Available online 8 May 2024

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70% of Americans qualify as overweight or obese, with these numbers only expected to rise.

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Plant-based diets (PBDs) are a characterized by the consumption of plant-based foods and low intake of animal protein or products, such as vegan and vegetarian.

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Our review showed PBDs are an effective diet for weight loss intervention, with an average of 5.0kg weight loss, and further weight loss achieved with longer duration.

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PBDs promote higher intake of fiber and consist of “high-bulk, low-calorie density” foods, which help weight loss maintenance by increasing satiety and reducing hunger.

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Adopting the COACH (Curious, Open-minded, Appreciative, Compassionate, Honest) approach, helping patients establish SMART (Specific, Measurable, Action-oriented, Realistic, Timely) goals, and establishing shared medical appointments (SMAs) can help patients adopt a PBD.

ABSTRACTObjective

Obesity is the most prevalent chronic disease in the United States with over 70% of the American population suffering from overweight/obesity. Recently, the popularity of plant-based diets has grown, with individuals adopting these diets for ethical, health and environmental reasons. Our aim is to evaluate the effect of a plant-based diet (PBD) on weight loss among patients who are overweight or obese.

Methods

A literature review of PBDs for the treatment of obesity was conducted using PubMed and Scopus. Our search yielded 27 intervention trials (3361 participants) and six metanalyses (9168 participants, 61 trials).

Results

Among the intervention trials evaluated, 75% showed a significant decrease in weight loss in the intervention group, on average -5.0kg (range -1.8 to -12.1kg). Other outcomes included energy intake (-420 Kcal/day), systolic blood pressure (-3.78 mmHg), fasting plasma glucose (-2.0 mmol/L), HbA1c (-0.5%, -3.4 mmol/L), total cholesterol (-0.40 mmol/L), low-density lipoprotein (-0.38 mmol/L), triglyceride levels (+0.13 mmol/L), and fiber intake (+10.8 g/day). The six meta-analyses showed weight loss (average -2.9 kg , range -2.02 kg to -4.1 kg), BMI reduction, and improvements in HbA1c, LDL, and total cholesterol.

Conclusion

PBDs result in significant weight loss and improve metabolic outcomes. PBDs offer a sustainable approach to long-term weight loss maintenance. Healthcare providers should encourage open discussions with their patients regarding their dietary habits to assist them in setting feasible lifestyle goals and consider shared medical appointments to support patients in transitioning to PBDs.

Section snippetsINTRODUCTION

The obesity epidemic in the United States is a growing public health concern, with as much as 70% of the population qualifying as overweight or obese.1 Obesity is the most common chronic disease in the United States.2 Patients with obesity or overweight are at an increased risk of various complications, including hypertension, diabetes, sleep apnea, hyperlipidemia, osteoarthritis, myocardial infarction, stroke, and cancer.2,3 It is a significant health burden, as individuals with obesity are at

METHODS

With the guidance of a biomedical science reference librarian, a literature review of plant-based diets for the treatment of obesity was conducted using PubMed and Scopus as data sources. English-language trials and reviews with weight loss as the primary outcome and published between January 1, 2000 and November 14, 2023 were reviewed. Full search terms available upon request. Article title and abstracts were screened and then reviewed by two of the authors (Figure 1). Information from each

RESULTS

The 27 intervention trials reviewed involved 3361 participants, with an average 131 participants per study, ranging from 20 to 389 participants. Study types included 17 randomized control trials, 3 randomized crossover trials, 1 nonrandomized control trial and 6 uncontrolled interventions. Intervention duration ranged from 2 weeks to 104 weeks (average 24 weeks), and participant’s average age was 52.7 years (range 40-59). Diverse population characteristics were observed, with some studies

DISCUSSION

Studies have shown an increasing trend towards reducing meat consumption in the U.S. and the U.S. Department of Agriculture recommends a “Healthy Vegetarian Dietary Pattern” as one of the three dietary patterns which avoid overconsumption of unhealthful foods and meet nutrient needs without exceeding calorie requirements.46,47 With this growing interest and support for PBDs, the aim of this review was to evaluate the effect of PBDs on patients with overweight or obesity.

Based on the results of

Conclusion

Obesity is the most common chronic disease in the United States and over 70% of the American population suffers from overweight/obesity. While there are multiple determinants of weight, such as genetics and socioeconomic factors, lifestyle, particularly diet, plays an essential role in reducing the incidence of and managing obesity. The results of this review show a significant weight loss following a plant-based diet, along with signs of improvement in metabolic outcomes like blood pressure,

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© 2024 Published by Elsevier Inc. on behalf of the AACE.