To update the clinical practice guidelines for nutrition therapy of the European Association for the Study of Diabetes, we conducted a systematic review and meta-analysis of prospective cohort ...studies and randomized clinical trials (RCTs) to evaluate the effect of the Mediterranean diet (MedDiet) on the prevention of cardiovascular disease (CVD) incidence and mortality. We searched Medline, EMBASE (through April 20, 2018) and Cochrane (through May 7, 2018) databases. Pooled relative risks (RRs) and 95% confidence interval (CI) were calculated by the generic inverse variance method. A total of 41 reports (3 RCTs and 38 cohorts) were included. Meta-analyses of RCTs revealed a beneficial effect of the MedDiet on total CVD incidence (RR: 0.62; 95% CI: 0.50, 0.78) and total myocardial infarction (MI) incidence (RR: 0.65; 95% CI: 0.49, 0.88). Meta-analyses of prospective cohort studies, which compared the highest versus lowest categories of MedDiet adherence, revealed an inverse association with total CVD mortality (RR: 0.79; 95% CI: 0.77, 0.82), coronary heart disease (CHD) incidence (RR: 0.73; 95% CI: 0.62, 0.86), CHD mortality (RR: 0.83; 95% CI: 0.75, 0.92), stroke incidence (RR: 0.80; 95% CI: 0.71, 0.90), stroke mortality (RR: 0.87; 95% CI: 0.80, 0.96) and MI incidence (RR: 0.73; 95% CI: 0.61, 0.88). The present study suggests that MedDiet has a beneficial role on CVD prevention in populations inclusive of individuals with diabetes.
Tree nut consumption has been associated with reduced diabetes risk, however, results from randomized trials on glycemic control have been inconsistent.
To provide better evidence for diabetes ...guidelines development, we conducted a systematic review and meta-analysis of randomized controlled trials to assess the effects of tree nuts on markers of glycemic control in individuals with diabetes.
MEDLINE, EMBASE, CINAHL, and Cochrane databases through 6 April 2014.
Randomized controlled trials ≥3 weeks conducted in individuals with diabetes that compare the effect of diets emphasizing tree nuts to isocaloric diets without tree nuts on HbA1c, fasting glucose, fasting insulin, and HOMA-IR.
Two independent reviewer's extracted relevant data and assessed study quality and risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences (MD) with 95% CI's. Heterogeneity was assessed (Cochran Q-statistic) and quantified (I2).
Twelve trials (n = 450) were included. Diets emphasizing tree nuts at a median dose of 56 g/d significantly lowered HbA1c (MD = -0.07% 95% CI:-0.10, -0.03%; P = 0.0003) and fasting glucose (MD = -0.15 mmol/L 95% CI: -0.27, -0.02 mmol/L; P = 0.03) compared with control diets. No significant treatment effects were observed for fasting insulin and HOMA-IR, however the direction of effect favoured tree nuts.
Majority of trials were of short duration and poor quality.
Pooled analyses show that tree nuts improve glycemic control in individuals with type 2 diabetes, supporting their inclusion in a healthy diet. Owing to the uncertainties in our analyses there is a need for longer, higher quality trials with a focus on using nuts to displace high-glycemic index carbohydrates.
ClinicalTrials.gov NCT01630980.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Colonic Health: Fermentation and Short Chain Fatty Acids Wong, Julia M. W; de Souza, Russell; Kendall, Cyril W. C ...
Journal of clinical gastroenterology,
2006-March, Letnik:
40, Številka:
3
Journal Article, Conference Proceeding
Recenzirano
Interest has been recently rekindled in short chain fatty acids (SCFAs) with the emergence of prebiotics and probiotics aimed at improving colonic and systemic health. Dietary carbohydrates, ...specifically resistant starches and dietary fiber, are substrates for fermentation that produce SCFAs, primarily acetate, propionate, and butyrate, as end products. The rate and amount of SCFA production depends on the species and amounts of microflora present in the colon, the substrate source and gut transit time. SCFAs are readily absorbed. Butyrate is the major energy source for colonocytes. Propionate is largely taken up by the liver. Acetate enters the peripheral circulation to be metabolized by peripheral tissues. Specific SCFA may reduce the risk of developing gastrointestinal disorders, cancer, and cardiovascular disease. Acetate is the principal SCFA in the colon, and after absorption it has been shown to increase cholesterol synthesis. However, propionate, a gluconeogenerator, has been shown to inhibit cholesterol synthesis. Therefore, substrates that can decrease the acetatepropionate ratio may reduce serum lipids and possibly cardiovascular disease risk. Butyrate has been studied for its role in nourishing the colonic mucosa and in the prevention of cancer of the colon, by promoting cell differentiation, cell-cycle arrest and apoptosis of transformed colonocytes; inhibiting the enzyme histone deacetylase and decreasing the transformation of primary to secondary bile acids as a result of colonic acidification. Therefore, a greater increase in SCFA production and potentially a greater delivery of SCFA, specifically butyrate, to the distal colon may result in a protective effect. Butyrate irrigation (enema) has also been suggested in the treatment of colitis. More human studies are now needed, especially, given the diverse nature of carbohydrate substrates and the SCFA patterns resulting from their fermentation. Short-term and long-term human studies are particularly required on SCFAs in relation to markers of cancer risk. These studies will be key to the success of dietary recommendations to maximize colonic disease prevention.
Antioxidants have been promoted for cardiovascular disease (CVD) risk reduction and for the prevention of cancer. Our preliminary analysis suggested that only when selenium was present were ...antioxidant mixtures associated with reduced all-cause mortality.
We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine the effect of selenium supplementation alone and of antioxidant mixtures with or without selenium on the risk of CVD, cancer, and mortality.
We identified studies using the Cochrane Library, Medline, and Embase for potential CVD outcomes, cancer, and all-cause mortality following selenium supplementation alone or after antioxidant supplement mixtures with and without selenium up to June 5, 2020. RCTs of ≥24 wk were included and data were analyzed using random-effects models and classified by the Grading of Recommendations, Assessment, Development, and Evaluation approach.
The meta-analysis identified 9423 studies, of which 43 were used in the final analysis. Overall, no association of selenium alone or antioxidants was seen with CVD and all-cause mortality. However, a decreased risk with antioxidant mixtures was seen for CVD mortality when selenium was part of the mix (RR: 0.77; 95% CI: 0.62, 0.97; P = 0.02), with no association when selenium was absent. Similarly, when selenium was part of the antioxidant mixture, a decreased risk was seen for all-cause mortality (RR: 0.90; 95% CI: 0.82, 0.98; P = 0.02) as opposed to an increased risk when selenium was absent (RR: 1.09; 95% CI: 1.04, 1.13; P = 0.0002).
The addition of selenium should be considered for supplements containing antioxidant mixtures if they are to be associated with CVD and all-cause mortality risk reduction. This trial was registered at https://www.crd.york.ac.uk/PROSPERO/ as CRD42019138268.
Obesity, diabetes, and cardiovascular disease (CVD) present important unmet prevention and treatment challenges. Dietary pulses are sustainable, affordable, and nutrient‐dense foods that have shown a ...wide range of health benefits in the prevention and management of these conditions. Despite these findings, recommendations for pulse intake continue to vary across chronic disease guidelines, and intake levels continue to remain low. Here, we summarize findings from recent systematic reviews and meta‐analyses assessing the relationship between dietary pulse consumption and cardiometabolic health and assess the overall strength of the evidence using the Grading of Recommendations, Assessment, Development, and Evaluation tool. We conclude that systematic reviews and meta‐analyses of prospective cohort studies assessing the relationship between legumes and the risk of coronary heart disease appear to provide moderate‐quality evidence of a benefit, and several systematic reviews and meta‐analyses of randomized controlled trials assessing the effect of pulses on cardiometabolic risk factors provide low‐ to moderate‐quality evidence of a benefit. There remains an urgent need, however, for more high‐quality prospective cohort studies and large, high‐quality, randomized trials to clarify the benefits of dietary pulses in the prevention and management of overweight/obesity, diabetes, and CVD.
The authors identified individual randomized controlled trials from previous meta-analyses and additional searches, and then performed meta-analyses on cardiovascular disease outcomes and all-cause ...mortality. The authors assessed publications from 2012, both before and including the U.S. Preventive Service Task Force review. Their systematic reviews and meta-analyses showed generally moderate- or low-quality evidence for preventive benefits (folic acid for total cardiovascular disease, folic acid and B-vitamins for stroke), no effect (multivitamins, vitamins C, D, β-carotene, calcium, and selenium), or increased risk (antioxidant mixtures and niacin with a statin for all-cause mortality). Conclusive evidence for the benefit of any supplement across all dietary backgrounds (including deficiency and sufficiency) was not demonstrated; therefore, any benefits seen must be balanced against possible risks.
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First defined in the mid-1990s, prebiotics, which alter the composition and activity of gastrointestinal (GI) microbiota to improve health and well-being, have generated scientific and consumer ...interest and regulatory debate. The Life Sciences Research Organization, Inc. (LSRO) held a workshop, Prebiotics and the Health Benefits of Fiber: Future Research and Goals, in February 2011 to assess the current state of the science and the international regulatory environment for prebiotics, identify research gaps, and create a strategy for future research. A developing body of evidence supports a role for prebiotics in reducing the risk and severity of GI infection and inflammation, including diarrhea, inflammatory bowel disease, and ulcerative colitis as well as bowel function disorders, including irritable bowel syndrome. Prebiotics also increase the bioavailability and uptake of minerals and data suggest that they reduce the risk of obesity by promoting satiety and weight loss. Additional research is needed to define the relationship between the consumption of different prebiotics and improvement of human health. New information derived from the characterization of the composition and function of different prebiotics as well as the interactions among and between gut microbiota and the human host would improve our understanding of the effects of prebiotics on health and disease and could assist in surmounting regulatory issues related to prebiotic use.
To determine the association of total and added fructose-containing sugars on cardiovascular (CVD) incidence and mortality.
MEDLINE, EMBASE and Cochrane Library were searched from January 1, 1980, to ...July 31, 2018. Prospective cohort studies assessing the association of reported intakes of total, sucrose, fructose and added sugars with CVD incidence and mortality in individuals free from disease at baseline were included. Risk estimates were pooled using the inverse variance method, and dose-response analysis was modeled.
Eligibility criteria were met by 24 prospective cohort comparisons (624,128 unique individuals; 11,856 CVD incidence cases and 12,224 CVD mortality cases). Total sugars, sucrose, and fructose were not associated with CVD incidence. Total sugars (risk ratio, 1.09 95% confidence interval, 1.02 to 1.17) and fructose (1.08 1.01 to 1.15) showed a harmful association for CVD mortality, there was no association for added sugars and a beneficial association for sucrose (0.94 0.89 to 0.99). Dose-response analyses showed a beneficial linear dose-response gradient for sucrose and nonlinear dose-response thresholds for harm for total sugars (133 grams, 26% energy), fructose (58 grams, 11% energy) and added sugars (65 grams, 13% energy) in relation to CVD mortality (P<.05). The certainty of the evidence using GRADE was very low for CVD incidence and low for CVD mortality for all sugar types.
Current evidence supports a threshold of harm for intakes of total sugars, added sugars, and fructose at higher exposures and lack of harm for sucrose independent of food form for CVD mortality. Further research of different food sources of sugars is needed to define better the relationship between sugars and CVD. REGISTRATION: clinicaltrials.gov, NCT01608620.
Adverse associations of low- and no-calorie sweetened beverages (LNCSB) with cardiometabolic outcomes in observational studies may be explained by reverse causality and residual confounding.
To ...address these limitations we used change analyses of repeated measures of intake and substitution analyses to synthesize the association of LNCSB with cardiometabolic outcomes.
MEDLINE, Embase, and the Cochrane Library were searched up to 10 June 2021 for prospective cohort studies with ≥1 year of follow-up duration in adults.
Outcomes included changes in clinical measures of adiposity, risk of overweight/obesity, metabolic syndrome, type 2 diabetes (T2D), cardiovascular disease, and total mortality.
Two independent reviewers extracted data, assessed study quality, and assessed certainty of evidence using GRADE. Data were pooled with a random-effects model and expressed as mean difference (MD) or risk ratio (RR) and 95% CI.
A total of 14 cohorts (416,830 participants) met the eligibility criteria. Increase in LNCSB intake was associated with lower weight (5 cohorts, 130,020 participants; MD -0.008 kg/year 95% CI -0.014, -0.002). Substitution of LNCSB for sugar-sweetened beverages (SSB) was associated with lower weight (three cohorts, 165,579 participants; MD, -0.12 -0.14, -0.10, kg/y) and lower incidence of obesity (OB) (one cohort, 15,765 participants; RR 0.88 95% CI 0.88, 0.89), coronary heart disease (six cohorts, 233,676 participants; 0.89 0.81, 0.98), cardiovascular disease mortality (one cohort, 118,363 participants; 0.95 0.90, 0.99), and total mortality (one cohort, 118,363 participants; 0.96 0.94, 0.98) with no adverse associations across other outcomes. Substitution of water for SSB showed lower weight (three cohorts, 165,579 participants; MD -0.10 kg/year -0.13, -0.06), lower waist circumference (one cohort, 173 participants; -2.71 cm/year -4.27, -1.15) and percent body fat (one cohort, 173 participants; -1.51% per year -2.61, -0.42), and lower incidence of OB (one cohort, 15,765 participants; RR 0.85 0.75, 0.97) and T2D (three cohorts, 281,855 participants; 0.96 0.94, 0.98). Substitution of LNCSB for water showed no adverse associations.
The evidence was low to very low certainty owing to downgrades for imprecision, indirectness, and/or inconsistency.
LNCSB were not associated with cardiometabolic harm in analyses that model the exposure as change or substitutions. The available evidence provides some indication that LNCSB in their intended substitution for SSB may be associated with cardiometabolic benefit, comparable with the standard of care, water.
Combined low-risk lifestyle behaviors (LRLBs) have been associated with a reduction in type 2 diabetes risk. This relationship has not been systematically quantified.
A systematic review and ...meta-analysis was conducted to assess the association of combined LRLBs with type 2 diabetes. Databases were searched up to September 2022. Prospective cohort studies reporting the association between a minimum of three combined LRLBs (including healthy diet) with incident type 2 diabetes were included. Independent reviewers extracted data and assessed study quality. Risk estimates of extreme comparisons were pooled using a random-effects model. Global dose-response meta-analysis (DRM) for maximum adherence was estimated using a one-stage linear mixed model. The certainty of the evidence was assessed using GRADE (Grading of Recommendations, Assessment, Development and Evaluations).
Thirty cohort comparisons (n = 1,693,753) involving 75,669 incident type 2 diabetes cases were included. LRLBs, with author-defined ranges, were healthy body weight, healthy diet, regular exercise, smoking abstinence or cessation, and light alcohol consumption. LRLBs were associated with 80% lower risk of type 2 diabetes (relative risk RR 0.20; 95% CI 0.17-0.23), comparing the highest with lowest adherence. Global DRM for maximum adherence to all five LRLBs reached 85% protection (RR 0.15; 95% CI 0.12-0.18). The overall certainty of the evidence was graded as high.
There is a very good indication that a combination of LRLBs that includes maintaining a healthy bodyweight, healthy diet, regular exercise, smoking abstinence or cessation, and light alcohol consumption is associated with a lower risk of incident type 2 diabetes.
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