Dietary intake, lung function and airway inflammation in Mexico City school children exposed to air pollutants

Abstract

IntroductionAir pollutant exposure has been associated with an increase in inflammatory markers and a decline in lung function in asthmatic children. Several studies suggest that dietary intake of fruits and vegetables might modify the adverse effect of air pollutants.MethodsA total of 158 asthmatic children recruited at the Children's Hospital of Mexico and 50 non-asthmatic children were followed for 22 weeks. Pulmonary function was measured and nasal lavage collected and analyzed every 2 weeks. Dietary intake was evaluated using a 108-item food frequency questionnaire and a fruit and vegetable index (FVI) and a Mediterranean diet index (MDI) were constructed. The impact of these indices on lung function and interleukin-8 (IL-8) and their interaction with air pollutants were determined using mixed regression models with random intercept and random slope.ResultsFVI was inversely related to IL-8 levels in nasal lavage (p < 0.02) with a significant inverse trend (test for trend p < 0.001), MDI was positively related to lung function (p < 0.05), and children in the highest category of MDI had a higher FEV1 (test for trend p < 0.12) and FVC (test for trend p < 0.06) than children in the lowest category. A significant interaction was observed between FVI and ozone for FEV1 and FVC as was with MDI and ozone for FVC. No effect of diet was observed among healthy children.ConclusionOur results suggest that fruit and vegetable intake and close adherence to the Mediterranean diet have a beneficial effect on inflammatory response and lung function in asthmatic children living in Mexico City.

Scottish Primary School Children Who Consume Greater Levels of Fruit and Vegetables Have Improved Health Markers

“…However, increased in WC, WHR and WHtR was observed with increased fruit intake which was not expected. correlated with lung function (FEV1-FVC) among adults in both a cohort study [76] and a cross-sectional study [77] [78], as well as among children in a crosssectional study [40], and a cohort study [42].…”

“…The potential mechanism behind such a relationship is also unclear [37] [38] [39]. In addition, many cross-sectional studies have shown that F & V intake is correlated with improved lung function in children, which may be related to the high content of Vitamin C [40] [41] [42]. F & V are considered to have a rich content of antioxidants, like Vitamin C; and if taken in large amounts can lead to better lung functioning as antioxidants modulate the adverse effect of ozone (O 3 ) on lung function as well as the resulting airway inflammatory response [41].…”

Asthma in Latin America

“…[44][45][46] Other studies have focused on global diet instead of vitamins or nutrients, reporting that fast food 47 or a 'Western' dietary pattern 48 is associated with higher asthma risk in Mexico and Brazil, while higher fruit and vegetable intake or a 'Mediterranean' diet is associated with reduced airway inflammation and higher lung function in Mexican children. 49 In one of few clinical trials of nutrients and asthma in Latin America, docosahexaenoic acid supplementation in the second and third trimesters of pregnancy led to lower risk (aOR=0.76, Figure 1 Prevalence of childhood asthma in Latin America. 5 7-9 Prevalence in the Dominican Republic is based on adult asthma.…”

Influence of poverty and infection on asthma in Latin America

“…A diet rich in fish is associated with elevated levels of selenium and zinc [80] and in many Latin American populations, wherein fish is frequently cooked in palm oil, with high levels of vitamin A. Selenium, zinc and vitamin A have antioxidant effects and have been associated with protection against asthma [75]. In Latin America, data from Mexico showed that children adherent to a 'Mediterranean' diet have less asthma [79,81]. Data from urban Brazil showed a one-third reduction in the prevalence of nonatopic asthma associated with fish consumption (S. D'Innocenzo, M.L.…”