents who had parents with tertiary education and were in the high consumption of all three food groups, the inverse association was almost twofold higher than the one for adolescents with parents of primary/secondary education (aOR: 0.35, 95% CI: (0.21-0.89) and aOR: 0.61, 95% CI: (0.47-0.93) respectively).

CONCLUSIONS

Our findings highlight the importance of the adoption of a diet rich in fruits and vegetables for all asthmatic adolescents and emphasize the important role of parental influences in this association.

Negative Association in Reported Dietary Energy Intake and Physique in Japanese Schoolchildren

Appropriate dietary assessment and health education are necessary for children to achieve a healthy physique. To explore the relationship between habitual reported dietary energy intake (EI) and physique in elementary schoolchildren by sex and age, we conducted a longitudinal study, in the fiscal year 2011, that included all elementary schools in Omihachiman City, Shiga Prefecture, Japan. The study lasted for four consecutive years, ending in fiscal year 2014, and included 545 7-y-old schoolchildren in the target city. The subjects completed a brief self-administered diet history questionnaire with their guardians. The results of the study demonstrated a negative relationship between energy intake and the estimated energy requirement ratio and body mass index percentile values for both 7-, 9-, and 10-y-old boys and 7- to 10-y-old girls. These results suggest that there is a need to keep in consideration the under-reporting of obese children and over-reporting of lean children for dietary energy evaluation.

Vegetable dietary pattern may protect mild and persistent allergic rhinitis phenotype depending on genetic risk in school children

BACKGROUND

The effect of diet on allergic rhinitis (AR), its severity in children, and whether it modifies AR depending on genetic susceptibility are unknown. We investigated the association between dietary patterns and AR in school children and the influence of diet on AR according to a genetic risk score (GRS).

METHODS

Totally, 435 7-year-old school children were recruited from the Panel Study on Korean Children. We used dietary patterns (vegetable, sugar, and meat) and dietary inflammatory index (DII) as dietary parameters. AR and its severity were defined by questionnaires about treatment in the previous 12 months and the Allergic Rhinitis and its Impact on Asthma (ARIA) guideline, respectively. A GRS was calculated using 6 single nucleotide polymorphisms for allergic diseases.

RESULTS

A vegetable diet containing a lot of anti-inflammatory nutrients and higher vitamin D level in blood were negatively correlated, while DII was positively correlated with triglyceride level and triglyceride/HDL cholesterol. Vegetable diet (aOR, 95% CI = 0.73, 0.58-0.94) and DII (1.13, 1.01-1.28) were associated with AR risk. In particular, a high-vegetable diet resulted in a lower risk of mild and persistent AR (aOR, 95% CI = 0.24, 0.10-0.56) while a high DII represented a higher risk (2.33, 1.06-5.10). The protective effect of vegetable diet on AR appeared only among children with a lower GRS (adjusted P = .018).

CONCLUSIONS

A vegetable dietary pattern characterized by high intake of anti-inflammatory nutrients and higher vitamin D level in blood might be associated with a lower risk of mild and persistent AR. This beneficial effect is modified by a genetic factor.

Nutritional Issues in Food Allergy

Diet and nutrition play an important role in the development and management of food allergy. The diet of expectant mothers can have an effect on their offspring in terms of allergic outcomes. A host of confounding factors may influence this, with a maternal diet rich in fruits and vegetables, fish, vitamin D-rich foods associated with a lower risk of allergic disease in their children. More surprisingly, the consumption of milk and butter has also been shown to have a protective effect, especially in a farm environment. Similarly, the diet of the infant can also be important, not only in terms of breast feeding, but also the timing of the introduction of complementary foods, the diversity of the diet and the effect of individual foods on the development of allergy. One factor which has clearly been shown not to influence the development of food allergy is allergen avoidance by expectant mothers. In the infant diet, the manipulation of the gut microbiome to prevent the development of atopic disease is clearly an area which promises much, although studies have yet to provide a breakthrough in the prevention of atopic dermatitis. More concrete evidence of the value of diet in prevention has come from studies evaluating infant eating patterns which may protect gut health, through the consumption of large amounts of home-processed fruits and vegetables. The consumption of fish during the first year of life has also been shown to be protective. The importance of nutritional issues in children and adults who have a food allergy has become much more accepted in recent years. The primary allergenic foods in infancy and childhood, milk, egg, wheat and soy are also ones which are present in many foods and thus their avoidance can be problematic from a nutritional perspective. Thus, children with a food allergy can have their growth compromised through avoidance, especially pre-diagnosis, when foods may be excluded without any expert nutritional input. The management of a food allergy largely remains the exclusion of the offending food(s), but it is now clear that in doing so, children in particular can be at nutritional risk if insufficient attention is paid to the rest of the diet. Adults with food allergy are often thought not to need nutritional counselling; however, many will exclude a wide range of foods due to anxiety about trace exposure, or similar foods causing reactions. The avoidance of staple foods such as milk and wheat are common, but substitute foods very often do not have comparable nutritional profiles. Adults may also be more susceptible to on-line promotion of extreme nutritional regimes which can be extremely harmful. All food allergic individuals, whatever their age, should have a nutrition review to ensure they are consuming a healthy, balanced diet, and are not avoiding food groups unnecessarily.

Dietary antioxidant intake in school age and lung function development up to adolescence

Dietary antioxidant intake has been hypothesised to influence lung function. The association between total antioxidant capacity (TAC) of the diet at age 8 years and lung function development up to 16 years in 2307 participants from the Swedish population-based birth cohort BAMSE (Children, Allergy, Milieu, Stockholm, Epidemiology) was investigated.

Information on TAC was obtained from a food frequency questionnaire at 8 years. Lung function was measured by spirometry at 8 and 16 years, impulse oscillometry (IOS) and exhaled nitric oxide fraction (F_eNO) at 16 years. Low lung function was defined as forced expiratory volume in 1 s (FEV₁) z-score below the 25th percentile. Longitudinal associations between TAC and lung function were analysed by mixed effect models adjusted for potential confounders. Stratification by asthma at 8 years was performed to examine effect modification.

The median TAC intake was 10 067 μmol Trolox equivalents (TE)·g⁻¹, with males having a lower mean compared to females (9963 versus 10 819 μmol TE·g⁻¹). In analyses of lung function change between 8 and 16 years, there were no statistically significant associations between TAC in tertiles and spirometry results for the total study population. Among children with asthma at 8 years (prevalence 7%), higher TAC was associated with higher mean FEV₁ (0.46 sd, 95% CI 0.11–0.80) and decreased odds of low lung function at 16 years (OR 0.28, 95% CI 0.12–0.65). There were no associations between TAC and forced vital capacity or IOS/F_eNO results.

High dietary antioxidant intake in school age may be associated with improved lung function development from school age to adolescence among children with asthma.

Dietary antioxidant intake at school age may influence lung function development as measured by FEV₁ up to adolescence among children with asthma. In contrast, no association was observed among children without asthma.http://bit.ly/2CzEZ8W

Effect of Dietary Fiber and Metabolites on Mast Cell Activation and Mast Cell-Associated Diseases

Many mast cell-associated diseases, including allergies and asthma, have seen a strong increase in prevalence during the past decades, especially in Western(ized) countries. It has been suggested that a Western diet may contribute to the prevalence and manifestation of allergies and asthma through reduced intake of dietary fiber and the subsequent production of their metabolites. Indeed, dietary fiber and its metabolites have been shown to positively influence the development of immune disorders via changes in microbiota composition and the regulation of B- and T-cell activation. However, the effects of these dietary components on the activation of mast cells, key effector cells of the inflammatory response in allergies and asthma, remain poorly characterized. Due to their location in the gut and vascularized tissues, mast cells are exposed to high concentrations of dietary fiber and/or its metabolites. Here, we provide a focused overview of current findings regarding the direct effects of dietary fiber and its various metabolites on the regulation of mast cell activity and the pathophysiology of mast cell-associated diseases.