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February 24, 2021

Plant-Based Diets for Obesity Treatment

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Plant-based diet

Plant the seeds to your best life – plant-based diets for obesity treatment and/or prevention

If you are what you eat, how do you eat your way to your greatest self? 2020 is out, 2021 is in – it’s time to plant the seeds to living your best life after a tough year. Bye-bye, quarantine fifteen and stress eating. Hello, wellness warrior and plant-based diet – that’s right, based on current evidence, many nutrition experts recommend plant-based diets for obesity treatment and/or prevention1. In fact, vegetarian diets are one of the three healthy eating patterns recommended by the 2015–2020 Dietary Guidelines for Americans2. But that’s not all – plant based diets have been shown consistently to also improve cardiovascular health, as well as decrease risk for diseases like diabetes and cancer, and to top it off, be better for the environment1.

While all this sounds very exciting, let’s get into the nitty gritty of what exactly is a plant-based diet. Generally, this term can refer to a number of different eating patterns, ranging from vegan to all different types of vegetarian3.

  • Vegan diets – exclude all meat and animal products, which encompasses seafood, eggs, dairy and even honey.
  • Ovo-vegetarian diet – a vegetarian diet that includes eggs
  • Lacto-vegetarian diet – a vegetarian diet that includes dairy
  • Ovo-lacto-vegetarian diet – a vegetarian diet that includes both eggs and dairy
  • Pescatarian diet – a vegetarian diet that includes fish
  • Flexitarian or semi-vegetarian diet – focuses predominantly on plants, with occasional meat consumption

You may be wondering – with all these options, which plant-based diets are the most effective for weight loss and health?

Generally, studies show that vegan and ovo-lacto vegetarians lose more weight compared to pescetarians, semi-vegetarians and omnivores (those who eat everything)4. In fact, the ovo-lacto vegetarian diet is comparable to the much touted Mediterranean diet, for both weight loss and reduction of cardiovascular disease risk5. However, the ovo-lacto vegetarian diet works better on lowering LDL- or bad cholesterol, whereas the Mediterranean diet is superior in lowering triglyceride levels.

Enticed by these benefits but still too intimidated to make the switch? Try starting with these easy steps:

  1. Begin with incorporating just one or two plant-based meals into your week. Once you get used to it, you can gradually add more into your routine. Both ovo-lacto vegetarian and vegan diets are considered equally effective plant-based diets for obesity treatment, so choose based on what eating pattern you are able to maintain long-term4.
  2. Play with texture and color. Plant-based diets don’t have to be boring. The 2015–2020 Dietary Guidelines for Americans recommend a variety of different colored plant foods (encompassing grains, vegetables, fruits and nuts/seeds), divided over the course of the week2. The predominant vegetables should be red and orange (including winter squash, pumpkin and sweet potato), starchy (i.e. white potatoes, corn, green peas, green lima beans, plantains, and cassava), legumes (for instance, beans and peas) and other (such as iceberg lettuce, green beans, onions, cucumbers, cabbage, celery, zucchini, mushrooms, and green peppers). To a lesser extent, leafy greens are also recommended. Vegetables can be consumed either raw or cooked, and prepared from different formats including fresh, frozen, canned, dried or even juiced. If you need inspiration, here are 50 ideas to get you started, including options such as “very vegetable curry” and “red, white and blue salad”6.
  3. Can’t do it alone? Then do it with somebody else. Make a pact with a friend, coworker or family member, to switch to a plant-based diet together. Challenge each other to a friendly competition – who can do it better, develop tastier recipes, etc. If you don’t have anyone you know who wants to eat a plant-based diet, you can also find like-minded people and resources online (for example, check out expert-based:,7 or this website by three vegan/vegetarian friends: hurry the food up8).

Now that you are fired up and ready to take on the plant-based diet, there are a number of key things to remember so as to avoid being an obstacle to your own success:

  • Not all plant foods are healthy and help with weight loss. Many plant foods can be highly processed (such as potato chips and desserts) and contain unhealthy ingredients. Choose whole foods that are as minimally processed as possible, like whole grains as well as low-glycemic index fruits and vegetables.
  • Make sure to limit plant foods high in saturated fats, seeing as among the macronutrients, fats are comparatively higher in calories than carbohydrates and proteins3. However, this is not a license to consume as many carbohydrates as possible, as that can also lead to weight gain, so make sure to evaluate where the foods fall in terms of glycemic index (lower is better).
  • The exception to the rule is dietary fiber, a special type of carbohydrate that has been shown to help with weight loss9. Eating lots of dietary fiber can keep you full for longer, so that you consume less calories overall4.
  • It is better to get your fiber in whole plant foods rather than in supplement form, as studies have not shown benefit in weight loss with fiber supplements themselves – again highlighting the importance of eating whole foods10.

Finally, no matter what plant-based diet you choose to help with weight loss or to prevent weight gain, the key thing is that you find something that you can incorporate into your lifestyle, to maintain long term for optimal health and weight. It is a new year, with hopeful beginnings, so let’s shed the pandemic weight and plant the seeds to your best life!

(1) Academy of Nutrition and Dietetics. "Position of the Academy of Nutrition and Dietetics: Vegetarian Diets." J Acad Nutr Diet. 2016;116(12):1970-1980. (2) U.S. Department of Health and Human Services and U.S. Department of Agriculture. "2015 – 2020 Dietary Guidelines for Americans." 8th Edition. December 2015. (3) Tran E, Dale HF, Jensen C, Lied GA. "Effects of Plant-Based Diets on Weight Status: A Systematic Review." Diabetes Metab Syndr Obes. 2020 Sep 30;13:3433-3448. doi: 10.2147/DMSO.S272802. (4) Turner-McGrievy GM, Davidson CR, Wingard EE, Wilcox S, Frongillo EA. "Comparative effectiveness of plant-based diets for weight loss: a randomized controlled trial of five different diets." Nutrition. 2015;31(2):350–358. doi:10.1016/j.nut.2014.09.002 (5) Sofi F, Dinu M, Pagliai G, Cesari F, Gori AM, Sereni A, Becatti M, Fiorillo C, Marcucci R, Casini A. "Low-Calorie Vegetarian Versus Mediterranean Diets for Reducing Body Weight and Improving Cardiovascular Risk Profile: CARDIVEG Study (Cardiovascular Prevention With Vegetarian Diet)." Circulation. 2018 Mar 13;137(11):1103-1113. doi: 10.1161/CIRCULATIONAHA.117.030088. Epub 2018 Feb 26. (6) Dinner Tonight. "Vegetarian Recipes." Dinner Tonight: Texas A+M Agrilife extension. (7) "Eating Vegetarian." US department of agriculture. (8) Hurry the food up. Hurry the food up: vegetarian recipes for busy people. (9) Sylvetsky AC, Edelstein SL, Walford G, Boyko EJ, Horton ES, Ibebuogu UN, Knowler WC, Montez MG, Temprosa M, Hoskin M, Rother KI, Delahanty LM. "Diabetes Prevention Program Research Group. A High-Carbohydrate, High-Fiber, Low-Fat Diet Results in Weight Loss among Adults at High Risk of Type 2 Diabetes." J Nutr. 2017 Nov;147(11):2060-2066. doi: 10.3945/jn.117.252395. Epub 2017 Sep 27. (10) Huang RY, Huang CC, Hu FB, Chavarro JE. "Vegetarian Diets and Weight Reduction: a Meta-Analysis of Randomized Controlled Trials." J Gen Intern Med. 2016 Jan;31(1):109-116. doi: 10.1007/s11606-015-3390-7.