Salt intake and prevalence of overweight/obesity in Japan, China, the United Kingdom, and the United States: the INTERMAP Study

Abstract

Background Several studies have reported that dietary salt intake may be an independent risk factor for overweight/obesity, but results from previous studies are controversial, reflecting study limitations such as use of a single spot urine or dietary recall to estimate daily salt intake rather than 24-h urine collections, and population samples from only a single country or center. Objective The aim of this study was to use data from the International Study of Macro-/Micro-nutrients and Blood Pressure (INTERMAP Study) to explore the relation between dietary salt intake estimated from 2 timed 24-h urine collections and body mass index (BMI; in kg/m2) as well as prevalence of overweight/obesity in Japan, China, the United Kingdom, and the United States. Methods Data were from a cross-sectional study of 4680 men and women aged 40–59 y in Japan (n = 1145), China (n = 839), the United Kingdom (n = 501), and the United States (n = 2195). General linear models were used to obtain the regression coefficients (β) of salt intake associated with BMI. Multivariable logistic regression models were used to determine the ORs and 95% CIs of overweight/obesity associated with a 1-g/d higher dietary salt intake. Results After adjustment for potential confounding factors including energy intake, salt intake 1 g/d higher was associated with BMI higher by 0.28 in Japan, 0.10 in China, 0.42 in the United Kingdom, and 0.52 in the United States, all P values < 0.001. Salt intake 1 g/d higher was associated with odds of overweight/obesity 21% higher in Japan, 4% higher in China, 29% higher in the United Kingdom, and 24% higher in the United States, all P values < 0.05. Conclusions Salt intake is positively associated with BMI and the prevalence of overweight/obesity in Japan, China, the United Kingdom, and the United States. This association needs to be further confirmed in well-designed prospective studies with repeated dietary and BMI measurements.This trial was registered at clinicaltrials.gov as NCT00005271.

Diet, Lifestyle, Smoking

“…Salt (Table 1) 1.3.1 Effects on CVD Risk Factors Extensive scientific evidence shows that reducing dietary salt (sodium chloride) intake significantly decreases systolic and diastolic blood pressure in adults with or without hypertension (He et al 2013;Stamler et al 2018). Recent data from the international multicentre population INTERMAP study reported a positive association between salt intake and blood pressure values also within the normal range (Zhou et al 2019). In addition to sodium reduction, an increase in potassium intake is beneficial to prevent and control blood pressure in people with hypertension, with no adverse effects on plasma lipid concentrations (Aburto et al 2013a).…”

Salt need needs investigation

“…The determinants of our excessive salt appetite have been scarcely researched and, consequently, are scarcely understood (14)(15)(16)(17)(18) . Research has been primarily into the consequences of salt intake, primarily comprising large-scale studies, which have engendered the consensus that salt is toxic, along with a nuanced contention that it is less so (7,(9)(10)(11)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27) .…”

“…Today, worldwide, salt is consumed daily, repeatedly, totalling an amount that is in excess of that required to preserve life, which many hold to increase society's disease burden, vascular and cancerous, significantly and cause three million deaths annually (7) . Obesity is estimated to cause four million deaths (8) , but a million of those may be due to salt intake (9)(10)(11) , so that while the two may be similarly deadly, the causes of obesity are researched incomparably more (12,13) . The reason for this is not clear, but it may be that obesity is prominently visible, whereas salt is allied to a silent killer, hypertension (13) .…”

Sodium and Potassium Intakes and Cardiovascular Risk Profiles in Childhood Cancer Survivors: The SCCSS-Nutrition Study

“…Diets low in sodium (Na) and high in potassium (K) have been shown to reduce blood pressure and lower the risk of cardiovascular events and mortality in the general adult population [10,[15][16][17]. The World Health Organization (WHO) recommends restricting Na intake (<2 g/day) and increasing K intake (>3.5 g/day) [16,17] but high sodium consumption is still common [15,18], particularly among obese persons [19,20], and may pose particular problems for CCSs, since their background CVD risk is higher. We know surprisingly little about the dietary intake of Na and K among CCSs, so we set out to assess Na and K intakes of CCSs based on FFQs and morning fasting urine spot samples.…”