Dietary sodium intake and asthma: an epidemiological and clinical review

Abstract

The changes in diet associated with the development of a more affluent lifestyle have been considered one of the environmental factors that may have contributed to the rise in the prevalence of asthma over the past few decades, and dietary sodium has been considered to be a dietary constituent which may be implicated in this phenomenon. The data presented in this review demonstrate that adoption of a low sodium diet for a period of 2-5 weeks may improve lung function and decrease bronchial reactivity in adults with asthma, while sodium loading appears to have a detrimental effect. Similarly, a low sodium diet maintained for 1-2 weeks decreases bronchoconstriction in response to exercise in individuals with asthma. There is no data as to the longer-term effect of a low sodium diet on either the prevalence or severity of asthma or on exercise-induced bronchoconstriction. As a low sodium diet has other beneficial health effects, it can be considered as a therapeutic option for adults with asthma, although it should be considered as an adjunctive intervention to supplement optimal pharmacological management of asthma and not as an alternative. If the relationship between higher sodium intake and increased prevalence and severity of asthma is causal, then there are potential population benefits for asthma as well as cardiovascular disease to be derived from public health measures to reduce sodium consumption.

Dietary factors associated with lifetime asthma or hayfever diagnosis in Australian middle-aged and older adults: a cross-sectional study

“…High-meat diets may be linked with fast food or takeaway consumption, typically high in sodium and saturated fat, and implicated in asthma [53,62,63]. The issue of risk from saturated fat poses an explanatory problem with regard to cheese, however, as cheese loaded on a protective factor with brown and whole-meal bread for females, but on a risk factor with red and processed meats for males.…”

Cross-modal interactions between taste and smell: Odour-induced saltiness enhancement depends on salt level

“…Salt overconsumption has been linked to the development of hypertension, cardiovascular disease and other health problems (Mickleborough & Fogarty, 2006). Indeed, excessive sodium intake leads to water retention and to an increase in blood volume that might trigger an elevation in blood pressure (Strazzullo, D'Elia, Kandala, & Cappuccio, 2009).…”

Exercise-Induced Asthma

“…A number of epidemiological and cross-sectional studies have demonstrated a strong association between salt intake and asthma, i.e., that a higher salt intake may potentiate asthma severity (19). These earlier epidemiological and cross-sectional studies led to several subsequent small interventional studies that have shown that a salt-restricted diet can improve pulmonary function, reduce symptoms and medication use, and reduce airway hyperresponsiveness, compared with a high-salt diet (HSD), in individuals with asthma (19).…”

“…These earlier epidemiological and cross-sectional studies led to several subsequent small interventional studies that have shown that a salt-restricted diet can improve pulmonary function, reduce symptoms and medication use, and reduce airway hyperresponsiveness, compared with a high-salt diet (HSD), in individuals with asthma (19). Although these studies do support the concept of a relationship between sodium intake and asthma severity, a large, randomized, controlled clinical trial recently reported on a double-blind, placebo-controlled, randomized parallel-group (low-salt diet [LSD] and normal-salt diet [NSD]) study that found that a 6-wk LSD did not improve asthma control and bronchial reactivity in 199 adults with mild-to-moderate asthma (34).…”