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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. [ABSTRACT FROM AUTHOR]

Background: Available data have indicated independent direct relations of dietary animal protein and meat to the blood pressure (BP) of individuals. Objective: In this study, we aimed to assess whether BP is associated with the intake of dietary amino acids higher relatively in animal than in vegetable protein (alanine, arginine, aspartic acid, glycine, histidine, lysine, methionine, and threonine). Design: The study was a cross-sectional epidemiologic study that involved 4680 persons aged 40-59 y from 17 random population samples in the People's Republic of China, Japan, the United Kingdom, and the United States. BP was measured 8 times at 4 visits; dietary data (83 nutrients and 18 amino acids) were from four 24-h dietary recalls and two 24-h urine collections. Results: Dietary glycine and alanine (the percentage of total protein intake) were considered singly related directly to BP; with these 2 amino acids together in regression models (from model 1, which was controlled for age, sex, and sample, to model 5, which was controlled for 16 possible confounders), glycine, but not alanine, was significantly related to BP. Estimated average BP differences associated with a 2-SD higher glycine intake (0.71 g/24 h) were 2.0-3.0-mm Hg systolic BP (z = 2.974.32) stronger in Western than in East Asian participants. In Westerners, meat was the main dietary source of glycine but not in East Asians (Chinese: grains/ flour and rice/noodles; Japanese: fish/shellfish and rice/noodles). Conclusion: Dietary glycine may have an independent adverse effect on BP, which possibly contributes to direct relations of animal protein and meat to BP. [ABSTRACT FROM AUTHOR]

Background: Epidemiologic evidence suggests that fruit consumption may lower, the risk of cardiovascular diseases through blood pressure (BP)-lowering effects; little is known on the independent effect of raw fruit and fruit juice on BP. Objective: The objective was to quantify associations of raw fruit and fruit juice consumption with BP by using cross-sectional data from the INTERnational study on MAcro/micronutrients and blood Pressure (INTERMAP) of 4680 men and women aged 40-59 y from Japan, China, the United Kingdom, and the United States. Design: During 4 visits, 8 BP, four 24-h dietary recalls, and two 24-h urine samples were collected. Country-specific multivariate-controlled linear regression coefficients, including adjustment for urinary sodium excretion, were estimated and pooled, weighted by inverse of their variance. Results: The average total raw fruit consumption varied from a mean ± SD of 52 ± 65 g/1000 kcal in the United States to 68 ± 70 g/1000 kcal in China. Individual raw fruit intake was not associated with BP in pooled analyses for all countries or in participants from Western countries, although a positive association with diastolic BP was observed in East Asian participants (per 50 g/1000 kcal; 0.37 mm Hg; 95% CI: 0.02, 0.71). Positive relationships with diastolic BP were found for citrus fruit intake in Western consumers (per 25 g/1000 kcal; 0.47 mm Hg; 95% CI: 0.12, 0.81) and for apple intake in East Asian consumers (0.40 mm Hg; 95% CI: 0.03, 0.78). Among East Asian banana consumers, banana intake was inversely associated with diastolic BP (- 1.01 mm Hg; 95% CI: -1.88, -0.02). Fruit juice intake, which was negligible in Asia, was not related to BP in Western countries. Conclusion: Consistent associations were not found between raw fruit and fruit juice consumption of individuals and BP. This observational study was registered at www.clinicaltrials.gov as NCT00005271. [ABSTRACT FROM AUTHOR]

Abstract: Public health campaigns in several countries encourage population-wide reduced sodium (salt) intake, but excessive intake remains a major problem. Excessive sodium intake is independently related to adverse blood pressure and is a key factor in the epidemic of prehypertension/hypertension. Identification of food sources of sodium in modern diets is critical to effective reduction of sodium intake worldwide. We used data from the INTERMAP Study to define major food sources of sodium in diverse East Asian and Western population samples. INTERMAP is an international, cross-sectional, epidemiologic study of 4, 680 individuals ages 40 to 59 years from Japan (four samples), People''s Republic of China (three rural samples), the United Kingdom (two samples), and the United States (eight samples); four in-depth, multipass 24-hour dietary recalls/person were used to identify foods accounting for most dietary sodium intake. In the People''s Republic of China sample, most (76%) dietary sodium was from salt added in home cooking, about 50% less in southern than northern samples. In Japan, most (63%) dietary sodium came from soy sauce (20%), commercially processed fish/seafood (15%), salted soups (15%), and preserved vegetables (13%). Processed foods, including breads/cereals/grains, contributed heavily to sodium intake in the United Kingdom (95%) and the United States (for methodological reasons, underestimated at 71%). To prevent and control prehypertension/hypertension and improve health, efforts to remove excess sodium from diets in rural China should focus on reducing salt in home cooking. To avoid excess sodium intake in Japan, the United Kingdom, and the United States, salt must be reduced in commercially processed foods. [Copyright &y& Elsevier]

Objective: The present study aims to compare 24-h dietary recalls with 24-h urine collections for the estimation of sodium intake at both population and individual levels in China, Japan, the United Kingdom (UK), and the United States of America (USA), using data from the International Study of Macro- and Micro-nutrients and Blood Pressure (INTERMAP)., Methods: Mean differences between 24-h dietary recalls and 24-h urine collections were calculated for their agreement in estimating sodium intake at the population level; relative and absolute differences as well as misclassification of salt intake groups (salt intake <6, 6-8.9, 9-11.9, 12-14.9, and ≥15 g/day) were used to determine the agreement at the individual level., Results: The mean differences (95% CI) between dietary recalls and urine collections for China, Japan, UK, and USA were -54.0 (-59.8, -48.3), 3.9 (0.6, 7.2), 2.9 (-1.8, 7.6), and -3.5 (-5.8, -1.1) mmol/day, respectively. The proportions of individual relative differences beyond ±40% were 34.3% for China, 16.9% for Japan, 24.2% for UK, and 21.3% for USA; the proportions of individual absolute differences greater than 51.3 mmol/day (3 g salt) were 58.6% for China, 32.8% for Japan, 25.4% for UK, and 31.9% for USA. The rate for misclassification of salt intake groups at individual level for China, Japan, UK, and USA were 71.4, 60.9, 58.7, and 60.0%, respectively., Conclusion: The 24-h dietary recalls demonstrate greater agreement with the 24-h urine collections in estimating population sodium intake for Japan, UK, and USA, compared with China. The 24-h dietary recall has poor performance in assessing individual sodium intake in these four countries.

Objective: Habitual high-salt intake raises blood pressure and risk of cardiovascular diseases. To prevent/control these risks, reduced salt diet (RSD) is recommended in many countries and some people report practicing it; however, little is known about actual achievement. This population-based study assessed level of 24-h dietary sodium intake of participants reporting RSD and others., Method: Participants were 4680 men and women ages 40-59 years randomly selected from 17 populations in People's Republic of China (PRC), Japan, UK and USA, for an observational study on diet and blood pressure (INTERMAP). Daily sodium intake was determined by two timed 24-h urine collections. Antihypertensive treatment status and RSD were ascertained by questionnaire., Results: Participants reporting RSD were few; 3.1% (Japan), 1.3% (PRC), 2.5% (UK), 7.2% (USA); 15.1, 7.9, 16.7 and 16.8% of people with treated hypertension. For those reporting RSD, 24-h urinary sodium excretion was significantly, but only modestly lower than for others, by 17.9 mmol/day (Japan), 56.7 (PRC) and 14.7 (USA), but higher by 10.5 in UK. Sodium intakes for participants reporting RSD remained higher than recommended; 181.0 mmol/day (Japan), 171.5 (PRC), 155.2 (UK) and 148.9 (USA). For these people, as for others, main sources of salt were processed foods in Japan, UK and USA; in PRC, salt added in preparation at home., Conclusion: Enhanced sustained efforts are needed to raise general awareness of the harmful effects of salt on health and the benefits of salt reduction. Population approaches are needed to reduce salt content of processed foods and restaurant meals.