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Diabetology & Metabolic Syndrome Aug 2022A vegan diet has benefits on weight reduction and on the parameters of glucose and lipid metabolism. This meta-analysis aimed to investigate the efficacy of plant-based...
BACKGROUND
A vegan diet has benefits on weight reduction and on the parameters of glucose and lipid metabolism. This meta-analysis aimed to investigate the efficacy of plant-based diets on insulin resistance and blood lipids in patients with obesity.
METHODS
PubMed, Embase, and the Cochrane Library were searched for available papers published up to March 2021. The primary outcome was insulin resistance which was assessed by Homeostasis Model Assessment Insulin Resistance (HOMA-IR), other metabolic parameters measures including the pre/post-diet changes in triglycerides, HDL-cholesterol, total cholesterol, LDL-cholesterol. All analyses were performed using the random-effects model.
RESULTS
Six studies (seven datasets) were included. Compared with baseline, the plant-based diet improved the HOMA-IR (SMD = 1.64, 95%CI 0.95, 2.33; I = 91.8%, P < 0.001), total cholesterol (SMD = 2.51, 95% CI 0.88, 4.13; I = 98.0%, P < 0.001), HDL-cholesterol (SMD = 1.55, 95% CI 0.66, 2.44; I = 92.0%, P < 0.001), and LDL-cholesterol (SMD = 2.50, 95% CI 1.30, 3.70; I = 94.4%, P < 0.001), but not the triglycerides (SMD = - 0.62, 95% CI - 1.92, 0.68; I = 97.8%, P < 0.001). The sensitivity analyses showed that the results were robust.
CONCLUSIONS
In obese individuals with insulin resistance, a vegan diet improves insulin resistance and dyslipidemia, except for triglycerides.
PubMed: 35964120
DOI: 10.1186/s13098-022-00879-w -
PloS One 2023Nutrition affects both physical and mental health but evidence is mixed regarding potential associations between anxiety and diet, particularly dairy consumption. We...
BACKGROUND
Nutrition affects both physical and mental health but evidence is mixed regarding potential associations between anxiety and diet, particularly dairy consumption. We conducted a systematic literature review (SLR) of dairy consumption and/or various dietary patterns and risk of anxiety.
METHODS
Literature searches were conducted in PubMed and Embase. All study designs except case reports, small case series, and SLRs were considered for inclusion. Reference lists of previously published SLRs were reviewed for any relevant additional studies. Studies of populations without dairy sensitivities exploring the association between dietary patterns and/or dairy consumption and anxiety published through May 2022 were identified using predefined eligibility criteria. Study quality was determined using the Academy of Nutrition and Dietetics Quality Criteria Checklist.
RESULTS
For this SLR, 132 studies were included; 80 were cross-sectional. Studies examined different dietary patterns (e.g., Mediterranean, gluten-free) and anxiety using various anxiety scales, with 19 studies specifically reporting on whole dairy consumption and anxiety. Dairy consumption was significantly associated with a lower risk of anxiety in 7 studies, while the remaining 12 studies showed no significant associations. Evidence was mixed for the association between various dietary patterns and anxiety, but more studies observed a lower risk of anxiety with greater adherence to "healthy" diets (e.g., Mediterranean, diet quality score, vegetarian/vegan) than a higher risk. Notable heterogeneity in study populations, time periods, geographical locations, dietary assessment methods, and anxiety scales was observed.
CONCLUSIONS
The results of this SLR suggest a potential link between diet including diary consumption and anxiety, but future studies, especially with longitudinal designs that measure diet and anxiety at several timepoints and comprehensively adjust for confounders, are needed to fully understand the relationship between diet and anxiety.
Topics: Humans; Diet; Anxiety; Anxiety Disorders; Feeding Behavior; Dietary Patterns
PubMed: 38153944
DOI: 10.1371/journal.pone.0295975 -
Prostate Cancer and Prostatic Diseases Sep 2022Plant-based diets are increasingly popular and have many well-established benefits for health and environmental sustainability. Our objective was to perform a systematic... (Review)
Review
BACKGROUND
Plant-based diets are increasingly popular and have many well-established benefits for health and environmental sustainability. Our objective was to perform a systematic review of plant-based diets and prostate cancer.
METHODS
We performed a systematic database and citation search in February 2022. Studies were included if they reported primary data on plant-based dietary patterns (i.e., vegan, vegetarian, plant-based) and incidence among at-risk men for prostate cancer, or oncologic, general health/nutrition, or quality of life outcomes among patients with prostate cancer or caregivers.
RESULTS
A total of 32 publications were eligible for the qualitative synthesis, representing 5 interventional and 11 observational studies. Interventional studies primarily focused on lifestyle modification including plant-based diets for men on active surveillance for localized prostate cancer or with biochemical recurrence after treatment, showing improvements in short-term oncologic outcomes alongside improvements in general health and nutrition. Observational studies primarily focused on prostate cancer risk, showing either protective or null associations for plant-based dietary patterns. Studies of the vegan diet consistently showed favorable associations with risk and/or outcomes. Gaps in the current literature include impact for long-term disease-specific outcomes.
CONCLUSIONS
Interventional studies showed generally favorable results of lifestyle modifications incorporating a plant-based diet with prostate cancer outcomes as well as improvements in nutrition and general health. Observational studies demonstrated either a lower risk of prostate cancer or no significant difference. These results are encouraging in light of the many benefits of plant-based diets for overall health, as well as environmental sustainability and animal welfare.
Topics: Diet; Diet, Vegan; Humans; Incidence; Life Style; Male; Prostatic Neoplasms; Quality of Life
PubMed: 35790788
DOI: 10.1038/s41391-022-00553-2 -
Nutrition Reviews May 2022Mental health may be influenced by some dietary patterns. Among common elements of beneficial patterns is high fruit and vegetable intake. However, no systematic review...
CONTEXT
Mental health may be influenced by some dietary patterns. Among common elements of beneficial patterns is high fruit and vegetable intake. However, no systematic review has been conducted to date, to our knowledge, that has assessed the influence of fruit and vegetable dietary patterns on a broad spectrum of mental health.
OBJECTIVE
We conducted a systematic review, using the PRISMA guidelines, of the observational studies analyzing the association between the dietary pattern of fruit and vegetables and the broad aspects of mental health in adult women.
DATA SOURCES
The databases PubMed and Web of Science were searched, and additional manual search for observational peer-reviewed studies was conducted for studies published until June 2019.
DATA EXTRACTION
A total of 5911 studies were extracted and verified based on title and abstract for the inclusion criteria. All procedures were conducted independently by 2 researchers. The final number of included studies was 30. The review was structured around the type of observed outcome.
DATA ANALYSIS
The included studies had defined habitual intake associated with dietary patterns with the intake of specific fruit and/or vegetables, and/or fruit or vegetable products (eg, juices), as well as any aspect of the broad spectrum of general mental health. The Newcastle-Ottawa Scale was used to assess bias. The observed association was not stated in all the included studies; some of them revealed a reverse relationship, but only for the vegetarian/vegan diet. A vegetarian diet may be characterized by high consumption of fruits and vegetables, but it sometimes may not be properly balanced, due to excluded products. This may be the reason of observed situation.
CONCLUSIONS
A general positive influence was observed for the dietary patterns characterized by high consumption of fruit and vegetables and of fruit or vegetable products by women.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO registration no. CRD42019138148.
Topics: Adult; Diet; Diet, Vegetarian; Female; Fruit; Humans; Mental Health; Vegetables
PubMed: 34041545
DOI: 10.1093/nutrit/nuab007 -
International Journal of Obesity (2005) Oct 2023It is unknown whether vegetarian diets (VDs) may improve outcomes in people with overweight and obesity. (Meta-Analysis)
Meta-Analysis Review
Vegetarian diets on anthropometric, metabolic and blood pressure outcomes in people with overweight and obesity: a systematic review and meta-analysis of randomized controlled trials.
BACKGROUND
It is unknown whether vegetarian diets (VDs) may improve outcomes in people with overweight and obesity.
OBJECTIVE
To systematically assess the effects of VDs vs. omnivore diets on anthropometric, metabolic, and blood pressure outcomes in people with overweight and obesity.
METHODS
We searched for randomized controlled trials (RCTs) in EMBASE, PubMed, Web of Science, and Scopus until February 2, 2022. Primary outcomes were anthropometric risk factors (weight, body mass index [BMI], waist circumference [WC], hip circumference [HC], and body fat percentage). Secondary outcomes were metabolic risk factors (fasting serum glucose, HbA1c, insulin levels) and blood pressure (systolic blood pressure [SBP], diastolic blood pressure [DBP]). Random-effects meta-analyses were performed and effects were expressed as mean difference (MD) and their 95% confidence intervals (CI). The quality of evidence was assessed using GRADE methods.
RESULTS
Nine RCTs (n = 1628) were included. VDs decreased weight (MD -3.60 kg, 95%CI -4.75 to -2.46) and glucose (MD -10.64 mg/dL, 95%CI -15.77 to -5.51), but did not decrease WC (MD -3.00 cm, 95%CI -6.20 to 0.20), BMI (MD -0.87 kg/m2, 95%CI -1.80 to 0.06), or HC (MD: -0.86 cm, 95%CI -3.46 to 1.74). VDs did not decrease HbA1c (MD -0.40%, 95%CI -0.89 to 0.10), insulin (MD -3.83 mU/L, 95%CI -8.06 to 0.40), SBP (MD -0.25 mmHg, 95%CI -2.58 to 2.07), or DBP (MD -1.57 mmHg, 95%CI -3.93 to 0.78). Subgroup analyses by type of VD (four RCTs evaluated lacto-ovo-vegetarian diets and five RCTs vegan diets) showed similar results to the main analyses. QoE was very low for most of the outcomes.
CONCLUSIONS
In comparison to an omnivorous diet, VDs may reduce weight and glucose, but not blood pressure or other metabolic or anthropometric outcomes. However, the QoE was mostly very low. Larger RCTs are still needed to evaluate the effects of VD on anthropometric, metabolic factors, and blood pressure in people with overweight and obesity.
Topics: Humans; Overweight; Glycated Hemoglobin; Randomized Controlled Trials as Topic; Obesity; Diet, Vegetarian; Glucose; Insulins
PubMed: 37528197
DOI: 10.1038/s41366-023-01357-7 -
Nutrition Reviews Sep 2017Although a recent meta-analysis of randomized controlled trials showed that adoption of a vegetarian diet reduces plasma lipids, the association between vegetarian diets... (Meta-Analysis)
Meta-Analysis Review
CONTEXT
Although a recent meta-analysis of randomized controlled trials showed that adoption of a vegetarian diet reduces plasma lipids, the association between vegetarian diets and long-term effects on plasma lipids has not been subjected to meta-analysis.
OBJECTIVE
The aim was to conduct a systematic review and meta-analysis of observational studies and clinical trials that have examined associations between plant-based diets and plasma lipids.
DATA SOURCES
MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for articles published in English until June 2015.
STUDY SELECTION
The literature was searched for controlled trials and observational studies that investigated the effects of at least 4 weeks of a vegetarian diet on plasma lipids.
DATA EXTRACTION
Two reviewers independently extracted the study methodology and sample size, the baseline characteristics of the study population, and the concentrations and variance measures of plasma lipids. Mean differences in concentrations of plasma lipids between vegetarian and comparison diet groups were calculated. Data were pooled using a random-effects model.
RESULTS
Of the 8385 studies identified, 30 observational studies and 19 clinical trials met the inclusion criteria (N = 1484; mean age, 48.6 years). Consumption of vegetarian diets was associated with lower mean concentrations of total cholesterol (-29.2 and -12.5 mg/dL, P < 0.001), low-density lipoprotein cholesterol (-22.9 and -12.2 mg/dL, P < 0.001), and high-density lipoprotein cholesterol (-3.6 and -3.4 mg/dL, P < 0.001), compared with consumption of omnivorous diets in observational studies and clinical trials, respectively. Triglyceride differences were -6.5 (P = 0.092) in observational studies and 5.8 mg/dL (P = 0.090) in intervention trials.
CONCLUSIONS
Plant-based diets are associated with decreased total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol, but not with decreased triglycerides.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO number CRD42015023783. Available at: https://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42015023783.
Topics: Cholesterol, HDL; Cholesterol, LDL; Databases, Factual; Diet, Vegan; Diet, Vegetarian; Humans; Observational Studies as Topic; Randomized Controlled Trials as Topic; Triglycerides
PubMed: 28938794
DOI: 10.1093/nutrit/nux030 -
Nutrients Nov 2021Kidney stone disease (KSD) has a strong association with diet metabolic syndrome. This review aims at exploring the lithogenic risk posed by the current most popular...
OBJECTIVES
Kidney stone disease (KSD) has a strong association with diet metabolic syndrome. This review aims at exploring the lithogenic risk posed by the current most popular diets. Our approach was to search for the effect of each diet type on the major urinary risk factors, to try to draw conclusions regarding the association of a specific diet type and KSD.
METHODS
This systematic review searched for the available literature exploring the association between the existing popular fad diets and KSD. Articles in English, French and Spanish were included, without restriction of the search period with the final search done in August 2021.
RESULTS
Total number of studies and studies for each diet type was as follows: 22 articles for the low carbohydrate diet, 20 articles for high protein diets, 26 articles for vegetarian and vegan diets. There exists a substantial variability in different low carbohydrate and high protein diets, and considerable overlap between modern popular fad diets. High carbohydrate intake might increase urine uric acid, calcium and oxalate levels. High protein diets increase urine calcium and uric acid and lower urine pH and citrate. Consumption of fruits and vegetables increases the urinary volume and urinary citrate. In vegan diets, sufficient daily calcium intake is important to avoid possible secondary hyperoxaluria.
CONCLUSIONS
Few studies evaluated the direct relationship between modern fad diets and KSD. In general, the reduction of carbohydrate in the diet, and counterbalancing protein rich diets with sufficient intake of fruits and vegetables, seem to play a protective role against KSD formation. Maintaining sufficient calcium intake in vegan and vegetarian diets is important. Additional research is needed to directly evaluate the link between KSD and each diet type.
Topics: Calcium, Dietary; Diet Fads; Humans; Kidney Calculi
PubMed: 34959822
DOI: 10.3390/nu13124270 -
Scientific Reports Dec 2020Plant-based diets like vegetarian or vegan diets might influence circulating levels of inflammatory biomarkers, thereby reducing the risk of chronic diseases. This... (Comparative Study)
Comparative Study Meta-Analysis
Plant-based diets like vegetarian or vegan diets might influence circulating levels of inflammatory biomarkers, thereby reducing the risk of chronic diseases. This systematic review and meta-analysis aimed to investigate the associations of veganism and vegetarianism with circulating inflammatory biomarkers in comparison to omnivores. Literature search was conducted in Pubmed and EMBASE until April 2020 and mean differences of biomarkers were assessed for: C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-18 (IL-18), interleukin-1 receptor antagonist (IL-1 RA), tumor necrosis factor-alpha (TNF-ɑ), E-selectin, intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), adiponectin, omentin-1 and resistin. Of initially identified 1073 publications, 21 cross-sectional studies met the inclusion criteria and were included in the systematic review and meta-analysis. Vegan diet was associated with lower levels of CRP compared to omnivores [mean difference - 0.54 mg/l, 95%-CI: - 0.79 to - 0.28, p < 0.0001]. This association was less pronounced in vegetarians [mean difference - 0.25 mg/l, 95%-CI: - 0.49 to 0.00, p = 0.05]. In patients with impaired kidney function, the association between vegetarian nutrition and CRP was much stronger with - 3.91 mg/l (95%-CI: - 5.23 to - 2.60; p < 0.0001). No substantial effects were observed for all other inflammatory biomarkers. Despite strong associations between CRP and a vegan or vegetarian diet were seen, further research is needed, as most inflammatory biomarkers were investigated only in single studies so far.
Topics: Biomarkers; C-Reactive Protein; Chronic Disease; Diet, Vegan; Diet, Vegetarian; Inflammation; Inflammation Mediators; Interleukin 1 Receptor Antagonist Protein; Interleukin-18; Interleukin-6
PubMed: 33303765
DOI: 10.1038/s41598-020-78426-8 -
Joint Bone Spine Mar 2022This article presents the 1st set of dietary recommendations of the French Society for Rheumatology for patients suffering from chronic inflammatory rheumatic diseases...
This article presents the 1st set of dietary recommendations of the French Society for Rheumatology for patients suffering from chronic inflammatory rheumatic diseases (IRD) made by a working group consisting of 12 rheumatology experts, 3 physician nutrition specialists, 1 internal medicine specialist, 1 registered dietician and 3 representatives from patient associations. This group relied on a systematic literature review and on expert opinions, while taking into consideration not only the joint effects of diet in IRD but also the extra-articular ones. Eight general principles and nine recommendations were established. The general principles emphasize that nutritional advice is not a substitute for pharmacological treatment of IRD and that it is an integral part of the patients' overall care, which could help the patient actively participate in their care. The recommendations propose supporting weight loss in subjects who are overweight or obese, a Mediterranean-type diet and supplementation in polyunsaturated fatty acids, mainly omega-3. Conversely, gluten-free diets (in the absence of celiac disease), vegetarian/vegan diets, fasting and elimination of dairy products should not be proposed. Supplementation with vitamins or trace elements is not indicated for controlling chronic IRD activity, while the use of probiotics or spices is not recommended given the limited or disparate data.
Topics: Diet; Fatty Acids, Omega-3; Humans; Rheumatic Diseases; Rheumatology; Vitamins
PubMed: 34902577
DOI: 10.1016/j.jbspin.2021.105319 -
Eating and Weight Disorders : EWD Oct 2022Meat avoidance has long been thought to be related to eating psychopathology; however, research does not necessarily support this notion. Furthermore, commonly used... (Review)
Review
PURPOSE
Meat avoidance has long been thought to be related to eating psychopathology; however, research does not necessarily support this notion. Furthermore, commonly used eating disorder scales may be picking up on normal meat-avoiding behaviours in vegetarians and vegans. As such, we systematically reviewed the association between vegetarianism, veganism, and disordered eating, and reviewed the psychometric properties of eating disorder scales for use in these populations.
METHODS
We searched electronic databases MEDLINE, PsychINFO, and CINAHL for literature published until June 2021.
RESULTS
Forty-eight studies met eligibility criteria, with no consensus as to whether meat avoidance was associated with higher rates of disordered eating. Most studies reported a significant positive association with both vegetarianism and veganism, and orthorexia nervosa. Six studies provided evidence for the use of eating disorder measures in vegetarians and vegans, reporting poor psychometric fit among all scales.
CONCLUSION
This systematic review highlights the extent to which vegetarians and vegans have been highly understudied, with limited research suggesting higher levels of orthorexia nervosa behaviours in vegetarians and vegans. Furthermore, our results provide tentative evidence that the factorial validity of commonly used eating disorder scales, such as the EDE-Q, may be poor in vegans.
LEVEL OF EVIDENCE
Level I, systematic review.
Topics: Diet, Vegan; Feeding and Eating Disorders; Humans; Meat; Vegans; Vegetarians
PubMed: 35729472
DOI: 10.1007/s40519-022-01428-0