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Cancer Causes & Control : CCC Mar 2015To investigate the association between fish consumption and n-3 polyunsaturated fatty acids (n-3 PUFA) and the risk of hepatocellular carcinoma (HCC). (Meta-Analysis)
Meta-Analysis Review
PURPOSE
To investigate the association between fish consumption and n-3 polyunsaturated fatty acids (n-3 PUFA) and the risk of hepatocellular carcinoma (HCC).
METHODS
We identified eligible studies in MEDLINE and EMBASE up to July 2014 and the reference lists of original studies and review articles on this topic. Summary relative risks (SRR) with their 95 % confidence intervals (CI) were calculated with a random effects model.
RESULTS
Eleven studies (three cohort studies, seven retrospective case-control studies, and one nested case-control study) met eligibility criteria. Ten articles investigated fish consumption, two articles investigated n-3 PUFA, and two articles investigated alpha-linolenic acid (ALA). The current data suggest that fish consumption was associated with 35 % reduction in HCC risk (highest vs. lowest category SRRs = 0.65, 95 % CI 0.51-0.79; test for heterogeneity p = 0.057, I (2) = 44.1 %). n-3 PUFA was associated with 51 % reduction in HCC risk (highest vs. lowest category SRRs = 0.49, 95 % CI 0.19-0.79). However, no significant inverse association was found in ALA (SRRs = 0.70, 95 % CI 0.30-1.10).
CONCLUSION
Our meta-analysis of observational studies provides evidence that fish consumption and n-3 PUFA has inverse association with the risk of HCC.
Topics: Animals; Anticarcinogenic Agents; Carcinoma, Hepatocellular; Case-Control Studies; Cohort Studies; Diet; Fatty Acids, Omega-3; Female; Fish Products; Fishes; Humans; Liver Neoplasms; Male; Observational Studies as Topic; Retrospective Studies; Risk; alpha-Linolenic Acid
PubMed: 25534918
DOI: 10.1007/s10552-014-0512-1 -
Meat Science Dec 2014Nutritional quality of pork is a significant factor for consumers' health. Feeding n-3 PUFA to pigs, using linseed, improves pork nutritional quality. A meta-analysis... (Meta-Analysis)
Meta-Analysis Review
Nutritional quality of pork is a significant factor for consumers' health. Feeding n-3 PUFA to pigs, using linseed, improves pork nutritional quality. A meta-analysis involving 1006 pigs reported in 24 publications was carried out to assess the effects of dietary linseed on alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) content in muscle and adipose tissue. Data showed positive effects of n-3 PUFA on muscle fatty acid composition: ALA+137%, EPA+188%, DPA+51% and DHA+12%. Same results were observed in adipose tissue: ALA+297%, EPA+149%, DPA+88% and DHA+18%. A positive correlation between dietary treatment and ALA and EPA content in muscle (P<0.001) and adipose tissue (P=0.036) was observed. A significant association between DPA (P=0.04) and DHA (P=0.011) and live weight in muscle was observed. Feeding linseed to pig improves the nutritional pork quality, raising the n-3 PUFA content in muscle and adipose tissue.
Topics: Animal Feed; Animals; Diet; Food Quality; Linseed Oil; Meat; Nutritive Value; Swine
PubMed: 25089794
DOI: 10.1016/j.meatsci.2014.06.041 -
The British Journal of Nutrition Mar 2016Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of... (Meta-Analysis)
Meta-Analysis Review
Higher PUFA and n-3 PUFA, conjugated linoleic acid, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: a systematic literature review and meta- and redundancy analyses.
Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of organic production standards affects milk quality. Here we report results of meta-analyses based on 170 published studies comparing the nutrient content of organic and conventional bovine milk. There were no significant differences in total SFA and MUFA concentrations between organic and conventional milk. However, concentrations of total PUFA and n-3 PUFA were significantly higher in organic milk, by an estimated 7 (95 % CI -1, 15) % and 56 (95 % CI 38, 74) %, respectively. Concentrations of α-linolenic acid (ALA), very long-chain n-3 fatty acids (EPA+DPA+DHA) and conjugated linoleic acid were also significantly higher in organic milk, by an 69 (95 % CI 53, 84) %, 57 (95 % CI 27, 87) % and 41 (95 % CI 14, 68) %, respectively. As there were no significant differences in total n-6 PUFA and linoleic acid (LA) concentrations, the n-6:n-3 and LA:ALA ratios were lower in organic milk, by an estimated 71 (95 % CI -122, -20) % and 93 (95 % CI -116, -70) %. It is concluded that organic bovine milk has a more desirable fatty acid composition than conventional milk. Meta-analyses also showed that organic milk has significantly higher α-tocopherol and Fe, but lower I and Se concentrations. Redundancy analysis of data from a large cross-European milk quality survey indicates that the higher grazing/conserved forage intakes in organic systems were the main reason for milk composition differences.
Topics: Animals; Cattle; Dairying; Dietary Fats, Unsaturated; Evidence-Based Practice; Fatty Acids, Omega-3; Food, Organic; Humans; Iodine; Iron, Dietary; Linoleic Acids, Conjugated; Livestock; Milk; Nutritive Value; Selenium; alpha-Tocopherol
PubMed: 26878105
DOI: 10.1017/S0007114516000349 -
International Journal of Evidence-based... Jun 2016This systematic review sought to identify the association of dietary intake and supplementation of specific polyunsaturated fatty acids with inflammation and function in... (Review)
Review
The association of dietary intake and supplementation of specific polyunsaturated fatty acids with inflammation and functional capacity in chronic obstructive pulmonary disease: a systematic review.
OBJECTIVE
This systematic review sought to identify the association of dietary intake and supplementation of specific polyunsaturated fatty acids with inflammation and function in people with chronic obstructive pulmonary disease (COPD).
DATA SOURCES
We searched electronic databases including PubMed, CINAHL, MEDLINE, EMBASE, The Cochrane Library, ProQuest Dissertations and Theses, Scopus, Google Scholar, Trove, and WHO International Clinical Trials Registry Platform and reference lists of retrieved articles published prior to August 2014.
INCLUSION CRITERIA
We considered observational studies that evaluated dietary intake of omega-3 (eicosapentaenoic acid, docosahexaenoic acid or α-linolenic acid) and/or omega-6 fatty acids (γ-linoleic acid or arachidonic acid), and experimental studies that evaluated omega-3 fatty acid supplementation (containing predominantly one or more omega-3 fatty acids) on airway and systemic inflammatory markers and/or functional capacity outcomes in people with COPD-related diagnoses.
DATA SYNTHESIS
Since statistical pooling was not possible, the findings were presented in narrative form including tables and figures to aid in data presentation when appropriate.
RESULTS
One 8-week randomized controlled trial conducted in 80 COPD patients in the Netherlands showed polyunsaturated fatty acid supplementation significantly improved exercise capacity compared with the control condition [between-group difference in mean peak workload was 9.7 W (2.5-17.0; P = 0.009); and mean duration was 4.3 min (0.6-7.9; P = 0.023)]. One cross-sectional study conducted in 250 COPD patients in Spain found associations of specific dietary omega-3 fatty acids with inflammation were inconsistent.
CONCLUSIONS
Limited evidence provides weak support for the use of omega-3 fatty acid supplementation for reducing chronic inflammation and some support for improving functional capacity in COPD patients. There is no consistent evidence showing that low dietary intake of specific omega-3 fatty acids worsens inflammation and/or function. More evidence is required before routinely incorporating this therapy within COPD management plans.
Topics: Dietary Supplements; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Humans; Inflammation; Pulmonary Disease, Chronic Obstructive; Respiratory Function Tests
PubMed: 26134547
DOI: 10.1097/XEB.0000000000000056 -
The British Journal of Nutrition Apr 2024Maternal diet influences breast milk nutritional profile; however, it is unclear which nutrients and contaminants are particularly responsive to short- and long-term... (Review)
Review
Maternal diet influences breast milk nutritional profile; however, it is unclear which nutrients and contaminants are particularly responsive to short- and long-term changes in maternal intake, and the impact of specific exclusion diets, such as vegan or vegetarian. This study systematically reviewed the literature on the effects of maternal nutrient intake, including exclusion diets, on both the nutrient and contaminant content of breast milk. The electronic databases, PubMed, CENTRAL, Web of Science and CINALH were systematically searched until 4 June 2023, with additionally searches of reference lists (PROSPERO, CRD42020221577). The quality of the studies was examined using Cochrane Risk of Bias tool and Newcastle-Ottawa scale. Eighty-eight studies ( 6577) met the search criteria. Due to high heterogeneity, meta-analysis was not possible. There was strong evidence of response to maternal intakes for DHA and EPA, vitamins A, E and K, iodine and Se in breast milk composition, some evidence of response for -linolenic acid, B vitamins, vitamin C and D, ovalbumin, tyrosine and contaminants, and insufficient evidence to identify the effects arachidonic acid, Cu, Fe, Zn and choline. The paucity of evidence and high heterogeneity among studies reflects the need for more high-quality trials. However, this review identified the importance of maternal intake in the nutritional content of breast milk for a wide range of nutrients and supports the recommendation for supplementation of DHA and vitamin B for those on restrictive diets.
Topics: Humans; Female; Milk, Human; Lactation; Vitamins; Diet; Eating
PubMed: 38053371
DOI: 10.1017/S0007114523002775 -
European Journal of Nutrition Apr 2018The aim of the current meta-analysis was to investigate the effect of increasing dietary ALA intake on the blood concentration of inflammatory markers including tumor... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
The aim of the current meta-analysis was to investigate the effect of increasing dietary ALA intake on the blood concentration of inflammatory markers including tumor necrosis factor (TNF), interleukin 6 (IL-6), C-reactive protein (CRP), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) in adults.
METHODS
After a systemic search on PubMed, Embase, and Cochrane library and bibliographies of relevant articles, 25 randomized controlled trials that met the inclusion criteria were identified.
RESULTS
No significant effect of dietary ALA supplementation was observed on TNF (SMD: -0.03, 95% CI -0.36 to 0.29), IL-6 (SMD: -0.17, 95% CI -0.46 to 0.12), CRP (SMD: -0.06, 95% CI -0.24 to 0.12), sICAM-1 (SMD: -0.06, 95% CI -0.26 to 0.13), and sVCAM-1 (SMD: -0.24, 95% CI -0.56 to 0.09). Subgroup analysis revealed that increasing dietary ALA tends to elevate CRP concentration in healthy subjects. However, the null effect of ALA supplementation on other inflammatory markers was not changed in various subgroups, indicating that the results are stable. Meta-regression results revealed a negative relationship between the effect size on CRP and its baseline concentration. No significant publication bias was observed for all inflammatory markers as suggested by funnel plot and Begg's test.
CONCLUSION
Our meta-analysis did not find any beneficial effect of ALA supplementation on reducing inflammatory markers including TNF, IL-6, CRP, sICAM-1, and sVCAM-1. However, in healthy subjects, ALA supplementation might increase CRP concentration.
Topics: Anti-Inflammatory Agents, Non-Steroidal; Biomarkers; C-Reactive Protein; Chronic Disease; Dietary Supplements; Evidence-Based Medicine; Humans; Inflammation Mediators; Intercellular Adhesion Molecule-1; Interleukin-6; Randomized Controlled Trials as Topic; Solubility; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1; alpha-Linolenic Acid
PubMed: 28275869
DOI: 10.1007/s00394-017-1386-2 -
Nutrition Research (New York, N.Y.) Feb 2023Flaxseed is a functional food because of its high content of alpha-linolenic acid, lignans, and dietary fiber. We hypothesized that flaxseed supplementation would... (Meta-Analysis)
Meta-Analysis Review
Flaxseed is a functional food because of its high content of alpha-linolenic acid, lignans, and dietary fiber. We hypothesized that flaxseed supplementation would improve cardiometabolic parameters in patients with type 2 diabetes mellitus (T2DM); however, clinical trials have shown conflicting results. Therefore, this systematic review and meta-analysis was conducted to determine the impact of flaxseed supplementation in patients with T2DM. Randomized controlled trials were systematically searched in PubMed, Web of Science, Scopus, Cochrane Library, and Embase until 25 March 2022. A total of 13 studies were included, and the results showed that flaxseed supplementation significantly reduced hemoglobin A1c (HbA1c) in participants with T2DM compared with the control group. In contrast, it had no effects on body weight, body mass index, blood pressure, fasting blood glucose (FBG), homeostatic model assessment for insulin resistance, quantitative insulin sensitivity check index, and lipid parameters. In the subgroup analyses, FBG was significantly reduced with supplementation of flaxseed in participants with baseline FBG ≥8.0 mmol/L or baseline HbA1c ≥7.0%. And a significant decrease in HbA1c in participants with baseline HbA1c ≥7.0% after flaxseed supplementation. In addition, subgroup analyses indicated that whole flaxseed supplementation significantly increased high-density lipoprotein cholesterol and reduced total cholesterol or low-density lipoprotein cholesterol in participants with T2DM. In conclusion, flaxseed supplementation significantly reduced HbA1c in participants with T2DM, especially those with poorly controlled blood sugar levels. However, larger scale studies with better designs are needed to confirm insignificant and/or ambiguous findings.
Topics: Humans; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Flax; Dietary Supplements; Cholesterol; Blood Glucose
PubMed: 36640581
DOI: 10.1016/j.nutres.2022.12.008 -
Nutrients Jul 2015Enteral immunomodulatory nutrition is considered as a promising therapy for the treatment of acute lung injury and acute respiratory distress syndrome (ALI/ARDS).... (Meta-Analysis)
Meta-Analysis Review
Enteral Immunomodulatory Diet (Omega-3 Fatty Acid, γ-Linolenic Acid and Antioxidant Supplementation) for Acute Lung Injury and Acute Respiratory Distress Syndrome: An Updated Systematic Review and Meta-Analysis.
UNLABELLED
Enteral immunomodulatory nutrition is considered as a promising therapy for the treatment of acute lung injury and acute respiratory distress syndrome (ALI/ARDS). However, there are still some divergences, and it is unclear whether this treatment should be recommended for patients with ALI/ARDS. Therefore, we conducted this systematic review and meta-analysis to assess the efficacy and safety of an enteral immunomodulatory diet on the clinical outcomes of ALI/ARDS patients.
METHODS
We retrieved potentially relevant clinical trials though electronic databases. All trials of enteral immunomodulatory diet for ALI/ARDS were included. Analyses of the overall all-cause mortality, 28-day ventilator-free days and 28-day intensive care unit (ICU) free days were conducted.
RESULTS
In total six controlled trials were evaluated. The pooled results did not show a significant reduction in the risk of all-cause mortality (M-H RR (the overall Mantel-Haenszel relative risk), 0.81 (95% CI, 0.50-1.31); p = 0.38; 6 trials, n = 717) in ALI/ARDS patients treated with the immunomodulatory diet. This treatment also did not extend the ventilator-free days and ICU-free days. However, patients with high mortality might benefit from this treatment.
CONCLUSIONS
The enteral immunomodulatory diet could not reduce the severity of the patients with ALI/ARDS. Whereas, for ALI/ARDS patients with high mortality, this treatment might reduce the all-cause mortality, but its use should be treated with discretion.
Topics: Acute Lung Injury; Antioxidants; Dietary Fats; Enteral Nutrition; Humans; Respiratory Distress Syndrome; gamma-Linolenic Acid
PubMed: 26184293
DOI: 10.3390/nu7075239 -
Nutrition & Metabolism Oct 2021Flaxseed is widely used as a functional food for its rich sources of linolenic acid, lignans and dietary fibers in the world. This systematic review and dose-response... (Review)
Review
Comparisons of the effects of different flaxseed products consumption on lipid profiles, inflammatory cytokines and anthropometric indices in patients with dyslipidemia related diseases: systematic review and a dose-response meta-analysis of randomized controlled trials.
BACKGROUND
Flaxseed is widely used as a functional food for its rich sources of linolenic acid, lignans and dietary fibers in the world. This systematic review and dose-response meta-analysis on randomized controlled trials (RCTs) is first to evaluate effects of different flaxseed products (whole flaxseed, oil and lignans) on lipid profiles, inflammatory and anthropometric parameters in patients with dyslipidemia related diseases.
METHODS
Literature search was performed in PubMed, Embase, Cochrane Central, Scopus, and Web of Science from the inception dates to January, 2020. Weighted mean differences with the 95% confidence interval (CI) were pooled using fix or random-effects models.
RESULTS
Thirty-one RCTs involving 1,698 participants were included. The present meta-analysis revealed that flaxseed consumption had an overall beneficial effect on serum TC, LDL-C, TG, apo B and IL-6 in patients with dyslipidemia related diseases, but not on apo A, HDL-C, hs-CRP, CRP and anthropometric indices. However, different flaxseed products showed obviously different effects. Whole flaxseed supplementation significantly reduced TC (- 11.85 mg/dl, 95% CI - 20.12 to - 3.57, P = 0.005), LDL-C (- 10.51 mg/dl, 95% CI - 14.96 to - 6.06, P < 0.001), TG (- 19.77 mg/dl, 95% CI - 33.61 to - 5.94, P = 0.005), apolipoprotein B (- 5.73 mg/dl, 95% CI - 7.53 to - 3.93, P < 0.001), TC/HDL-C (- 0.10, 95% CI - 0.19 to - 0.003, P = 0.044) and weight (- 0.40 kg, 95% CI - 0.76 to - 0.05, P = 0.027); Lignans supplementation significantly reduced TC (- 17.86 mg/dl, P = 0.004), LDL-C (- 15.47 mg/dl, P < 0.001) and TC/HDL-C (- 0.45, P = 0.04). Although flaxseed oil supplementation had no such lowering-effect on lipid, meta-analysis revealed its lowering-effect on IL-6 (- 0.35 pg/ml, P = 0.033) and hs-CRP (- 1.54 mg/l, P = 0.004). Subgroup analysis revealed that whole flaxseed decreased TC, LDL-C and TG levels irrespective of country and the intervention time prescribed, but was more pronounced when the dose of whole flaxseed was ≤ 30 g/day (TC: WMD - 13.61 mg/mL; LDL-C: WMD - 10.52 mg/mL; TG: WMD - 23.52 mg/mL), rather not a dose > 30 g/day. Moreover, a linear relationship between dose of whole flaxseed and absolute changes in C-reactive protein (P = 0.036) and a nonlinear relationship between with IL-6 (P < 0.001) were detected.
CONCLUSIONS
Flaxseed intervention suggested the positive effects on lipid profiles, inflammatory cytokines and anthropometric indices in patients with dyslipidemia related diseases. Of these, whole flaxseed and lignans play an important role in reducing blood lipid, while flaxseed oil mainly plays in anti-inflammatory. Lipid- and weight-lowering was significant when whole flaxseed was consumed at doses < 30 mg/d, for lipid status with mixed dyslipidemia and patients with BMI > 25.
PubMed: 34635132
DOI: 10.1186/s12986-021-00619-3 -
The British Journal of Psychiatry : the... Mar 2021There is strong public belief that polyunsaturated fats protect against and ameliorate depression and anxiety. (Meta-Analysis)
Meta-Analysis
BACKGROUND
There is strong public belief that polyunsaturated fats protect against and ameliorate depression and anxiety.
AIMS
To assess effects of increasing omega-3, omega-6 or total polyunsaturated fat on prevention and treatment of depression and anxiety symptoms.
METHOD
We searched widely (Central, Medline and EMBASE to April 2017, trial registers to September 2016, ongoing trials updated to August 2019), including trials of adults with or without depression or anxiety, randomised to increased omega-3, omega-6 or total polyunsaturated fat for ≥24 weeks, excluding multifactorial interventions. Inclusion, data extraction and risk of bias were assessed independently in duplicate, and authors contacted for further data. We used random-effects meta-analysis, sensitivity analyses, subgrouping and Grading of Recommendations, Assessment, Development and Evaluations (GRADE) assessment.
RESULTS
We included 31 trials assessing effects of long-chain omega-3 (n = 41 470), one of alpha-linolenic acid (n = 4837), one of total polyunsaturated fat (n = 4997) and none of omega-6. Meta-analysis suggested that increasing long-chain omega-3 probably has little or no effect on risk of depression symptoms (risk ratio 1.01, 95% CI 0.92-1.10, I2 = 0%, median dose 0.95 g/d, duration 12 months) or anxiety symptoms (standardised mean difference 0.15, 95% CI 0.05-0.26, I2 = 0%, median dose 1.1 g/d, duration 6 months; both moderate-quality evidence). Evidence of effects on depression severity and remission in existing depression were unclear (very-low-quality evidence). Results did not differ by risk of bias, omega-3 dose, duration or nutrients replaced. Increasing alpha-linolenic acid by 2 g/d may increase risk of depression symptoms very slightly over 40 months (number needed to harm, 1000).
CONCLUSIONS
Long-chain omega-3 supplementation probably has little or no effect in preventing depression or anxiety symptoms.
DECLARATION OF INTEREST
L.H. and A.A. were funded to attend the World Health Organization Nutrition Guidance Expert Advisory Group (NUGAG) Subgroup on Diet and Health meetings and present review results. The authors report no other conflicts of interest.
Topics: Adult; Anxiety; Cardiovascular Diseases; Cause of Death; Depression; Humans; Primary Prevention; Randomized Controlled Trials as Topic; Secondary Prevention
PubMed: 31647041
DOI: 10.1192/bjp.2019.234