Hello! Welcome to learning about plant-based eating! I have an interest in understanding how nutrition connects our mind and body, and what better way to dive deeper into this than reviewing the benefits of plant-based eating. I hope to enlighten you with this short review on the holistic advantages of eating plant-based, and how amazing food can be!

Introduction:

Plant-based diets are becoming increasingly popular in Western societies in part due to the increased knowledge of the health benefits, as well as their positive environmental impact. I recently watched “You Are What You Eat”, a Netflix documentary following twins, one of whom eats a vegan diet (no animal products), and one who eats an omnivorous diet (plant and animal products) which truly opened my eyes to the holistic benefits of plant-based eating. This summary will follow various systematic reviews that have explored the potential benefits of plant-based diets on metabolism, cognition, disease prevention and overall holistic well-being.

Studies:

The first robust systematic review was published by Medawar et al. (2019) in Translational Psychiatry, aimed at investigating the short- to moderate-term effects of plant-based diets compared to conventional diets, and how they impact weight status, energy metabolism, and systemic inflammation in healthy individuals, obese individuals, and type-2 diabetes patients. The review analyzed 32 studies, including randomized controlled trials and observational studies.

The second review, by Wang et al., (2023), evaluated vegetarian and vegan diets, looking at the benefits and drawbacks of both. This review examined similar variables in prospective studies and randomized clinical trials, such as metabolism, oxidative stress, inflammation, hypertension, gut microbiome, diabetes, heart disease, cancer, dementia and more. This review examines both sides of the argument which is appreciated.

Results:

Medawar et al. Review (2019)

The first review found that that plant-based diets compared to omnivorous (meat eating) can have a positive impact on decreasing body weight, blood pressure, lipid levels and inflammation. Specifically, lower glucose-level markers, decreased low- density (LDL) and high density-lipoproteins (HDL) and total cholesterol (TC), and increased insulin sensitivity, proposing plant based eating may have diabetes-preventative potential. Those who followed a vegan diet showed higher weight loss and improved metabolic status. Plant-based diets are rich in anti-inflammatory molecules, in contrast to animal products that contain numerous proinflammatory molecules, which increase the risk for heart disease and might also directly affect healthy brain ageing.

Additionally, a novel finding included positive impacts on the gut microbiome metabolism, which is highly correlated to an abundance of bodily functions (metabolism and brain function). Vegan diets were found to have lower intake of saturated fatty acids, vitamin B12, calcium, zinc and protein, however higher intake of fiber, magnesium, iron, folic acid, vitamin B1, C and E, which could induce the beneficial metabolism effects and weight loss. Higher fiber diets are especially positively linked to improved metabolism, appetite regulation, and might prevent chronic disease such as obesity and type 2 diabetes through slowing digestion and improving lipid control.

While evidence for cognitive and metal effects is still inconclusive, due to limited studies, there is promise in understanding how plant-based diets may affect the microbiome-gut- brain axis. The interaction between our nutrition and the brain cannot go unnoticed, and there is potential here to see how diet impacts brain activity, brain metabolism, disease progression, and mood (including mood disorder treatments).

Wang et al. Review (2023)

Wang and colleagues found very similar results on the numerous positive impacts of plant-based eating, which further corroborates the importance of this knowledge. This review distinguishes between healthy vegetarian diets and unhealthy vegetarian diets, where the nutritional benefits come from, healthy vegetarian diets including complex fiber-rich carbohydrates, vitamins and antioxidants, monounsaturated fatty acids (aka good fats, olive oil/avocado/nuts/etc.), polyunsaturated fats (nuts, tofu, soybeans, etc.), potassium, magnesium, selenium.

This study confirms plant-based eating, vegetarian specifically, has protective effects for the prevention of diabetes, high cholesterol, hypertension, and obesity. Several factors from plant based eating have been hypothesized to play a role, similarly to the other review. These include the way vegetarian and vegan diets can lower lipids, lower blood glucose, increase insulin sensitivity, lower oxidative stress, inflammation, and hypertension, and increase gut-health that further improves the body’s metabolism.

Potential Risks

The discourse around plant based eating often comes from the worry vegetarian and vegan diets do not provide the necessary micronutrients the same way omnivorous diets do. While there is a risk of being deficient in B12, iron, zinc, calcium, if individuals are monitoring vitamin/mineral intake, eating a variety of different foods, and if needed, taking a supplement, these worries should not discourage anyone from not eating a plant-based diet. Many fruits and vegetables have an abundance of protein, vitamins, and minerals, and some that are even more available to be absorbed from the body than animal products.

Conclusion

Overall, both reviews provide robust and strong evidence for the beneficial effects of plant-based diets on the body and potentially brain outcomes, as well as protective effects against chronic disease. While more research is needed to fully understand the mechanisms behind these effects, the findings suggest that plant-based diets can be an effective strategy for improving health and reducing the risk of chronic diseases such as type 2 diabetes, obesity, cardiovascular disease, hypertension, etc.

Always make sure you are consulting a medical professional to ensure you’re meeting your nutritional needs, but, with the right guidance and support, a plant-based diet can be a delicious and nutritious way to improve your health and wellbeing.

References

1. Medawar, E., Huhn, S., Villringer, A., & Veronica Witte, A. (2019). The effects of plant-based diets on the body and the brain: a systematic review. Translational psychiatry, 9(1), 226. https://doi.org/10.1038/s41398-019-0552-0
2. Wang, T., Masedunskas, A., Willett, W. C., & Fontana, L. (2023). Vegetarian and vegan diets: benefits and drawbacks. European heart journal, 44(36), 3423–3439. https://doi.org/10.1093/eurheartj/ehad436