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Dietary Cholesterol and Cardiovascular Risk: A Science Advisory From the American Heart Association.Circulation Jan 2020The elimination of specific dietary cholesterol target recommendations in recent guidelines has raised questions about its role with respect to cardiovascular disease.... (Meta-Analysis)
Meta-Analysis
The elimination of specific dietary cholesterol target recommendations in recent guidelines has raised questions about its role with respect to cardiovascular disease. This advisory was developed after a review of human studies on the relationship of dietary cholesterol with blood lipids, lipoproteins, and cardiovascular disease risk to address questions about the relevance of dietary cholesterol guidance for heart health. Evidence from observational studies conducted in several countries generally does not indicate a significant association with cardiovascular disease risk. Although meta-analyses of intervention studies differ in their findings, most associate intakes of cholesterol that exceed current average levels with elevated total or low-density lipoprotein cholesterol concentrations. Dietary guidance should focus on healthy dietary patterns (eg, Mediterranean-style and DASH [Dietary Approaches to Stop Hypertension]-style diets) that are inherently relatively low in cholesterol with typical levels similar to the current US intake. These patterns emphasize fruits, vegetables, whole grains, low-fat or fat-free dairy products, lean protein sources, nuts, seeds, and liquid vegetable oils. A recommendation that gives a specific dietary cholesterol target within the context of food-based advice is challenging for clinicians and consumers to implement; hence, guidance focused on dietary patterns is more likely to improve diet quality and to promote cardiovascular health.
Topics: Cardiovascular Diseases; Cholesterol, Dietary; Diet, Western; Humans; Nutrition Policy; Recommended Dietary Allowances
PubMed: 31838890
DOI: 10.1161/CIR.0000000000000743 -
Circulation May 2022Despite substantial research highlighting the importance of exogenous dietary cholesterol intake and endogenous serum cholesterol level in human health, a thorough... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Despite substantial research highlighting the importance of exogenous dietary cholesterol intake and endogenous serum cholesterol level in human health, a thorough evaluation of the associations is lacking. Our study objective was to examine overall and cause-specific mortality in relation to dietary and serum cholesterol, as well as egg consumption, and conduct an updated meta-regression analysis of cohort studies.
METHODS
We conducted a prospective analysis of 27 078 men in the ATBC Study (Alpha-Tocopherol, Beta-Carotene Cancer Prevention). Multivariable-controlled cause-specific Cox proportional hazards regression models were used to calculate hazard ratios and 31-year absolute mortality risk differences. A systematic review and meta-analysis of cohort studies was also performed (PROSPERO [URL: https://www.crd.york.ac.uk/prospero/; Unique identifier: CRD42021272756]).
RESULTS
Based on 482 316 person-years of follow-up, we identified 22 035 deaths, including 9110 deaths from cardiovascular disease (CVD). Greater dietary cholesterol and egg consumption were associated with increased risk of overall and CVD-related mortality. Hazard ratios for each additional 300 mg cholesterol intake per day were 1.10 and 1.13 for overall and CVD-related mortality, respectively; for each additional 50-g egg consumed daily, hazard ratios were 1.06 and 1.09, respectively, for overall and CVD-related mortality (all values<0.0001). After multivariable adjustment, higher serum total cholesterol concentrations were associated with increased risk of CVD-related mortality (hazard ratios per 1 SD increment, 1.14; <0.0001). The observed associations were generally similar across cohort subgroups. The updated meta-analysis of cohort studies on the basis of 49 risk estimates, 3 601 401 participants, and 255 479 events showed consumption of 1 additional 50-g egg daily was associated with significantly increased CVD risk (pooled relative risk, 1.04 [95% CI, 1.00-1.08]; I=80.1%). In the subgroup analysis of geographic regions (=0.02), an increase of 50-g egg consumed daily was associated with a higher risk of CVD in US cohorts (pooled relative risk, 1.08 [95% CI, 1.02-1.14]) and appeared related to a higher CVD risk in European cohorts with borderline significance (pooled relative risk, 1.05), but was not associated with CVD risk in Asian cohorts.
CONCLUSIONS
In this prospective cohort study and updated meta-analysis, greater dietary cholesterol and egg consumption were associated with increased risk of overall and CVD-related mortality. Our findings support restricted consumption of dietary cholesterol as a means to improve long-term health and longevity.
Topics: Cardiovascular Diseases; Cause of Death; Cholesterol, Dietary; Eggs; Humans; Male; Prospective Studies; Risk Factors
PubMed: 35360933
DOI: 10.1161/CIRCULATIONAHA.121.057642 -
Nutrients Jul 2023Psoriasis is a chronic immune-dysregulated inflammatory disease and hypovitaminosis D is considered a risk factor. We conducted an online database search to review and... (Meta-Analysis)
Meta-Analysis Review
Psoriasis is a chronic immune-dysregulated inflammatory disease and hypovitaminosis D is considered a risk factor. We conducted an online database search to review and meta-analyze the relationship between vitamin D, other bone metabolism parameters, and psoriasis. The efficacy of oral vitamin D supplementation in improving Psoriasis Area and Severity Index (PASI) was also evaluated. Non-original articles, case reports, and animal studies were excluded. Bias risk was assessed according to the Cochrane Collaboration's tool and the Newcastle-Ottawa scale in randomized controlled trials (RCTs) and case-control studies, respectively. Unstandardized mean differences were used for data synthesis. Twenty-three studies reported serum 25 hydroxyvitamin D (25(OH)D) levels in 1876 psoriasis patients and 7532 controls. Psoriasis patients had significantly lower 25(OH)D levels than controls (21.0 ± 8.3 vs. 27.3 ± 9.8, < 0.00001). Conversely, 450 psoriasis patients had lower levels of parathormone than 417 controls (38.7 ± 12.8 vs. 43.7 ± 16.5, = 0.015). Four RCTs examined the effect of oral vitamin D supplementation on psoriasis for 173 patients and 160 patients were treated with placebo. No significant differences were found in PASI after 3, 6, and 12 months of supplementation. It is shown that 25(OH)D serum levels are significantly lower in psoriasis, but, although the granularity of RCT methodology may have influenced the pooled analysis, vitamin D supplementation did not seem to improve clinical manifestations.
Topics: Humans; Vitamin D; Vitamins; Psoriasis; Vitamin D Deficiency; Calcifediol; Dietary Supplements
PubMed: 37571324
DOI: 10.3390/nu15153387 -
Critical Reviews in Food Science and... 2019This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of ginger intake on weight loss, glycemic control... (Meta-Analysis)
Meta-Analysis
The effects of ginger intake on weight loss and metabolic profiles among overweight and obese subjects: A systematic review and meta-analysis of randomized controlled trials.
This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of ginger intake on weight loss, glycemic control and lipid profiles among overweight and obese subjects. We searched the following databases through November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. Data were pooled using the inverse variance method and expressed as Standardized Mean Difference (SMD) with 95% Confidence Intervals (95% CI). Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I). Overall, 14 studies were included in the meta-analyses. Fourteen RCTs with 473 subjects were included in our meta-analysis. The results indicated that the supplementation with ginger significantly decreased body weight (BW) (SMD -0.66; 95% CI, -1.31, -0.01; P = 0.04), waist-to-hip ratio (WHR) (SMD -0.49; 95% CI, -0.82, -0.17; P = 0.003), hip ratio (HR) (SMD -0.42; 95% CI, -0.77, -0.08; P = 0.01), fasting glucose (SMD -0.68; 95% CI, -1.23, -0.05; P = 0.03) and insulin resistance index (HOMA-IR) (SMD -1.67; 95% CI, -2.86, -0.48; P = 0.006), and significantly increased HDL-cholesterol levels (SMD 0.40; 95% CI, 0.10, 0.70; P = 0.009). We found no detrimental effect of ginger on body mass index (BMI) (SMD -0.65; 95% CI, -1.36, 0.06; P = 0.074), insulin (SMD -0.54; 95% CI, -1.43, 0.35; P = 0.23), triglycerides (SMD -0.27; 95% CI, -0.71, 0.18; P = 0.24), total- (SMD -0.20; 95% CI, -0.58, 0.18; P = 0.30) and LDL-cholesterol (SMD -0.13; 95% CI, -0.51, 0.24; P = 0.48). Overall, the current meta-analysis demonstrated that ginger intake reduced BW, WHR, HR, fasting glucose and HOMA-IR, and increased HDL-cholesterol, but did not affect insulin, BMI, triglycerides, total- and LDL-cholesterol levels.
Topics: Blood Glucose; Body Weight; Cholesterol, HDL; Cholesterol, LDL; Databases, Factual; Dietary Supplements; Fasting; Zingiber officinale; Glucose; Homeostasis; Humans; Insulin; Insulin Resistance; Lipids; Metabolome; Obesity; Overweight; Randomized Controlled Trials as Topic; Triglycerides; Weight Loss
PubMed: 29393665
DOI: 10.1080/10408398.2018.1427044 -
Critical Reviews in Food Science and... 2019Over 60 percent of the human population has a reduced ability to digest lactose due to low levels of lactase enzyme activity. Probiotics are live bacteria or yeast that...
Over 60 percent of the human population has a reduced ability to digest lactose due to low levels of lactase enzyme activity. Probiotics are live bacteria or yeast that supplements the gastrointestinal flora. Studies have shown that probiotics exhibit various health beneficial properties such as improvement of intestinal health, enhancement of the immune responses, and reduction of serum cholesterol. Accumulating evidence has shown that probiotic bacteria in fermented and unfermented milk products can be used to alleviate the clinical symptoms of lactose intolerance (LI). In this systematic review, the effectiveness of probiotics in the treatment of LI was evaluated using 15 randomized double-blind studies. Eight probiotic strains with the greatest number of proven benefits were studied. Results showed varying degrees of efficacy but an overall positive relationship between probiotics and lactose intolerance.
Topics: Animals; Bacteria; Cholesterol; Databases, Factual; Dietary Supplements; Digestion; Double-Blind Method; Fatty Acids, Volatile; Fermentation; Gastrointestinal Microbiome; Humans; Lactose; Lactose Intolerance; Milk; Probiotics; Randomized Controlled Trials as Topic; Yeasts
PubMed: 29425071
DOI: 10.1080/10408398.2018.1425977 -
Nutrition & Diabetes Nov 2020At present, the beneficial effect of the ketogenic diet (KD) on weight loss in obese patients is generally recognized. However, a systematic research on the role of KD... (Meta-Analysis)
Meta-Analysis
BACKGROUND
At present, the beneficial effect of the ketogenic diet (KD) on weight loss in obese patients is generally recognized. However, a systematic research on the role of KD in the improvement of glycemic and lipid metabolism of patients with diabetes is still found scarce.
METHODS
This meta-study employed the meta-analysis model of random effects or of fixed effects to analyze the average difference before and after KD and the corresponding 95% CI, thereby evaluating the effect of KD on T2DM.
RESULTS
After KD intervention, in terms of glycemic control, the level of fasting blood glucose decreased by 1.29 mmol/L (95% CI: -1.78 to -0.79) on average, and glycated hemoglobin A1c by 1.07 (95% CI: -1.37 to -0.78). As for lipid metabolism, triglyceride was decreased by 0.72 (95% CI: -1.01 to -0.43) on average, total cholesterol by 0.33 (95% CI: -0.66 to -0.01), and low-density lipoprotein by 0.05 (95% CI: -0.25 to -0.15); yet, high-density lipoprotein increased by 0.14 (95% CI: 0.03-0.25). In addition, patients' weight decreased by 8.66 (95% CI: -11.40 to -5.92), waist circumference by 9.17 (95% CI: -10.67 to -7.66), and BMI by 3.13 (95% CI: -3.31 to -2.95).
CONCLUSION
KD not only has a therapeutic effect on glycemic and lipid control among patients with T2DM but also significantly contributes to their weight loss.
Topics: Adult; Aged; Blood Glucose; Body Mass Index; Cholesterol; Diabetes Mellitus, Type 2; Diet, Ketogenic; Female; Glycated Hemoglobin; Glycemic Control; Humans; Insulin Resistance; Lipid Metabolism; Lipids; Male; Middle Aged; Triglycerides; Waist Circumference; Weight Loss
PubMed: 33257645
DOI: 10.1038/s41387-020-00142-z -
The Cochrane Database of Systematic... May 2020Reducing saturated fat reduces serum cholesterol, but effects on other intermediate outcomes may be less clear. Additionally, it is unclear whether the energy from... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Reducing saturated fat reduces serum cholesterol, but effects on other intermediate outcomes may be less clear. Additionally, it is unclear whether the energy from saturated fats eliminated from the diet are more helpfully replaced by polyunsaturated fats, monounsaturated fats, carbohydrate or protein.
OBJECTIVES
To assess the effect of reducing saturated fat intake and replacing it with carbohydrate (CHO), polyunsaturated (PUFA), monounsaturated fat (MUFA) and/or protein on mortality and cardiovascular morbidity, using all available randomised clinical trials.
SEARCH METHODS
We updated our searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid) and Embase (Ovid) on 15 October 2019, and searched Clinicaltrials.gov and WHO International Clinical Trials Registry Platform (ICTRP) on 17 October 2019.
SELECTION CRITERIA
Included trials fulfilled the following criteria: 1) randomised; 2) intention to reduce saturated fat intake OR intention to alter dietary fats and achieving a reduction in saturated fat; 3) compared with higher saturated fat intake or usual diet; 4) not multifactorial; 5) in adult humans with or without cardiovascular disease (but not acutely ill, pregnant or breastfeeding); 6) intervention duration at least 24 months; 7) mortality or cardiovascular morbidity data available.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed inclusion, extracted study data and assessed risk of bias. We performed random-effects meta-analyses, meta-regression, subgrouping, sensitivity analyses, funnel plots and GRADE assessment.
MAIN RESULTS
We included 15 randomised controlled trials (RCTs) (16 comparisons, ~59,000 participants), that used a variety of interventions from providing all food to advice on reducing saturated fat. The included long-term trials suggested that reducing dietary saturated fat reduced the risk of combined cardiovascular events by 21% (risk ratio (RR) 0.79; 95% confidence interval (CI) 0.66 to 0.93, 11 trials, 53,300 participants of whom 8% had a cardiovascular event, I² = 65%, GRADE moderate-quality evidence). Meta-regression suggested that greater reductions in saturated fat (reflected in greater reductions in serum cholesterol) resulted in greater reductions in risk of CVD events, explaining most heterogeneity between trials. The number needed to treat for an additional beneficial outcome (NNTB) was 56 in primary prevention trials, so 56 people need to reduce their saturated fat intake for ~four years for one person to avoid experiencing a CVD event. In secondary prevention trials, the NNTB was 32. Subgrouping did not suggest significant differences between replacement of saturated fat calories with polyunsaturated fat or carbohydrate, and data on replacement with monounsaturated fat and protein was very limited. We found little or no effect of reducing saturated fat on all-cause mortality (RR 0.96; 95% CI 0.90 to 1.03; 11 trials, 55,858 participants) or cardiovascular mortality (RR 0.95; 95% CI 0.80 to 1.12, 10 trials, 53,421 participants), both with GRADE moderate-quality evidence. There was little or no effect of reducing saturated fats on non-fatal myocardial infarction (RR 0.97, 95% CI 0.87 to 1.07) or CHD mortality (RR 0.97, 95% CI 0.82 to 1.16, both low-quality evidence), but effects on total (fatal or non-fatal) myocardial infarction, stroke and CHD events (fatal or non-fatal) were all unclear as the evidence was of very low quality. There was little or no effect on cancer mortality, cancer diagnoses, diabetes diagnosis, HDL cholesterol, serum triglycerides or blood pressure, and small reductions in weight, serum total cholesterol, LDL cholesterol and BMI. There was no evidence of harmful effects of reducing saturated fat intakes.
AUTHORS' CONCLUSIONS
The findings of this updated review suggest that reducing saturated fat intake for at least two years causes a potentially important reduction in combined cardiovascular events. Replacing the energy from saturated fat with polyunsaturated fat or carbohydrate appear to be useful strategies, while effects of replacement with monounsaturated fat are unclear. The reduction in combined cardiovascular events resulting from reducing saturated fat did not alter by study duration, sex or baseline level of cardiovascular risk, but greater reduction in saturated fat caused greater reductions in cardiovascular events.
Topics: Adult; Cardiovascular Diseases; Cause of Death; Cholesterol; Dietary Carbohydrates; Dietary Fats; Dietary Fats, Unsaturated; Dietary Proteins; Energy Intake; Fatty Acids; Female; Humans; Male; Myocardial Infarction; Randomized Controlled Trials as Topic; Stroke
PubMed: 32428300
DOI: 10.1002/14651858.CD011737.pub2 -
BMJ Open Aug 2015To summarise the evidence about the efficacy of a Mediterranean diet on the management of type 2 diabetes and prediabetic states. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To summarise the evidence about the efficacy of a Mediterranean diet on the management of type 2 diabetes and prediabetic states.
DESIGN
A systematic review of all meta-analyses and randomised controlled trials (RCTs) that compared the Mediterranean diet with a control diet on the treatment of type 2 diabetes and prediabetic states was conducted. Electronic searches were carried out up to January 2015. Trials were included for meta-analyses if they had a control group treated with another diet, if they were of sufficient duration (at least 6 months), and if they had at least 30 participants in each arm. A random-effect model was used to pool data.
PARTICIPANTS
Adults with or at risk for type 2 diabetes.
INTERVENTIONS
Dietary patterns that described themselves as using a 'Mediterranean' dietary pattern.
OUTCOME MEASURES
The outcomes were glycaemic control, cardiovascular risk factors and remission from the metabolic syndrome.
RESULTS
From 2824 studies, 8 meta-analyses and 5 RCTs were eligible. A 'de novo' meta-analysis of 3 long-term (>6 months) RCTs of the Mediterranean diet and glycaemic control of diabetes favoured the Mediterranean diet as compared with lower fat diets. Another 'de novo' meta-analysis of two long-term RCTs showed a 49% increased probability of remission from the metabolic syndrome. 5 meta-analyses showed a favourable effect of the Mediterranean diet, as compared with other diets, on body weight, total cholesterol and high-density lipoprotein cholesterol. 2 meta-analyses demonstrated that higher adherence to the Mediterranean diet reduced the risk of future diabetes by 19-23%.
CONCLUSIONS
The Mediterranean diet was associated with better glycaemic control and cardiovascular risk factors than control diets, including a lower fat diet, suggesting that it is suitable for the overall management of type 2 diabetes.
Topics: Adult; Blood Glucose; Cardiovascular Diseases; Cholesterol, HDL; Diabetes Mellitus, Type 2; Diet, Fat-Restricted; Diet, Mediterranean; Humans; Randomized Controlled Trials as Topic; Risk Factors; Weight Loss
PubMed: 26260349
DOI: 10.1136/bmjopen-2015-008222 -
Nutrition (Burbank, Los Angeles County,... Sep 2020To the best of our knowledge, no systematic review and meta-analysis has evaluated the cholesterol-lowering effects of intermittent fasting (IF) and energy-restricted... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To the best of our knowledge, no systematic review and meta-analysis has evaluated the cholesterol-lowering effects of intermittent fasting (IF) and energy-restricted diets (ERD) compared with control groups. The aim of this review and meta-analysis was to summarize the effects of controlled clinical trials examining the influence of IF and ERD on lipid profiles.
METHODS
A systematic review of four independent databases (PubMed/Medline, Scopus, Web of Science and Google Scholar) was performed to identify clinical trials reporting the effects of IF or ERD, relative to non-diet controls, on lipid profiles in humans. A random-effects model, employing the method of DerSimonian and Laird, was used to evaluate effect sizes, and results were expressed as weighted mean difference (WMD) and 95% confidence intervals (CIs). Heterogeneity between studies was calculated using Higgins I, with values ≥50% considered to represent high heterogeneity. Subgroup analyses were performed to examine the influence of intervention type, baseline lipid concentrations, degree of energy deficit, sex, health status, and intervention duration.
RESULTS
For the outcomes of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triacylglycerols (TG), there were 34, 33, 35, and 33 studies meeting all inclusion criteria, respectively. Overall, results from the random-effects model indicated that IF and ERD interventions resulted significant changes in TC (WMD, -6.93 mg/dL; 95% CI, -10.18 to -3.67; P < 0.001; I = 78.2%), LDL-C (WMD, -6.16 mg/dL; 95% CI, -8.42 to -3.90; P ˂ 0.001; I = 52%), and TG concentrations (WMD, -6.46 mg/dL; 95% CI, -10.64 to -2.27; P = 0.002; I = 61%). HDL-C concentrations did not change significantly after IF or ERD (WMD, 0.50 mg/dL; 95% CI, -0.69 to 1.70; P = 0.411; I = 80%). Subgroup analyses indicated potentially differential effects between subgroups for one or more lipid parameters in the majority of analyses.
CONCLUSIONS
Relative to a non-diet control, IF and ERD are effective for the improvement of circulating TC, LDL-C, and TG concentrations, but have no meaningful effects on HDL-C concentration. These effects are influenced by several factors that may inform clinical practice and future research. The present results suggest that these dietary practices are a means of enhancing the lipid profile in humans.
Topics: Cholesterol, HDL; Cholesterol, LDL; Fasting; Humans; Lipids; Triglycerides
PubMed: 32428841
DOI: 10.1016/j.nut.2020.110801 -
Journal of Strength and Conditioning... Feb 2017Chiang, C-m, Ismaeel, A, Griffis, RB, and Weems, S. Effects of vitamin D supplementation on muscle strength in athletes: A systematic review. J Strength Cond Res 31(2):... (Review)
Review
Chiang, C-m, Ismaeel, A, Griffis, RB, and Weems, S. Effects of vitamin D supplementation on muscle strength in athletes: A systematic review. J Strength Cond Res 31(2): 566-574, 2017-The purpose of this systematic review of the literature was to investigate the effects of vitamin D supplementation on muscle strength in athletes. A computerized literature search of 3 databases (PubMed, MEDLINE, and Scopus) was performed. Included in the review were randomized controlled trials (RCTs), published in English, which measured serum vitamin D concentrations and muscle strength in healthy, athletic participants aged 18-45 years. Quality was assessed using the PEDro scale. Five RCTs and 1 controlled trial were identified, and quality assessment showed 5 trials were of "excellent quality" and 1 was of "good quality." Trials lasted from 4 weeks to 6 months and dosages ranged from 600 to 5,000 International Units (IU) per day. Vitamin D2 was found to be ineffective at impacting muscle strength in both studies wherein it was administered. In contrast, vitamin D3 was shown to have a positive impact on muscle strength. In 2 studies, strength outcome measures were significantly improved after supplementation (p ≤ 0.05). In the other 2 studies administering vitamin D3, there were trends for improved muscle strength. Specifically, improvements in strength ranged from 1.37 to 18.75%. Additional studies are needed to confirm these associations.
Topics: Adolescent; Adult; Athletes; Cholecalciferol; Controlled Clinical Trials as Topic; Dietary Supplements; Dose-Response Relationship, Drug; Ergocalciferols; Female; Humans; Male; Middle Aged; Muscle Strength; Outcome Assessment, Health Care; Vitamin D; Young Adult
PubMed: 27379960
DOI: 10.1519/JSC.0000000000001518