Effect of salt reduction interventions in lowering blood pressure: A comprehensive systematic review and meta-analysis of controlled clinical trials.

BACKGROUND: Excessive salt intake results in hypertension (HTN), which is a major risk factor for cardiovascular disease (CVD). This review and meta-analysis aimed to evaluate the effect of salt reduction interventions on systolic blood pressure (SBP) and diastolic blood pressure (DBP). METHODS: Studies were identified via systematic searches of the databases, including PubMed, Embase, Scopus, and Web of Science. All the studies examining the effectiveness of salt reduction interventions on blood pressure (BP), regardless of age, sex, and HTN status, were included in the systematic review, and eligible studies were used in the meta-analysis. A random-effect model was applied for quantitative data synthesis. RESULTS: A total of 50 trials extracted from 40 articles (21 trials on nutrition education,10 on self-help materials,17 on salt substitutes, and 2 on food reformulation) were included in the systematic review. The pooled results of 44 eligible trials showed that salt substitution and nutrition education interventions had significant effects on both SBP (WMD: -7.44 mmHg, P<0.001 and WMD: -2.75 mmHg, P<0.001, respectively), and DBP (WMD: -3.77 mmHg, P<0.001 and WMD: -2.11 mmHg, P<0.001, respectively). Furthermore, using self-help materials led to a significant reduction in SBP among subjects aged 25-60 years (WMD: -2.60 mmHg, P = 0.008); it also decreased both SBP and DBP among those who were hypertensive (WMD: -3.87 mmHg, P = 0.003 and WMD: -2.91 mmHg, P<0.001, respectively). CONCLUSION: Our results supported that salt substitution and nutrition education are effective nutrition strategies to lower BP. It seems that multi-component approaches could be more effective in improving BP status. However, further trials are required.

Prioritizing population-based nutrition-related interventions to prevent and control hypertension in Iran: a multi-criteria decision-making approach.

BACKGROUND: Numerous nutrition-related policy options and strategies have been proposed to tackle hypertension and other risk factors of non-communicable diseases (NCDs). In this study, we developed a comparative analysis using a multi-criteria decision-making (MCDM) model for prioritizing population-based nutrition-related interventions to prevent and control hypertension in Iran. METHODS: We employed a combination of Delphi technique and Analytic Hierarchy Process (AHP) method as the methodological tool to prioritize decision alternatives using multiple criteria. The prominent assessment criteria and intervention strategies were derived using a literature review, focus group discussion (n = 11), and a 2-round modified Delphi technique with specialists and experts involved in different stages of health policy-making (round 1: n = 50, round 2: n = 46). Then, the AHP was used to determine the weightage of the selected interventions and develop the decision-making model. The sensitivity analysis was performed to test the stability of the priority ranking. RESULTS: Nine alternative interventions were included in the final ranking based on eight assessment criteria. According to the results, the most priority interventions to prevent and control hypertension included reformulation of food products to contain less salt and changing the target levels of salt in foods and meals, providing low-sodium salt substitutes, and reducing salt intake through the implementation of front-of-package labeling (FOPL). The results of the sensitivity analysis and a comparison analysis suggested that the assessment model performed in this study had an appropriate level of robustness in selecting the best option among the proposed alternatives. CONCLUSION: MCDM techniques offer a potentially valuable approach to rationally structuring the problem, along with the opportunity to make explicit the judgments used as part of the decision-making model. The findings of this study provide a preliminary evidence base to guide future decisions and reforms aiming to improve appropriate population-based interventions for tackling hypertension and other risk factors of NCDs.

Correction: Factors influencing weight management behavior among college students: An application of the Health Belief Model.

[This corrects the article DOI: 10.1371/journal.pone.0228058.].

The impact of L-citrulline supplementation on glucose homeostasis, lipid profile, and some inflammatory factors in overweight and obese patients with type 2 diabetes: A double-blind randomized placebo-controlled trial.

This study investigated the impact of L-citrulline on glucose homeostasis, lipid profile, and inflammatory factors in overweight and obese patients with type 2 diabetes (T2D). In total, 54 participants with T2D were assigned to L-citrulline (3 g/day L-citrulline) or placebo groups and tested for 8 weeks. Serum levels of insulin, fasting glucose, hemoglobin A1c (HbA1c), lipid profile, tumor necrosis factor-α (TNF-α), high-sensitivity C-reactive protein (hs-CRP), and L-citrulline were measured pre- and post-intervention. Totally, 45 patients were enrolled in the research. L-citrulline supplementation decreased serum levels of insulin (p = .025), glucose (p = .032), HbA1c (p = .001), HOMA-IR (p = .037), TNF-α (p = .036), and hs-CRP (p = .027) significantly. At the end of the study, despite the significant decrease in serum levels of triglyceride (p = .027) and the increase in high-density lipoprotein cholesterol levels (p < .001) in the L-citrulline group, no significant differences were found for these parameters between the groups. Moreover, no significant inter- and intra-group changes were observed for dietary intakes, anthropometric indices, total and low-density lipoprotein cholesterol levels (p > .05). In conclusion, L-citrulline supplementation might improve glucose homeostasis, some lipid factors and inflammatory markers in overweight and obese patients with T2D.

Comparison of endocannabinoids levels, FAAH gene polymorphisms, and appetite regulatory substances in women with and without binge eating disorder: a cross- sectional study.

Binge eating disorder (BED) is known as the most common eating disorder with both psychosocial and biological factors involved. In this regard, there is a need to recognize probable disturbances in substances involved in food intake regulation in BED. In this study, we hypothesized that the levels of endocannabinoids, fatty acid amid hydrolase (FAAH) gene polymorphisms, and appetite regulatory substances are different in overweight and obese women with and without BED. A Binge Eating Scale was used to estimate the prevalence of BED in 180 women classified as overweight or obese. The levels of anandamide (AEA), 2-arachidonoylglycerol (2-AG), leptin, insulin, and orexin-A were measured by enzyme-linked immunosorbent assay kits. The subjects were genotyped for polymorphisms of FAAH gene using amplification refractory mutation system-polymerase chain reaction. Data were analyzed using SPSS software. About 41.6% (n = 75) of the subjects were diagnosed with BED. Women with BED exhibited significantly higher levels of AEA, 2-AG, leptin, and insulin compared to non-BED women (P < .05). Binary logistic regression analysis also showed that AEA, leptin, and insulin were the predictors of having BED after adjusting for body mass index (P < .05). In addition, the frequency of A allele of FAAH gene was higher in women with BED compared to women without BED; however, there were no significant differences between these 2 groups (P = .08). These results supported our hypothesis in the cases of AEA, 2-AG, leptin, and insulin but not orexin and FAAH gene polymorphisms. The findings of the current study provide further evidence concerning the role of these substances in BED.

The association of dietary patterns with endocannabinoids levels in overweight and obese women.

BACKGROUND: Higher levels of anandamide (AEA) and 2-arachidonoylglycerol (2-AG), the main arachidonic acid-derived endocannabinoids, are frequently reported in overweight and obese individuals. Recently, endocannabinoids have become a research interest in obesity area regarding their role in food intake. The relationship between dietary patterns and endocannabinoids is poorly understood; therefore, this study evaluated the association of the dietary patterns with AEA and 2-AG levels in overweight and obese women. METHODS: In this cross sectional study, 183 overweight and obese females from Tabriz, Iran who aged between 19 and 50 years old and with mean BMI = 32.44 ± 3.79 kg/m2 were interviewed. The AEA and 2-AG levels were measured, and the dietary patterns were assessed using food frequency questionnaire. To extract the dietary patterns, factor analysis was applied. The association between AEA and 2-AG levels and dietary patterns was analyzed by linear regression. RESULTS: Three major dietary patterns including "Western", "healthy", and "traditional" were extracted. After adjusting for age, physical activity, BMI, waist circumference, and fat mass, higher levels of AEA and 2-AG were observed in participants who were in the highest quintile of the Western pattern (P <  0.05). Also, in both unadjusted and adjusted models, significantly lower levels of AEA and 2-AG were detected in the women of the highest quintile of the healthy pattern (P <  0.01). Moreover, there was no significant association between "traditional" pattern and AEA and 2- AG levels in both unadjusted and adjusted models (P > 0.05). CONCLUSION: In regard with the lower levels of endocannabinoids in healthy dietary pattern, adherence to healthy pattern might have promising results in regulating endocannabinoids levels.

The association of circulating endocannabinoids with appetite regulatory substances in obese women.

BACKGROUNDS: Endocannabinoids especially anadamide (AEA) and 2­arachidonoylglycerol (2-AG) together with appetite modulators have recently been of great importance in body weight regulation and obesity incidence. The present study was carried out to investigate AEA and 2-AG levels and their association with leptin, insulin, orexin - A, and anthropometric indices in obese women. METHODS: The demographic and anthropometric data of 180 overweight/ obese women with mean age 34.2±8.27 years old, and mean BMI 32.54±3.73kg/m2 were evaluated. The plasma levels of anadamide and 2­arachidonoylglycerol levels and also serum levels of leptin, insulin and orexin- A concentrations were measured. Pearson and spearmen correlation tests along with hieratical regression test were used to assess the association of endocannabinoids levels with anthropometric indices and appetite modulators. RESULTS: Significant correlations were revealed between AEA and 2-AG with leptin, BMI, waist circumference (WC) and body fat percent (BF%) (P<0.001). 2-AG levels correlated positively with mean insulin levels (P<0.001). Neither AEA nor 2-AG correlated significantly with serum orexin - A levels. Leptin, insulin, BMI, WC, and BF% were significant independent predictors of AEA and 2-AG in the hierarchical regression model (P<.001) and explained 65% and 68% of variance in AEA and 2-AG respectively (P<0.001). CONCLUSION: The findings showed that levels of AEA and 2-AG were associated with BMI, WC, BF%, and leptin and insulin levels. Also, BMI, WC, BF%, leptin and, insulin levels can have predictive value for determining AEA and 2-AG.

Factors influencing weight management behavior among college students: An application of the Health Belief Model.

BACKGROUND: Overweight and obesity have become a significant public health concern in both developing and developed countries. Due to the health implications of weight-reduction behaviors, it is important to explore the factors that predict their occurrence. Therefore, the present study was performed to examine factors affecting the behavioral intention of weight management as well as assess the predictive power of the Health Belief Model (HBM) for body mass index (BMI). METHODS: This cross-sectional study was conducted among 336 female students recruited from dormitories of Tabriz University of Medical Sciences, using quota sampling technique. Data were collected by a structured questionnaire in seven parts (including perceived severity, perceived susceptibility, perceived benefit, perceived barrier, cue to action, self-efficacy in dieting and physical activity, and behavioral intention of weight management), based on the HBM. Structural equation modeling (SEM) was conducted to identify the relationship between HBM constructs and behavioral intention of weight management. Linear regression model was performed to test the ability of the HBM to predict students' BMIs. RESULTS: Higher level of perceived threats (sum of perceived susceptibility and severity) (ß = 0.41, P<0.001), perceived benefits (ß = 0.19, P = 0.009), self-efficacy in exercise (ß = 0.17, P = 0.001), and self-efficacy in dieting (ß = 0.16, P = 0.025) scales was significantly related to greater behavioral intention of weight management. Moreover, perceived threat mediated the relationships between perceived cue to action, perceived benefits, self-efficacy in exercise, and weight management practices. The fit indices of the SEM model seemed acceptable. The final regression model explained approximately 40% of variance in BMI (P<0.001). Additionally, perceived severity, barrier, and self-efficacy in dietary life were the significant variables to predict students' BMIs. CONCLUSIONS: These findings suggest that health education programs based on the HBM needs to be integrated in preventive health programs and health interventions strategies to ensure adherence and well-being of the participants.

The influence of the fatty acid amide hydrolase 385C>A single nucleotide polymorphisms on obesity susceptibility.

The chronic over-activation of the endogenously produced cannabinoids in obesity has been demonstrated in several studies. A common 385C>A single nucleotide polymorphism of the fatty acid amide hydrolase, one the most important inactivating enzymes of endogenous cannabinoids, has been shown to be associated with obese phenotype. This study was designed to investigate the FAAH gene polymorphisms and to compare the obesity indices between different genotypes in Iranian overweight/obese women. A total of 180 healthy overweight/obese subjects (BMI = 25 to 40 kg/m2) and 86 normal weight individuals (BMI = 18.5 to 24.9 kg/m2) were genotyped for 385 C/A polymorphism of FAAH using amplification refractory mutation system (ARMS)-PCR. Anthropometric indices including BMI, waist circumference, neck circumference, waist to height ratio, fat mass were evaluated. A written informed consent form was given by the participants. The genotype and allele frequencies were significantly different between the overweight/obese and control groups (P = 0.04). Significant differences were observed between the CC genotype and the AA+CA genotype regarding the anthropometric indices (P < 0.05). Compared to CC group, a higher BMI, WC, WHtR, NC and fat mass was identified in allele A carriers group. After adjusting for age, marital and physical activity status, it was revealed that having the CA/AA genotype increased the probability of obesity risk almost two times (P < 0.05, 95% CI 1.19-3.67). Our findings showed that the frequency of A allele was greater in overweight/obese individuals. Also, a mutation in FAAH gene was associated with higher anthropometric indices and the CA/AA genotype increased significantly the possibility of being obese in Iranian women.

Does Maternal Synbiotic Supplementation Affect Conjugated Linoleic Acid Level in Breast Milk? A Randomized Placebo-Controlled Clinical Trial.

AIM: As conjugated linoleic acid (CLA)is a potential growth promotor in newborns, the present pilot study aimed at measuring the effect of synbiotic supplementation on breast milk CLA level. MATERIALS AND METHODS: Sixty lactating mothers were randomly allocated to take either synbiotic (n = 31) or placebo (n = 29) for 30 days. Maternal anthropometric indices were measured at the onset and end of the study by standard methods and body mass index was calculated. Information on food intake was collected by using a 24 hours 24-hour recall method for 2 days and food record questionnaire for 1 day. Breast milk lipids were extracted and CLA level was quantified by gas chromatography. RESULTS: No significant differences were observed in the baseline mean breast milk concentrations of Fatty acids (FAs) between the synbiotic and placebo groups (p > 0.05). The CLA content of breast milk increased significantly by 58% (from 0.19 ± 0.15 to 0.30 ± 0.22 mmol/L) in the supplemented group, whereas it decrease decreased slightly but not significantly by 14% (from 0.22 ± 0.14 to 0.19 ± 0.10 mmol/L) in the placebo group. After adjustment for covariates, the CLA content of breast milk was significantly higher in the supplemented group compared with placebo group after the intervention (p = 0.03). The ratio of total n - 6:3 increased significantly over time in both groups, but was not different among groups (p < 0.05). CONCLUSIONS: This pilot study showed that supplementation of lactating women with synbiotic, resulted in increased breast milk CLA composition. Further research using different species of probiotic bacteria and analysis of maternal and infant plasma FAs would be beneficial.

Accuracy of the Common Predictive Equations for Estimating Resting Energy Expenditure among Normal and Overweight Girl University Students.

OBJECTIVE: The aim of the present study was to determine the accuracy of commonly used predictive formulas of resting metabolic rate (RMR) compared to measured RMR in normal and overweight young females. METHODS: In this cross-sectional study, 98 female university students aged 18-30 years with body mass index 18 to 30 kg/m(2) were recruited. Anthropometric indices and body compositions were measured. RMR was measured by indirect calorimetry (FitMate, Cosmed, Rome, Italy) and estimated by 11 predictive formulas. The accuracy of the RMR formulas and mean percentage differences between estimated and measured values were calculated. Paired t test was used to compare estimated and measured RMRs. RESULT: There were no significant differences between measured and estimated RMR by the 4 commonly used formulas (Mifflin, Cunningham, and World Health Organization [WHO]/Food and Agriculture Organization [FAO]). Among all of the equations, the Mifflin formula showed the lowest bias (-2.97 ± 116.43 kcal/day) at the group level and was the most accurate formula (80.23%) in normal and overweight participants. The over- and underestimated values were about 14% and 5.5%, respectively. In normal and overweight females, Mifflin was the most accurate formula, with 75.51% and 84.61% accuracy, respectively. CONCLUSION: Given the current lack of a standardized formula that consistently delivers accurate results, the Mifflin formula can be recommended for estimating energy requirements in normal and overweight females in clinical practice.

Comparison of Indirect Calorimetry and Predictive Equations in Estimating Resting Metabolic Rate in Underweight Females.

BACKGROUND: Underweight as a public health problem in young women is associated with nutritional deficiencies, menstrual irregularity, eating disorders, reduced fertility, etc. Since resting metabolic rate (RMR) is a necessary component in the development of nutrition support therapy, therefore we determined the accuracy of commonly used predictive equations against RMR measured by indirect calorimetry among healthy young underweight females. METHODS: This cross-sectional study was conducted on 104 underweight females aged 18-30 years old with body mass index (BMI) <18.5 kg/m(2) in 2013. After collecting anthropometric data, body composition was measured by bioelectric impedance analysis (BIA). RMR was measured by using indirect calorimetry (FitMate™) and was estimated by 10 commonly used predictive equations. Comparisons were conducted using paired t-test. The accuracy of the RMR equations was evaluated on the basis of the percentage of subjects' predicted RMR within 10% of measured RMR. RESULTS: The mean BMI of subjects was 17.3±1.3 kg/m(2). The measured RMR ranged 736-1490 kcal/day (mean 1084.7±175 kcal/day). Findings indicated that except Muller and Abbreviation, other equations significantly over estimated RMR, compared to measured value (P<0.05). As an individual prediction accuracy, these predictive equations showed poor performance with the highest accuracy rate of 54.8% for Muller equation (22.1% under and 23.1% over-prediction) and 43.3% for Abbreviation equation (31.7% under and 25% over-prediction), the percentage bias was 1.8% and 0.63% and RMSE was 162 and 173 kcal/d, respectively. CONCLUSION: Although Muller equation gave fairly acceptable prediction, more suitable new equations are needed to be developed to help better management of nutritional plans in young underweight people.