What Is a Plant-based Diet?With a plant-based diet, also sometimes called a whole-foods diet, you follow these basic principles:
- Vegetables, fruits, whole grains, legumes, nuts, seeds, and healthy oils make up the majority of what you eat.
- Meat, fish, poultry, and other animal products are allowed, but they are typically eaten infrequently and in small portions.
- Processed foods, and refined grains and sugars are avoided.
- Food quality matters; therefore, locally sourced, organic, non-genetically-modified (non-GMO) foods are preferred.
Popular documentaries such as “Forks Over Knives,” and best-selling books such as Michael Pollan’s In Defense of Food: An Eater’s Manifesto, shined light onto plant-based diets. One of Pollan’s most well-known food mantras is: “Eat food. Not too much. Mostly plants.” In “Forks Over Knives,” researchers explored the potential large-scale health effects if people change their diets from animal-based to plant-based.
Someone who adheres to a plant-based diet typically eats:
- Fruits: Bananas, berries, citrus fruits, peaches, pears, pineapple, etc.
- Healthy fats: Avocados, coconut oil, olives, olive oil, etc.
- Legumes: Black beans, chickpeas, lentils, peas, etc.
- Non-sugary condiments: Mustard, nutritional yeast, salsa, soy sauce, vinegars, etc.
- Nuts, nut butters, and seeds: Almonds, cashews, macadamia nuts, natural peanut butter, pumpkin seeds, sunflower seeds, tahini, etc.
- Plant-based proteins: Legume protein (e.g., black beans), plant-based protein powders that do not contain added sugar or artificial ingredients, tofu, tempeh, etc.
- Spices, herbs, and seasonings: Basil, black pepper, mint, rosemary, salt, thyme, turmeric, etc.
- Unsweetened plant-based milks: Nut milks such as almond milk or cashew, coconut milk, etc.
- Vegetables: Asparagus, butternut squash, broccoli, cauliflower, carrots, kale, lettuces, peppers, potatoes, tomatoes, yams, etc.
- Whole grains: Barley, brown rice, farro, quinoa, rolled oats, etc.
- Some alcoholic beverages in moderation (2–3 servings per week); typically those that don’t contain added sugar and aren’t mixed with other sweetened beverages
- Still water
- Unsweetened sparkling water
- Unsweetened teas
- Free-range, organic chicken
- Organic dairy products from pasture-raised animals
- Pasture-raised eggs
- Pastured-raised or grass-fed beef or pork
- Raw honey
- Wild-caught, sustainable seafood
What Is Vegetarianism?In its most basic definition, vegetarianism is defined as avoiding animal products. However, there are different forms of vegetarianism, each of which has a distinctive set of guidelines or, in some cases, strict rules.
- Flexitarianism: Flexitarians are sometimes called “casual vegetarians.” They generally follow some form of vegetarianism, but occasionally eat meat and fish.
- Lacto-ovo vegetarianism: This is the most common type of vegetarian diet. Lacto-ovo vegetarians eat both dairy products and eggs, but no meat, poultry, and fish.
- Lacto vegetarianism: This means dairy products are eaten, but eggs, meat, poultry, and fish are not.
- Ovo vegetarianism: These vegetarians eat eggs, but not dairy products.
- Pescatarianism: Pescatarians eat mostly plants, but will also include fish in their diets.
- Veganism: Vegans avoid all animal-based foods, including honey.
- Raw veganism: Raw vegans eat mainly raw fruits, vegetables, legumes, sprouts, and nuts.
Generally speaking, the motivation for adopting a vegetarian diet may be prompted by religious, cultural, or animal-rights concerns. That’s not to say there aren’t health benefits associated with vegetarian diets—there definitely can be.
Pros of Plant-Based Diets and VegetarianismScientific evidence supports eating more plants, which both plant-based diets and vegetarianism zero in on. Research shows that there can be a number of potential health and environmental benefits. Here are some.
Less Cognitive DeclineSome studies have shown that the plant compounds and antioxidants found in plant-based and vegetarian diets can help slow or prevent impaired memory, language, thinking, and judgment—either due to age-related cognitive decline or Alzheimer’s disease. A nine-study review in Frontiers in Aging Neuroscience found that eating more fruits and vegetables resulted in a 13 percent reduction in the risk of developing cognitive impairment or dementia.
Lower Diabetes RiskA group of more than 200,000 people who ate healthy plant-based diets had a 34 percent lower risk of developing diabetes than those who followed unhealthy, non-plant-based diets, according to a study published in PLOS Medicine, a medical journal published by the Public Library of Science.
Another study, done by four researchers and published in Diabetes Care, showed a connection between vegans and lacto-ovo vegetarians and a 50 percent reduction in type 2 diabetes risk versus non-vegetarians. Additionally, for people with diabetes, plant-based diets may improve blood sugar control.
One man, whose story was featured on the Forks Over Knives website, said he lost 50 pounds, reversed his diabetes, and stopped taking all medications after following a plant-based diet for three months.
Lower Cancer RiskOne study, which was partially funded by the American Institute for Cancer Research, found that vegetarians had a nearly 10 percent lower risk of developing any cancer than non-vegetarians.
More specifically, a large study of more than 77,000 people found that vegetarians had a 22 percent lower risk of developing colorectal cancer than non-vegetarians. And pescatarians had a 43 percent reduced risk compared to non-vegetarians.
Lower Heart Disease RiskA study published by the Journal of the American College of Cardiology demonstrated that people who followed plant-based diets rich in vegetables, fruits, whole-grains, legumes, and nuts had a significantly lower risk of developing heart disease than those following non–plant-based diets. However, unhealthy plant-based diets that included refined grains, and fruit juices and other sugary drinks were linked to a slight increased risk of heart disease.
Smaller Carbon FootprintGreenhouse gas emissions, water consumption, and land used for factory farming all contribute to global warming and environmental degradation. Those who follow plant-based and vegetarian diets may have smaller environmental footprints because the production, processing, and distribution of meat requires large amounts of pesticides, fertilizer, fuel, feed, and water while also releasing greenhouse gases, manure, and toxic chemicals into the air and water. The Environmental Working Group found that red meat, such as beef and lamb, is responsible for 10 to 40 times as many greenhouse gas emissions as common vegetables and grains.
That said, rice is known to have a substantial carbon footprint due to the amount of methane it produces. Additionally, some findings show that people are more likely to throw away perishable fruits and vegetables than meat and fish, thus contributing to greater food waste. However, other research reveals that people who regularly buy local produce tend to limit the frequency of wasting vegetables by up to 90 percent.
Preventing Weight GainA study published in the American Journal of Clinical Nutrition determined that people who ate about half a pound of meat a day gained more weight over the course of five years compared to those who ate less animal protein.
However, vegetarians can sabotage weight-loss goals if they fill their plates with unhealthy processed, packaged foods that are high in calories, as well as unhealthy fats, sugars, and refined grains.
Cons of Plant-Based Diets and VegetarianismAlthough research supports eating more plants, there can be potential downsides to adopting a plant-based vs. vegetarian diet. Consider the following examples.
Change Can Be ToughIf an eating style is not already in place, adaptation can take some time. Those trying to adjust might find that they have to put more thought and time into meal planning and prepping, especially at first. They might also have cravings for certain foods that were previously consumed during their previous dietary patterns and eating habits.
Not All Food Is Created EqualAlthough processed food technically refers to any food that has been altered in some way during preparation—meaning chopped, bagged, and frozen spinach is technically processed food—not all processed food is as nutrient-rich as the spinach found in the grocer’s freezer section.
The unhealthy, processed culprits are foods such as chips fried in unhealthy fats and doused in sodium, drinks filled with added sugars, and packaged desserts laden with artificial sweeteners—all of which can come with vegetarian or rich-with-plants marketing labels. It’s important to read all the ingredients and choose wisely.
Additionally, unless a plant is labeled “non-GMO and organic,” it may be genetically modified and doused in synthetic pesticides.
Plant Foods Can Be ExpensiveOrganic plant foods often come with higher price tags than their non-organic counterparts. Why? It can be more difficult and expensive to grow organic foods. Most small farms and community-supported agriculture programs aren’t subsidized by the federal government and controlling pests without chemicals can be an ongoing, labor-intensive challenge (e.g., physically removing insects from plants and relocating them vs. spraying); therefore, they must charge more in order to stay operational.
Supplementation May Be RequiredVegans and some vegetarians can struggle to get enough vitamin B12, which is only found naturally in animal products. Vitamin B12 helps generate red blood cells and prevent anemia. Mushrooms, spirulina, some fortified plant-based milks, and fortified nutritional yeast contain B12, but eating enough of these foods to get an ample amount can be tough for some, and therefore supplementation may be required. Calcium, iron, omega-3 fatty acids, and vitamin D supplementation may be necessary, but can be found in a balanced vegetarian diet.
In SumAlthough they resemble each other, plant-based diets and vegetarianism differ enough to make it worthwhile to understand the subtleties. Most important, if you are considering changing your dietary habits, be sure to talk with your healthcare practitioner to develop a plan that’s right for you and your health needs.
*Editor’s Note: The information in this article is intended for your educational use only; it does not necessarily reflect the opinions of the Chopra Center's Mind-Body Medical Group; and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health providers with any questions you may have regarding a medical condition and before undertaking any diet, supplement, fitness, or other health programs