Effect of Low-Fat Diet on Depression Score in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials.

CONTEXT: Current evidence on the effect of a low-fat (LF) diet on depression scores has been inconsistent. OBJECTIVE: To explore the effect of an LF diet on depression scores of adults by systematic review and meta-analysis of randomized controlled trials (RCTs). DATA SOURCES: The PubMed, ISI Web of Science, Scopus, and CENTRAL databases were searched from inception to June 7, 2023, to identify trials investigating the effect of an LF diet (fat intake ≤30% of energy intake) on the depression score. DATA EXTRACTION: Random-effects meta-analyses were used to estimate pooled summary effects of an LF diet on the depression score (as Hedges g). DATA ANALYSIS: Finding from 10 trials with 50 846 participants indicated no significant change in depression score following LF diets in comparison with usual diet (Hedges g = -0.11; 95% CI, -0.25 to 0.03; P = 0.12; I2 = 70.7% [for I2, 95% CI, 44%, 85%]). However, a significant improvement was observed in both usual diet and LF diets when the content of protein was 15-20% of calorie intake (LF, normal protein diet: n = 5, Hedges g = -0.21, 95% CI, -0.24 to -0.01, P = 0.04, I2 = 0%; usual, normal protein diet: n = 3, Hedges g = -0.28, 95% CI, -0.51 to -0.05, P = 0.01, I2 = 0%). Sensitivity analysis also found the depression score improved following LF diet intervention in participants without baseline depression. CONCLUSION: This study revealed that LF diet may have small beneficial effect on depression score in the studies enrolled mentally healthy participants. Moreover, achieving to adequate dietary protein is likely to be a better intervention than manipulating dietary fat to improve depression scores. However, it is not clear whether this effect will last in the long term. Conducting more studies may change the results due to the low-certainty of evidence. SYSTEMATIC REVIEW REGISTRATION: CRD42023420978 (https://www.crd.york.ac.uk/PROSPERO).

The association of major dietary patterns with odds and severity of anxiety disorders: a case-control study.

Background: In the present study, we explored the association between major dietary patterns, odds, and severity of anxiety disorders, which has not been clarified to date.Methods: This case-control study was conducted on 85 patients who were group-matched by gender with 170 healthy subjects. Dietary intakes were evaluated applying a 147-item validated food frequency questionnaire (FFQ). Anthropometric data collection was accomplished based on precise clinical assessments. Major dietary patterns were identified using principal component analysis (PCA). Multivariate odds ratios (OR) with 95% confidence intervals (CI) were used to investigate the association of the identified dietary patterns with anxiety disorders. Multiple linear regression analysis was used to evaluate the association between the GAD-7 score and major dietary pattern scores.Results: Three major dietary patterns were derived through PCA labeled as 'healthy', 'Western', and 'Mixed'. Those in the top tertile of the healthy dietary pattern were less likely to have anxiety disorders (OR = 0.26; 95%CI: 0.10, 0.66), while no significant relationship was found between Western and mixed dietary patterns and the odds of anxiety disorders. The severity of anxiety disorders, assessed by the GAD-7 score, was reduced by higher adherence to healthy dietary pattern (P = 0.003), and increased by greater adherence to mixed (P = 0.002) and Western (P = 0.001) dietary patterns.Conclusion: We provided evidence demonstrating an inverse association of healthy dietary pattern with odds, and severity of anxiety disorders. Also, higher adherence to Western and mixed dietary patterns resulted in greater GAD-7 scores.

Comparative effects of nutraceuticals on body weight in adults with overweight or obesity: A systematic review and network meta-analysis of 111 randomized clinical trials.

There is no research on the comparative effects of nutraceuticals on weight loss in adults with overweight or obesity. This study aimed at quantifying and ranking the effects of different nutraceuticals on weight loss. We searched PubMed, Scopus, and Web of Science to November 2022. We included randomized trials evaluating the comparative effects of two or more nutraceuticals, or compared a nutraceutical against a placebo for weight loss in adults with overweight or obesity. We conducted random-effects network meta-analysis with a Frequentist framework to estimate mean difference [MD] and 95% confidence interval [CI] of the effect of nutraceuticals on weight loss. One hundred and eleven RCTs with 6171 participants that investigated the effects of 18 nutraceuticals on body weight were eligible. In the main analysis incorporating all trials, there was high certainty of evidence for supplementation of spirulina (MD: -1.77 kg, 95% CI: -2.77, -0.78) and moderate certainty of evidence that supplementation of curcumin (MD: -0.82 kg, 95% CI: -1.33, -0.30), psyllium (MD: -3.70 kg, 95% CI: -5.18, -2.22), chitosan (MD: -1.70 kg, 95% CI: -2.62, -0.78), and Nigella sativa (MD: -2.09 kg, 95%CI: -2.92, -1.26) could result in a small improvement in body weight. Supplementations with green tea (MD: -1.25 kg, 95%CI: -1.68, -0.82) and glucomannan (MD: -1.36 kg, 95%CI: -2.17, -0.54) demonstrated small weight loss, also the certainty of evidence was rated low. Based on our findings, supplementations with nutraceuticals can result in a small weight loss in adults with overweight or obesity.

Association between empirical dietary inflammatory index, odds, and severity of anxiety disorders: A case-control study.

Diet may be a modifiable factor in the prevention of psychiatric disorders by modulating inflammation. In this study, we evaluated the association between empirical dietary inflammatory index (EDII) that is designed to evaluate the inflammatory potential of diets and anxiety disorders (AD) in adults. This case-control study was carried out on 85 patients who were group matched by gender with 170 healthy subjects. Data for dietary intake were assessed by using a 147-item validated food frequency questionnaire (FFQ). Anthropometric measures were collected using standard methods. EDII score was developed according to participants' dietary intakes of 28 predefined food groups. Multivariate odds ratios (OR) with 95% confidence intervals (CI) were used to investigate the association of empirically derived inflammatory potential of the diet and anxiety disorder. We observed that after adjusting for confounders, individuals in the top category of EDII score were 2.09 fold more likely to have anxiety disorder compared with those in the bottom category (OR: 2.09, 95% CI: 1.01, 4.33). Also, higher EDII contributed to a higher GAD-7 score (p < .001). There was a significant positive linear association between EDII and AD (ß = 3.64, p < .001). After controlling for potential confounders AD had a strong positive correlation with the EDII score (r = .61, p-value <.001). In conclusion, in this case-control study, we realized that there is a positive association between the EDII score, odds, and severity of anxiety disorder. Ultimately, the potential role necessitates clarifying this association by conducting large-population prospective cohort studies.

The combined association of dietary inflammatory index and resting metabolic rate on cardiorespiratory fitness in adults.

BACKGROUND: No study has examined the combined association of dietary inflammatory index (DII) of the diet and resting metabolic rate (RMR) on cardiorespiratory fitness (CRF). Therefore, we investigated the combined association between DII and RMR on CRF. METHODS: This cross-sectional study was conducted on 270 adult subjects. The DII was calculated using a validated semi-quantified food frequency questionnaire. RMR was measured using an indirect calorimetric method. Socioeconomic status, anthropometric measures, body composition and blood pressure were documented by a trained interviewer. CRF was assessed by using Bruce protocol. Binary logistic regression was performed to find the association of CRF with DII/RMR categories in various models. RESULTS: The participants categorized into four groups including: (1) low DII/high RMR, (2) low DII/low RMR, (3) high DII/low RMR, (4) high DII/high RMR. The mean of VO2Max (mL/kg/min), VO2max (L/min) and VO2max relative to lean body mass (LBM) was lower in participants that were classified as high DII/low RMR compared to those in low DII/high RMR. After controlling for age, sex, education status, smoking status, and physical activity those who were in the high DII/low RMR group, compared to the low DII/high RMR group were 28% less likely to have higher VO2max (ml/kg/min) (OR 0.72; 95% CI 0.18, 0.82, p = 0.04). Moreover, had 25% lower odds of VO2max (L/min) which was significant (OR 0.75, 95% CI 0.11, 0.89, p = 0.03). In addition, were 21% less likely to have higher VO2max (LBM) (OR 0.79; 95% CI 0.30, 0.92, p = 0.02). CONCLUSIONS: Overall, consumption of a pro-inflammatory diet in combination with low RMR status is associated with lower odds of CRF compared to those who had anti-inflammatory diet in combination with high RMR status among Iranian healthy adults. This study suggests that researchers should focus on combined relationships rather than single pair-wise associations for having a better judgment.

Adherence to the MIND diet is inversely associated with odds and severity of anxiety disorders: a case-control study.

BACKGROUND: The association between the Mediterranean-DASH diet Intervention for Neurodegenerative Delay (MIND) diet, odds, and severity of anxiety disorders (AD) is still unclear. We aimed to investigate whether adherence to MIND diet is associated with odds and severity of AD. METHODS: The present case-control study carried out on 85 patients who were group matched by gender with 170 healthy subjects. Data for dietary intake was assessed by using a 147-item validated food frequency questionnaire (FFQ). Anthropometric measures were collected using standard methods. The MIND diet score was calculated using FFQ. We assessed anxiety disorder severity using the Generalized Anxiety Disorder-7 (GAD-7) questionnaire. Multivariate odds ratios (OR) with 95% confidence intervals (CI) were used to investigate the association of MIND diet and anxiety disorder. RESULTS: We observed that higher adherence to MIND diet was associated with the lower GAD-7 score (p < 0.001). Individuals in the top category of MIND diet score were 97% less likely to have AD compared with those in the bottom category (OR: 0.03, 95% CI: 0.01, 0.09). There was significant reverse linear association between MIND diet score and AD (ß = -3.63, p < 0.001). CONCLUSIONS: In conclusion, we provided some evidence indicating negative association between adherence to MIND diet, odds, and severity of AD. Finally, due to the probable preventive role of diet, it is vital to clarify the association between diet and AD through large-scale prospective cohort studies in the future.

Association between dietary caffeine, coffee, and tea consumption and depressive symptoms in adults: A systematic review and dose-response meta-analysis of observational studies.

Background: Recent studies have reported an association between dietary caffeine intake (coffee and tea) and the presence of depressive symptoms. However, the findings are not conclusive. Purpose: This study aimed to examine the correlation between the consumption of dietary caffeine (coffee and tea) and the presence of depressive symptoms in adults. Methods: PubMed and Scopus databases were searched until December 2021. Two investigators analyzed data from identified studies and rated the quality of the evidence using the GRADE approach. Using the random-effects models, we estimated the relative risks (RRs) and 95% confidence intervals (CIs). We also modeled the dose-response associations through a one-stage, weighted mixed-effects meta-analysis. Results: A total of 29 eligible studies included a total of 422,586 participants. On comparing the highest with the lowest category in cohort studies, we identified an inverse association between the intake of coffee and depressive symptoms (RR: 0.89, 95%CI: 0.82-0.95; I2 = 63.7%, GRADE = low). There was a 4% reduction in the risk of depression associated with an increase in coffee intake of 240 ml/day (RR: 0.96, 95%CI: 0.95, 0.98; I2 = 22.7%). By comparing the highest category with the lowest category in cohort studies, we discovered that caffeine intake was inversely associated with depressive symptoms (RR: 0.86, 95%CI: 0.79, 0.93; I2 = 0.0%, GRADE = moderate). Based on our data analysis, no correlation exists between tea consumption and depressive symptoms. Conclusion: According to our findings, coffee and dietary caffeine may have a protective effect against the development of depression. However, no evidence suggesting a link between tea consumption and reduced depressive symptoms has been found. Therefore, further longitudinal studies are needed to substantiate the causal relationship between coffee, tea, and caffeine and the risk of depression.

Dose-dependent effect of vinegar on blood pressure: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: There are controversial findings regarding the effect of vinegar on blood pressure based on the evidence accumulated so far. METHODS: A systematic search was conducted through PubMed, Scopus, and ISI Web of Science up to April 2022. We estimated the change in blood pressure for each 30 ml/d increments in vinegar consumption in each trial and then, calculated the mean difference (MD) and 95 %CI using a fixed-effects model. A dose-response meta-analysis of differences in means provided us with the estimation of the dose-dependent effect. The certainty of evidence was rated by the GRADE tool. RESULTS: Each 30 ml/d increment in vinegar consumption reduced SBP by - 3.25 mmHg (95 %CI: - 5.54, - 0.96; I2 = 67.5 %, GRADE = low). Levels of SBP decreased linearly and slightly (Pnonlinearity = 0.69, Pdose-response = 0.02) up to vinegar consumption of 30 ml/d (MD30 ml/d: - 3.36, 95 %CI: - 5.77, - 0.94). Each 30 ml/d increment in vinegar consumption reduced DBP by - 3.33 mmHg (95 %CI: - 4.16, - 2.49; I2 = 57.1 %, GRADE = low). Levels of DBP decreased linearly and slightly (Pnonlinearity = 0.47, Pdose-response = 0.004) up to vinegar consumption of 30 ml/d (MD30 ml/d: - 2.61, 95 %CI: - 4.15, - 1.06) CONCLUSIONS: According to the findings, vinegar significantly reduces systolic and diastolic blood pressure and may be considered an adjunct to hypertension treatment. Thus, clinicians could incorporate vinegar consumption as part of their dietary advice for patients.