Vegetarian Nutrition (VN) for Disease Management (2023-24)
Vegetarian Nutrition for Disease Management Systematic Review
Lifestyle behaviors, including dietary patterns, play an important role in the management of cardiometabolic risk factors, cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). CVD and T2DM pose a significant global health burden. Vegetarian dietary patterns, including vegan diets, have been suggested as a healthy option to reduce dietary fats and cholesterol while providing cardiovascular health-promoting foods rich in dietary fiber, antioxidants, and phytochemicals. However, poorly planned vegetarian dietary patterns can limit intake of specific nutrients which can contribute to increased CVD risk. A vegetarian dietary pattern is one that does not include intake of flesh products such as meat, poultry or fish, and a vegan diet additionally does not include other animal products such as dairy products or eggs. Understanding the benefits and risks of vegetarian and vegan diets for adults with CVD risk factors, CVD and T2DM can help inform nutrition practitioners working with clients with these conditions who follow or are interested in following vegetarian or vegan diets.
A systematic review of randomized controlled trials (RCTs) was conducted to answer the research question: In adults with CVD risk factors (e.g., overweight/obesity, dyslipidemia, hypertension), CVD or T2DM, what are the effects of vegetarian diets on disease-specific outcomes of interest, including:
CVD Risk Factors
- Disease incidence: T2DM, CVD, hypertension, cardiovascular Events
- Mortality
- Blood pressure
- Lipid profile: LDL, HDL, and total cholesterol and triglyceride concentrations
- Body mass index (BMI), percent weight loss
- Glucose levels, HbA1c
Type 2 Diabetes Mellitus
- Disease Incidence: CVD, hypertension, cardiovascular events, kidney disease, retinopathy
- Mortality
- Diabetes medication/change
- Glycemic outcomes: HbA1c, fasting blood glucose, insulin levels, insulin sensitivity (HOMA-IR, HOMA2-IR)
- BMI, LDL-Cholesterol
Cardiovascular Disease
- Cardiovascular events
- Mortality
- Lipid profile: LDL, HDL, and total cholesterol and triglyceride concentrations
- BMI, blood pressure, vitamin B12 concentrations
Key Findings:
- The systematic review included and analyzed 27 randomized controlled trials published from 1998 until May 2023 examining the effect of vegetarian diets on adults with CVD risk factors (n=17), CVD (n=3) and/or T2DM (n=7).
- In adults with cardiovascular risk factors, primarily overweight or obesity, vegetarian or vegan diets likely reduce BMI compared to therapeutic or non-therapeutic non-vegetarian diets.
- In adults with cardiovascular risk factors, vegetarian diets may be equal in efficacy to therapeutic non-vegetarian diets in reducing fasting blood glucose concentrations.
- In adults with T2DM, vegetarian and vegan diets likely reduce HbA1c and BMI compared to therapeutic or non-therapeutic non-vegetarian diets.
- In adults with T2DM, though evidence was mixed, it does suggest a benefit of vegetarian diets on diabetes medication needs compared to therapeutic or non-therapeutic non-vegetarian diets.
- In adults with CVD, vegetarian including vegan diets may have no effect on blood pressure, lipid profile, quality of life or cardiovascular events or mortality compared to therapeutic or non-therapeutic non-vegetarian diets.
Use the links on the left to access the results of the systematic review.
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