Vegetarian Dietary Patterns and Cardiometabolic Risk in People With or at High Risk of Cardiovascular Disease

Abstract

IMPORTANCEPlant-based diets are known to improve cardiometabolic risk in the general population, but their effects on people at high risk of cardiovascular diseases (CVDs) remain inconclusive.OBJECTIVETo assess the association of vegetarian diets with major cardiometabolic risk factors, including low-density lipoprotein cholesterol (LDL-C), hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and body weight in people with or at high risk of CVDs.DATA SOURCESThis meta-analysis was registered before the study was conducted. Systematic searches performed included Embase, MEDLINE, CINAHL, and CENTRAL from inception until July 31, 2021.STUDY SELECTIONEligible randomized clinical trials (RCTs) that delivered vegetarian diets in adults with or at high risk of CVDs and measured LDL-C, HbA1c or SBP were included. Of the 7871 records screened, 29 (0.4%; 20 studies) met inclusion criteria.DATA EXTRACTION AND SYNTHESISTwo reviewers independently extracted data including demographics, study design, sample size, and diet description, and performed risk of bias assessment. A random-effects model was used to assess mean changes in LDL-C, HbA1c, SBP, and body weight. The overall certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool.MAIN OUTCOMES AND MEASURESMean differences between groups in changes (preintervention vs postintervention) of LDL-C, HbA1c, and SBP; secondary outcomes were changes in body weight and energy intake.RESULTSTwenty RCTs involving 1878 participants (range of mean age, 28-64 years) were included, and mean duration of intervention was 25.4 weeks (range, 2 to 24 months). Four studies targeted people with CVDs, 7 focused on diabetes, and 9 included people with at least 2 CVD risk factors. Overall, relative to all comparison diets, meta-analyses showed that consuming vegetarian diets for an average of 6 months was associated with decreased LDL-C, HbA1c, and body weight by 6.6 mg/dL (95% CI, −10.1 to −3.1), 0.24% (95% CI, −0.40 to −0.07), and 3.4 kg (95% CI, −4.9 to −2.0), respectively, but the association with SBP was not significant (−0.1 mm Hg; 95% CI, −2.8 to 2.6). The GRADE assessment showed a moderate level of evidence for LDL-C and HbA1c reduction.CONCLUSIONS AND RELEVANCEIn this study, consuming a vegetarian diet was associated with significant improvements in LDL-C, HbA1c and body weight beyond standard therapy in individuals at high risk of CVDs. Additional high-quality trials are warranted to further elucidate the effects of healthy plant-based diets in people with CVDs.

Cardiovascular Disease Risk in Individuals Following Plant-Based Dietary Patterns Compared to Regular Meat-Eaters

“…Non-HDL-C, TC and LDL-C concentrations were significantly higher in the RMEs compared to vegans. Metaanalysis of twenty RCTs showed that consuming a vegetarian (including vegan) dietary pattern was associated with a 0.4 mmol/L reduction in LDL-C compared to RMEs [47]. Another meta-analysis of 30 RCTs illustrated that the vegetarian (including vegan) dietary pattern is associated with reduced TC (−0.34 mmol/L) and LDL-C (−0.30 mmol/L) compared with RMEs [48].…”

The Impact of Stress and Social Determinants on Diet in Cardiovascular Prevention in Young Women

“…A recent meta-analysis on the vegetarian diet found that consuming a vegetarian diet was associated with significant improvements in low-density lipoprotein cholesterol (LDL-C), glycated hemoglobin (HbA1c), and body weight beyond the standard therapy in individuals at high risk of CVDs. However, the changes in LDL-C and HbA1c did not reach the clinical significance as per the cutoff target [74]. Few studies have been conducted on the effects of a vegetarian diet on cardiovascular risk in primary prevention.…”

Exploring Benefits and Barriers of Plant-Based Diets: Health, Environmental Impact, Food Accessibility and Acceptability

“…Papamichou et al (2019), reported reduction in HbA1c levels from adherence to vegetarian and Mediterranean dietary patterns on type 2 diabetes prevention and treatment [52]. Wang et al (2023) [53] found higher improvements in HbA1c levels from vegetarian diets compared to actual and conventional energy-restricted diets related to diabetes [53]. Moreover, a systematic review by Toumpanakis et al (2018) [51] on adults with type 2 diabetes found PBDs significantly improved HbA1c levels when compared to dietary guidelines for diabetes.…”