Relationship between dietary factors and the number of altered metabolic syndrome components in Chinese adults: a cross-sectional study using data from the China Health and Nutrition Survey

Association between urbanization and metabolic syndrome in low- and middle-income countries: A systematic review and meta-analysis

AIMS

The prevalence of metabolic syndrome (MetS) is on the rise in an increasingly urbanized world. The study aimed to review the association between urbanization and MetS in low- and middle-income countries (LMICs).

DATA SYNTHESIS

A comprehensive search of five databases (MEDLINE, Web of Science, Scopus, EMBASE, and CENTRAL) was performed in January 2022 and updated in October 2022. Peer-reviewed studies that met the eligibility selection criteria were included. Search terms were used for the main concepts which are MetS, dietary patterns, and urbanization in LMICs. Study selection was done in two stages and in duplicate. Random effects models were used to calculate the overall pooled prevalence and main study-level characteristics. Out of 9,773 identified studies, nineteen were included in the systematic review and meta-analysis. The studies were done on 313,644 participants (149,616 urban and 164,028 rural). The pooled risk ratio (RR, 95% confidence interval) of MetS between urban and rural dwellers was RR = 1.24; 95%CI [1.15, 1.34] (I2 = 96.0%, P < 0.0001). A relatively higher prevalence of MetS among urban than rural residents has been observed, especially with the International Diabetes Federation criteria (RR = 1.54; 95%CI [1.21, 1.96]; I2 = 65.0%), and in the population in India (RR = 2.19; 95%CI = 1.24, 3.88, I2 = 85%). Overall, the role of dietary patterns in the development of MetS was inconsistent, and few studies showed a lower risk of MetS with adherence to recommended healthy dietary patterns.

CONCLUSIONS

There was an association between urbanization and the high prevalence of MetS. Interventions and policies to reduce the risk of MetS are needed.

Metabolic syndromes increase significantly with the accumulation of bad dietary habits

BACKGROUND

The association between dietary habits and metabolic syndrome (MetS) has not been well documented, due to the complexity and individualization of dietary culture in the Chinese population.

OBJECTIVE

To construct a composite score from various bad dietary habits and to evaluate their comprehensive association with the prevalence of MetS and its components among Chinese men and women across various age groups.

SETTING

Serial cross-sectional studies.

METHODS

Twenty-three dietary habits were assessed through face-to-face interviews with 98,838 males and 83,099 females in health check-up programs from 2015 to 2021, among which eighteen bad dietary habits were observed to be associated independently with total MetS. The total score of bad dietary habits was composed of four categories via variable clustering analysis, including irregular dietary habits, unhealthy dietary flavors, unbalanced dietary structure, and high-fat diet. The 2016 Chinese guideline for the management of dyslipidemia in adults was used to define MetS.

RESULTS

Men had a higher score of bad dietary habits than women (9.63 ± 3.11 vs. 8.37 ± 3.23), which decreased significantly with increasing age in both males and females (Pinteraction<0.01). The prevalence of total MetS increased significantly with the cumulative score of bad dietary habits in both males (highest quintile vs. lowest quintile: OR, 1.90; 95% confidence interval [CI], 1.80-2.00; Plinear<0.01) and females (OR, 2.23; 95% CI, 2.02-2.46; Plinear<0.01) after adjusted for age, education, smoking status, alcohol consumption, and physical activities. These linear trends were also observed for each MetS component (all Plinear<0.01). The role of irregular dietary habits and high-fat diet on MetS prevalence are much higher in males than in females, while unhealthy dietary flavors and unbalanced dietary structure had a greater influence on females.

CONCLUSIONS

The accumulation of bad dietary habits contributes to the MetS developments. Thus, individualized lifestyle interventions are needed to correct bad dietary habits with regard to gender differences.

Dairy consumption in adults in China: a systematic review

BACKGROUND

Research on dairy consumption in China is lacking, however, some evidence has demonstrated significant changes in recent years, with a reported increase in the overall consumption of dairy products. To fully understand these changes, a systematic review was conducted to examine reported dairy intakes and differences between dairy consumption in different population groups in China.

METHODS

Web of Science, Embase, and PubMed databases were searched for studies published from January 2000 to September 2022. The China National Knowledge Infrastructure (CNKI) was used to retrieve papers available in Chinese. Papers reporting dietary intakes of dairy consumption across age, sex, and geographical location sub-groups were considered for inclusion in this review. In addition, this review includes the consumption of different types of dairy foods and changes in dairy intake over time.

RESULTS

Forty-seven papers were included in the present study. Twelve papers examined dairy consumption across age groups, showing that middle-aged adults tend to consume less dairy than other age groups. Studies comparing across location-specific cohorts reported dairy intakes among urban populations were higher than rural, as well as being higher than the national average. Coastal, Northern and Eastern residents consumed more dairy products than those living in other regions of China, and people in larger cities had higher reported intakes than smaller cities. Milk was the primary dairy product reportedly consumed by Chinese population, followed by yogurt. Concerning sex, evidence showed that females generally reported a greater daily dairy intake than males.

CONCLUSIONS

This review shows that, in China, several different population groups displayed significant differences in the amount and type of dairy consumed. When considering the incorporation of dairy products into healthy eating guidelines or positioning specific dairy products on the market, it is important to consider the differences and variations in consumption patterns within population groups.

The Effect of Dietary Pattern on Metabolic Syndrome in a Suburban Population in Shanghai, China

Metabolic syndrome (MetS) is recognized as one of the most severe non-communicable chronic diseases. Diet plays an essential role in the development and exacerbation of MetS. Thus, this study aimed to investigate the relationship between dietary patterns and MetS in a suburban population in Shanghai, China. Data were collected on the Zhongshan community from the Shanghai Suburban Adult Cohort and Biobank (SSACB) study between May and September 2017. A total of 5426 participants who completed the questionnaire investigation, physical measurements, and biological sample collection were effectively enrolled in this study. Both posteriori and priori methods were utilized to generate different dietary patterns, including the dietary approaches to stop hypertension (DASH) and Mediterranean diet (MD). The prevalence of MetS in this study was 22.47%. Compared to the reference, dietary patterns with a higher intake of "dairy and fruits" and "coarse cereals and soy products" had protective effects on MetS (p < 0.05). However, no significant correlation with MetS was observed for DASH and MD. Our study recommends higher consumption of fruits, coarse cereals, and soy products, which was associated with a lower prevalence of MetS in the suburban population of Shanghai. The correlation of DASH and MD with MetS in the Chinese population requires further exploration.

Impact of urinary sodium excretion on the prevalence and incidence of metabolic syndrome: a population-based study

OBJECTIVE

To evaluate the association of metabolic syndrome (MetS) risk with 24-hour urinary sodium excretion (24hUNaE) estimated from spot urine samples.

DESIGN

Serial cross-sectional studies were conducted, and those with multiple repeated examinations were used to assess the MetS incidence risk.

SETTING AND PARTICIPANTS

A health check-up programme was conducted between 2018 and 2021 and enrolled 59 292 participants to evaluate the relationship between MetS risk and 24hUNaE in the Third Xiangya Hospital, Changsha, China. Among these participants, 9550 had at least two physical examinations during this period, which were used to evaluate the association of a new occurrence of MetS with 24hUNaE.

OUTCOMES

Guidelines for the prevention and treatment of dyslipidaemia in Chinese adults (revised in 2016) were used to define prevalent and incident MetS.

RESULTS

The prevalence of MetS was 19.3% at the first check-up; among individuals aged ≤55 years, the risk was higher in men than women, while among older individuals, a similar prevalence was observed in both sexes. A significant increase in MetS prevalence was observed per unit increase in 24hUNaE (adjusted OR (AOR) 1.11; 95% CI 1.09 to 1.13), especially for the prevalence of central obesity and elevated blood pressure. Additionally, 27.4% of the participants among the 7842 participants without MetS at the first check-up (male vs female: 37.3% vs 12.9%) were found to have a new occurrence of MetS at the second, third and/or fourth check-ups. A 25% increase in MetS incidence was observed per unit increase in 24hUNaE (95% CI 1.19 to 1.32), which was more prominent in the participants with a new occurrence of central obesity and elevated fasting blood glucose.

CONCLUSIONS

Although the prevalence of MetS seemed stable, new occurrences of MetS remained high, which might result in MetS recurrence. The influence of sodium intake on MetS development is probably attributed to the increase in blood pressure and central obesity, but a new occurrence of MetS may develop through elevated blood glucose and central obesity.

Modifiable factors of 20-year blood pressure trajectories among normotensives and their associations with hypertension : a prospective study

Little is known about the impact of modifiable risk factors on blood pressure (BP) trajectories and their associations with hypertension (HTN). We aimed to identify BP trajectories in normotensive Chinese adults and explore their influencing factors and associations with HTN. We used data from 3436 adults with at least four BP measurements between 1989 and 2018 in the China Health and Nutrition Survey, an ongoing cohort study. We measured BP using mercury sphygmomanometers with appropriate cuff sizes in all surveys. We used group-based trajectory modelling to identify BP trajectories between 1989 and 2009 and multiple logistic and Cox regression models to analyse their influencing factors and associations with HTN in 2011-2018. We identified five systolic blood pressure (SBP) trajectories, 'Low-increasing (LI)', 'Low-stable (LS)', 'Moderate-increasing (MI)', 'High-stable (HS)' and 'Moderate-decreasing (MD)', and four diastolic blood pressure (DBP) trajectories classified as 'Low-increasing (LI)', 'Moderate-stable (MS)', 'Low-stable (LS)' and 'High-increasing (HI)'. People with higher physical activity (PA) levels and lower waist circumferences (WC) were less likely to be in the SBP LI, MI, HS and MD groups (P < 0·05). People with higher fruit and vegetable intakes, lower WCs and salt intakes and higher PA levels were less likely to be in the DBP LI, MS and HI groups (P < 0·05). Participants in the SBP HS group (hazard ratio (HR) 2·01) or the DBP LI, MS and HI groups (HR 1·38, 1·40, 1·71, respectively) had higher risks of HTN (P < 0·05). This study suggests that BP monitoring is necessary to prevent HTN in the Chinese population.

Lifestyle behaviors, metabolic disturbances, and weight gain in psychiatric inpatients treated with weight gain-associated medication

Many psychiatric patients suffer from overweight/obesity and subsequent metabolic disturbances, where psychotropic medication is one of the main contributors. However, the magnitude of weight gain ranges individually, which leads to questioning the role of other contributors like lifestyle factors. The present study investigated several lifestyle factors among psychiatric inpatients, their relation to biological factors, and their predictive capability for weight gain during treatment. Using a naturalistic observational study design, psychiatric inpatients of all diagnoses were followed for 4 weeks from the start of treatment with weight gain-associated medication. N = 163 participants entered the study. Lifestyle factors were assessed by patient self-report questionnaires. Body weight change over time was calculated relative to baseline body weight. Our study provides three main findings: (1) Obesity and/or metabolic syndrome (metSy) were associated with emotional eating (disinhibition), craving for fast food and sweets, and weight cycling. (2) Patients without metSy and normal BMI experienced increased sweets craving (also for women), a more positive attitude towards drugs, and an improvement of affect (also for men). (3) Sex, presence of metSy and/or drug dosage interacted with disinhibition change, sweets craving change (trend), and fast food craving change to predict weight change over time. Furthermore, drug attitude change interacted with BMI, drug dosage, and presence of metSy to predict weight change. Lifestyle factors, especially eating behaviors, are related to metabolic disturbances and predict weight gain in interaction with clinical parameters.

The Effects of Dietary Pattern on Metabolic Syndrome in Jiangsu Province of China: Based on a Nutrition and Diet Investigation Project in Jiangsu Province

Metabolic syndrome, a complex group of metabolic disorders of energy use and storage, is considered as an important determinant risk factor for many cardiovascular diseases. This study aimed to examine the association between metabolic syndrome (MetS) and dietary pattern among adults in Jiangsu Province of China. Data were from three rounds of cross-sectional nutrition and diet investigation projects in Jiangsu Province of China, which were conducted in 2002, 2007, and 2014 by Jiangsu Provincial Center for Disease Control and Prevention. A total of 13,944 participants with complete food frequency questionnaire (FFQ) were eventually included in this study after further data screening. The 2009 Joint Interim Statement for China was used to define metabolic syndrome. Three distinct dietary patterns were identified by factor analysis: the modern dietary pattern (rich in pork, poultry, vegetables, seafood, pastry food, other animal meats, fruits, milk and its products, soft drink, whole grains, nuts, and seeds, but low in wheat), vegetable oils/condiments/soy products dietary pattern (rich in vegetable oils, other condiments, salt, soy products, and fruits and low in dry legumes), and modern high-wheat dietary pattern (rich in wheat, tubers, fruits, and other animal meats, but low in rice). Higher intake of the modern dietary pattern and modern high-wheat dietary pattern were positively associated with metabolic syndrome in both unadjusted and adjusted models by genders, whereas higher intake of the vegetable oils/condiments/soy products dietary pattern had a negative relationship with metabolic syndrome in both unadjusted and adjusted models by genders (p < 0.05). Our study recommends reducing the consumption of animal meat products, especially processed meat products, and replacing animal oils with vegetable oils as the main supply of daily oils. Furthermore, more prospective and experimental studies are needed to confirm the relationship between dietary patterns and metabolic syndrome.

Reduced plasma carotenoids in individuals suffering from metabolic diseases with disturbances in lipid metabolism: a systematic review and meta-analysis of observational studies

This review summarises the association between serum carotenoids, serum retinoids and dietary intake outcomes with obesity/overweight and individuals with metabolic diseases with disturbances in lipid metabolism. Observational studies reporting dietary intakes and serum concentrations of carotenoids and retinol were collected from Medline and Web of Science. Mean differences were calculated between "cases" (classified as obese, overweight or having a metabolic disease with disturbances in lipid metabolism; i.e. non-alcoholic fatty liver disease, type 2 diabetes, dyslipidaemia or metabolic syndrome) and "comparator group" (classified as normal weight healthy individuals) and summarised in meta-analyses. Significant summary measures were observed for most serum provitamin A and non-provitamin A carotenoids. Studies reporting total serum carotenoids had shown the greatest decrease (-0.28 µmol/l [-0.33, -0.23], p<.001, I²=62.5%, n = 7). There were no significant summary measures for dietary outcomes, suggesting a physiological role of low serum carotenoids in the development of obesity and associated diseases.

Risk of metabolic syndrome and metabolic phenotypes in relation to biomarker-calibrated estimates of energy and protein intakes: an investigation from the Women's Health Initiative

BACKGROUND

Metabolic syndrome (MetS) is associated with increased mortality independent of BMI, resulting in discordant metabolic phenotypes, such as metabolically healthy obese and metabolically unhealthy normal-weight individuals. Studies investigating dietary intake in MetS have reported mixed results, due in part to the limitations of self-reported measures.

OBJECTIVES

To investigate the role of biomarker-calibrated estimates of energy and protein in MetS and metabolic phenotypes.

METHODS

Postmenopausal participants from the Women's Health Initiative (WHI) study who were free of MetS at baseline, had available data from FFQs at baseline, and had components of MetS at Year 3 (n = 3963) were included. Dietary energy and protein intakes were estimated using biomarker calibration methods. MetS was defined as 3 or more of the following: elevated serum triglycerides (≥150 mg/dL), low HDL cholesterol (<50 mg/dL), hypertension [systolic blood pressure (BP) ≥130 or diastolic BP ≥85 mmHg], elevated serum glucose (>100 mg/dL), and abdominal adiposity (waist circumference > 89 cm). Models were adjusted for age, WHI study component, race/ethnicity, education, income, smoking, recreational physical activity, disease history, and parity.

RESULTS

For every 10% increment in total calibrated energy intake, women were at a 1.37-fold elevated risk of MetS (95% CI, 1.15-1.63); a 10% increment in calibrated total protein intake was associated with a 1.21-fold elevated risk of MetS (95% CI, 1.00-1.47). Specifically, animal protein intake was associated with MetS (OR, 1.08; 95% CI, 1.02-1.14), whereas vegetable protein intake was not (OR, 0.99; 95% CI, 0.95-1.03). No differences were seen when examining metabolic phenotypes.

CONCLUSIONS

We found that higher calibrated total energy, total protein, and total animal protein intakes were strongly associated with MetS. If replicated in clinical trials, these results will have implications for the promotion of energy and animal protein restrictions for the reduction of MetS risks.

Association of dietary patterns and practices on metabolic syndrome in adults with central obesity attending a mission hospital in Kenya: a cross-sectional study

OBJECTIVE

Dietary patterns and practices can predispose or protect against metabolic syndrome (MetS) in humans. Despite the growing problem of MetS in adults, the underpinning dietary behaviour is poorly understood. We determined the dietary patterns and practices relevant to MetS in adults with central obesity attending a mission hospital in Kenya.

STUDY DESIGN

Descriptive, cross-sectional.

SETTING

Outpatient clinic of a mission-based hospital in Nairobi.

PARTICIPANTS

Adults (N=404) aged 18-64 years diagnosed with central obesity as per the International Diabetes Federation definition for MetS.

PRIMARY OUTCOMES

Anthropometric measurements, clinical-biochemical markers and dietary components, quantity and frequency of food intake, as well as time-lapse between consumption of dinner and sleeping.

RESULTS

A high (87.2%) prevalence of MetS was observed for respondents who reported consumption of large amount of carbohydrates (p<0.001), proteins (p<0.001), processed/fast foods (p<0.001) and sugar (p=0.009). Frequent consumption of legumes (p<0.001), nuts (p<0.001), fruits (p<0.001) and vegetables (p=0.021) was linked to reduced MetS. Additionally, longer interval between eating dinner and going to bed was associated with reduced MetS.

CONCLUSION

Regular consumption of fruits, vegetables, legumes and nuts, as well as observing sometime after eating dinner before sleeping, was the dietary pattern significantly associated with a lower risk of MetS. Whereas, consumption of a large quantity of carbohydrates, proteins, processed/fast foods and sugar is likely to predispose to MetS. The findings underscore the need to focus on specific dietary intake patterns including frequency, quantity, quality and variety for MetS prevention and management. The MetS-related interventions could be implemented during individual consultation, group and community health messaging sessions.

Gender Differences in the Pattern of Socio-Demographics Relevant to Metabolic Syndrome Among Kenyan Adults with Central Obesity at a Mission Hospital in Nairobi, Kenya

INTRODUCTION

Metabolic syndrome (MetS) is a risk factor for cardiovascular-related morbidity and mortality. Although the risk factors for MetS are well documented, differences in gender-based demographics among Kenyan adults with central obesity are lacking.

AIM

Determine gender differences in the pattern of socio-demographics relevant to metabolic syndrome among Kenyan adults with central obesity at a mission hospital, Nairobi.

METHODS

A cross-sectional baseline survey involving adults (N = 404) with central obesity aged 18-64 years, as part of a community-based lifestyle intervention study. Respondents were systematically sampled using the International Diabetes Federation definition for MetS. Lifestyle characteristics, anthropometric, clinical and biochemical markers were measured and analyzed using SPSS.

RESULTS

High (87.2%) MetS prevalence associated with advanced age in males (p < 0.001) and females (p = 0.002) was observed. MetS was likely among divorced/separated/widowed (p = 0.021) and high income males (p = 0.002) and females (p = 0.017) with high income. Unemployed males (p = 0.008) and females with tertiary education (p = 0.019) were less likely to have MetS. Advanced age was likely to lead to high blood pressure, fasting blood glucose and triglycerides (p < 0.05). Males were more likely (p = 0.026) to have raised triglycerides, while females (p < 0.001) had low high density lipoproteins.

CONCLUSION

A high prevalence of MetS associated with social and gender differences among Kenyan adults with central obesity. These underscore the need to look beyond the behavioral and biological risks and focus on every nuance of gender differences in addressing MetS and CVDs.

The association between milk consumption and the metabolic syndrome: a cross-sectional study of the residents of Suzhou, China and a meta-analysis

The association between milk consumption and the metabolic syndrome remains inconclusive, and data from Chinese populations are scarce. We conducted a cross-sectional study to investigate the association between milk consumption and the metabolic syndrome and its components among the residents of Suzhou Industrial Park, Suzhou, China. A total of 5149 participants were included in the final analysis. A logistic regression model was applied to estimate the OR and 95 % CI for the prevalence of the metabolic syndrome and its components according to milk consumption. In addition, the results of our study were further meta-analysed with other published observational studies to quantify the association between the highest v. lowest categories of milk consumption and the metabolic syndrome and its components. There was no significant difference in the odds of having the metabolic syndrome between milk consumers and non-milk consumers (OR 0·86, 95 % CI 0·73, 1·01). However, milk consumers had lower odds of having elevated waist circumference (OR 0·78, 95 % CI 0·67, 0·92), elevated TAG (OR 0·83, 95 % CI 0·70, 0·99) and elevated blood pressure (OR 0·85, 95 % CI 0·73, 0·99). When the results were pooled together with other published studies, higher milk consumption was inversely associated with the risk of the metabolic syndrome (relative risk 0·80, 95 % CI 0·72, 0·88) and its components (except elevated fasting blood glucose); however, these results should be treated with caution as high heterogeneity was observed. In summary, the currently available evidence from observational studies suggests that higher milk consumption may be inversely associated with the metabolic syndrome.

Reduced Insulin Resistance Partly Mediated the Association of High Dietary Magnesium Intake with Less Metabolic Syndrome in a Large Chinese Population

PURPOSE

High dietary magnesium intake may reduce insulin resistance (IR) and metabolic syndrome (MetS). The aim of the cross-sectional analysis was to evaluate the association between dietary magnesium intake, IR, and MetS using data from China Health and Nutrition Survey.

METHODS

Dietary magnesium intake was defined as daily dietary magnesium intake divided by body weight. Logistic regression analysis was used to calculate the odds ratio (OR) for IR and the prevalence of MetS across the quartile categories of dietary magnesium intake. In addition, we used the macro PROCESS to perform the mediation analyses.

RESULTS

A total of 8120 participants were included in the final analysis. We found a significant negative association between dietary magnesium intake and IR, the multivariable-adjusted OR for HOMA-IR comparing the highest to the lowest quartile of dietary magnesium intake was 0.435 (95% confidence intervals [CI] 0.376 to 0.502). The prevalence of the MetS was 38.6%, 28.9%, 22.5%, and 16.5% for increasing quartiles of dietary magnesium intake (p <0.001). The mediation model analysis displayed that insulin resistance mediated the effect of dietary magnesium on MetS. The direct effect and indirect effect of dietary magnesium on MetS were found significant, and the calculated percentage of mediation by insulin resistance was 19.6%.

CONCLUSION

Our study demonstrated a significant and independent negative relationship among weight-adjusted dietary magnesium intake, HOMA-IR, and MetS in a large Chinese population. IR partly mediated the relationship between dietary magnesium intake and MetS.

The Study of Clustering Effects of Behavior Risk Factors in Patients with Metabolic Syndrome in Southern China: A Cross-Sectional Study

OBJECTIVES

Metabolic syndrome (MetS) is now becoming a serious public health threat. Some behaviors risk factors were considered to be associated with MetS and interacted to adversely affect MetS. However, the clustering effects of behavior risk factors of MetS among Chinese population remain unclear. The aim of this study is to observe the behavior risk factors and their clustering effects of MetS in China.

METHODS

A cross-sectional study design was used. Subjects were recruited in the departments of Cardiology Clinic, Endocrine Clinic, and Health Management from March to December 2019. A demographic sheet was designed to collect the demographic and clinical characteristics of the subjects. International Physical Activity Questionnaire-Short was applied to evaluate the level of PA in this study. Other behavior risk factors were observed by the questionnaire. The stepwise logistic regression analysis was performed to identify the determinants of MetS. The multiple logistic regression analysis was used to analyze the clustering effects of behavior risk factors in MetS.

RESULTS

There are a total of 532 eligible subjects (56.6% females; mean age was 48.4 ± 15.3 years), and approximately 33.3% were diagnosed as MetS. The subjects with a smoking habit (heavy and long-time history) had a 1.833-fold higher risk for MetS than their counterparts (none and light smoking), and the subjects that preferred salty taste had a 1.626-fold higher risk for MetS than the comparison cohort. Smoking and alcohol drinking had the highest clustering effect on MetS among the behavior risk factors.

CONCLUSIONS

The main finding of this study was that smoking and salty taste preference were the independent determinants of MetS. Smoking and alcohol consumption had the highest clustering effect on southern Chinese MetS.

Dietary sodium and potassium and risk of diabetes: A prospective study using data from the China Health and Nutrition Survey

AIMS

Dietary sodium and potassium intakes are well-known risk factors for cardiovascular outcomes. However, the associations between dietary sodium and potassium and diabetes are still controversial. Our study aimed to examine whether dietary sodium, potassium and the sodium-potassium ratio are associated with the risk of diabetes, based on a large sample of Chinese adults.

METHODS

The study data were from the 2004-2009 China Health and Nutrition Survey (CHNS), and 5867 participants were eligible for analysis. Sodium and potassium intakes were estimated based on three consecutive 24-h recalls at an individual level combined with a food inventory at a household level performed over the same 3-day period. Diabetes was defined as fasting glucose ≥7.0mmol/L (≥126mg/dL), HbA_1c ≥6.5% or use of antidiabetic drugs.

RESULTS

Over a mean follow-up of 4.7 years, there were 611 (10.4%) incident cases of diabetes. Participants in the higher quartiles (Q3 and Q4) of sodium intake had significantly higher risks of diabetes than those with the lowest sodium intake [Q3, RR: 1.41, 95% CI: 1.06-1.86 and Q4, RR: 1.35, 95% CI: 1.02-1.80; P<0.001 for trend]. In addition, high sodium intakes were significantly associated with levels of fasting glucose and HbA_1c (P<0.05 for trend), with similar associations also found with sodium-potassium ratios (P<0.05 for trend), but not for potassium intakes.

CONCLUSION

This study found that higher sodium intakes and sodium-potassium ratios were significantly associated with a higher risk of diabetes. Further clinical research is now necessary to confirm these results.

Effects of urbanization on metabolic syndrome via dietary intake and physical activity in Chinese adults: Multilevel mediation analysis with latent centering

RATIONALE

China has undergone rapid urbanization in the past decades. Metabolic syndrome refers to a cluster of cardiometabolic risk factors such as abdominal obesity, raised blood pressure, and elevated glucose. Existing studies have not explicitly examined the urbanization effect on metabolic syndrome.

OBJECTIVE

The present study aims to examine the temporal effects of urbanization on metabolic syndrome in the Chinese context and evaluate dietary intake and physical activity as potential mediating factors.

METHOD

The study sample comprised 6,217 Chinese adults aged between 30 and 65 recruited in 218 communities from 2000 to 2009 waves of the China Health and Nutrition Survey. Growth in urbanization of the communities was derived using latent growth modeling on continuous urbanization index from 2000 to 2009. The participants reported their physical activity and dietary intake. Body mass index and biomarkers were measured at 2009 for diagnosis of metabolic syndrome. Multilevel mediation analysis with novel latent centering approach was conducted across gender to evaluate direct and indirect effects of urbanization on metabolic syndrome via changes in dietary intake and physical activity.

RESULTS

The sample displayed linear increasing trends in urbanization, intakes of red meat, dairy products and fast food and declining cereal intake and physical activity with significant inter-individual variations. Controlling for individual-level and community-level covariates, urbanization showed a positive but non-significant direct effect on metabolic syndrome across gender. There were significant and positive indirect effects from urbanization to metabolic syndrome via changes in physical activity in males and via changes in fast food intake in females.

CONCLUSIONS

The present results highlight the health impact of urbanization as a dynamic process at the community level on metabolic syndrome via different indirect pathways of lifestyle factors across gender. Methodological and practical implications are discussed in relation to these modifiable lifestyle factors in the urbanizing Chinese society.

Dietary protein and changes in markers of cardiometabolic health across 20 years of follow-up in middle-aged Americans

OBJECTIVE

Dietary protein plays a role in counteracting age-related muscle loss. However, limited long-term data exist on protein intake and markers of cardiometabolic health, which tend to deteriorate with age.

DESIGN

Prospective cohort study. FFQ-derived protein intake (g/d) and cardiometabolic markers were assessed up to five times across 20 years. Markers included systolic (SBP) and diastolic (DBP) blood pressures, circulating lipids (total, HDL and LDL cholesterol; TAG), estimated glomerular filtration rate (eGFR), fasting glucose (FG), weight and waist circumference (WC). Mixed models accounting for repeated measures were used to estimate adjusted mean annualized changes in outcomes per quartile category of protein.

SETTING

Framingham Heart Study Offspring cohort, USA.

SUBJECTS

Participants (n 3066) with 12 333 unique observations, baseline (mean (sd)) age=54·0 (9·7) years, BMI=27·4 (4·9) kg/m2, 53·5 % female.

RESULTS

In fully adjusted models, there were favourable associations (mean (se)) of total protein with annualized changes in SBP (lowest v. highest intake: 0·34 (0·06) v. 0·04 (0·06) mmHg, P trend=0·001) and eGFR (-1·03 (0·06) v. -0·87 (0·05) ml/min per 1·73 m2, P trend=0·046), unfavourable associations with changes in FG (0·013 (0·004) v. 0·028 (0·004) mmol/l, P trend=0·004) and no associations with weight, WC, DBP or lipids. Animal protein was favourably associated with SBP and unfavourably with FG and WC; plant protein was favourably associated with FG and WC.

CONCLUSIONS

The present study provides evidence that protein intake may influence changes in cardiometabolic health independent of change in weight in healthy adults and that protein's role in cardiometabolic health may depend on the protein source.

Association between Dietary Inflammatory Index, C-Reactive Protein and Metabolic Syndrome: A Cross-Sectional Study

Increased prevalence of metabolic syndrome (MetS) has become a global major public health problem. Chronic low-grade inflammation associated with diet was found to play an import role in the development of MetS, although further studies are needed. The main purpose of this study was to explore the association between the dietary inflammatory index (DII), C-reactive protein (CRP) as a sign of inflammation status, and MetS. A total of 1712 participants from eight cities in China were included. Sociodemographic and health-related information was collected by a self-administrated questionnaire. Anthropometric information and fasting blood samples were collected for identification of MetS. DII scores were computed based on one time 24-h dietary recall. No significant association between MetS and DII was observed except for the blood pressure component of MetS (OR _{T3 versus T1} = 1.40; 95% CI: 1.03 to 1.89). A significant increased prevalence for MetS was observed for higher CRP (OR = 1.66; 95% CI: 1.26 to 2.18), as well as four out of five of MetS components. In stratified analyses by sex, the associations between DII/CRP and MetS among women, but not men, are comparable to the whole sample. In addition, Both the 2nd and 3rd tertile of the DII had a higher CRP level (β-Coefficients _{T2 versus T1} = 0.086, 95% CI: 0.004 to 0.167; β-Coefficients _{T3 versus T1} = 0.145, 95% CI: 0.045 to 0.245) among subjects with MetS. Participants with higher DII scores reported a higher degree of “Shanghuo” (p = 0.007), which is a traditional concept characterized by “redness, swelling, fever and pain” in Chinese Medicine. This study suggested a close association between CRP and MetS, while the association between the DII and MetS was limited. DII was only specifically associated with CRP at a higher level among participants with MetS.