What Is a Plant-Based Diet? A Complete Beginner’s Guide

Dropping the phrase “plant-based diet” is hip when you're talking nutrition these days. Why? Lauren Manaker, RD, who is based in Charleston, South Carolina, suspects it’s because of increased awareness of the health and environmental benefits that are associated with eating this way. Some of that could be the result of documentaries that throw shade at eating meat and other animal products, such as Game Changers (2018), What the Health (2017), Cowspiracy (2014), and Forks Over Knives (2011).

But what does “plant-based diet” mean, anyway? Is it the same thing as being vegetarian or vegan? Or does this diet just mean you make an effort to pack more veggies into your meals?

Technically, all of the above interpretations are correct. “Some people use the term ‘plant-based diet’ as a synonym for the vegan diet,” says Summer Yule, RD, a nutritionist in Hartford, Connecticut. “Others may use the term in a broader way that includes all vegetarian diets, and I’ve also seen people use ‘plant-based’ to mean diets that are composed mostly, but not entirely, of plant foods.”

The idea is to make plant-based foods the central part of your meals. “A plant-based diet emphasizes foods like fruits, vegetables, and beans, and limits foods like meats, dairy, and eggs,” Manaker says. From there, more restrictions could be put in place depending on how strict you want to be. “It may completely eliminate foods from animals or just limit intake, depending on the individual’s interpretation,” Manaker says.

That means meat and seafood don’t necessarily need to be off-limits — you might just decide to cut down on how frequently you eat those items, according to Harvard Health Publishing.

Think of “plant-based” as a broad category, with other more specific diets falling under its umbrella. For example, the Mediterranean diet is a version of a plant-based diet because even though it incorporates fish and poultry, the emphasis is on plant-based foods, Manaker says.

Plant-based diets include:

• Vegetarian
• Vegan
• Pesco vegetarian
• Semivegetarian or flexitarian
• Ovo vegetarian
• Lacto vegetarian
• Lacto-ovo vegetarian
• Raw vegan

Whole30, a popular diet and lifestyle plan, doesn’t usually qualify. “The Whole30 diet traditionally is heavier on animal proteins, though it is possible to follow this diet in a plant-based way,” Manaker says.

In the United States, having a poor-quality diet is the biggest predictor of early death, according to an article published in the May 2017 Journal of Geriatric Cardiology. A classic American diet that’s high in saturated and trans fats, sodium, and processed meat puts you at a disadvantage when it comes to health and longevity, while a diet that promotes whole foods and plant-based ingredients appears to have the opposite effect.

Indeed, most people who adopt this way of eating do it for the potential health benefits. “There have been many cardiac benefits linked to eating this way, like reduced cholesterol,” Manaker says. “Some studies suggest that eating a plant-based diet may improve fertility parameters, and it also may reduce your risk of developing [type 2] diabetes.” A well-planned plant-based diet can be safe for everyone, including babies, children, and people who are pregnant or nursing, the Academy of Nutrition and Dietetics noted in its 2016 position paper.

As the following research suggests, a plant-based diet may help reduce the likelihood that you’ll need medication, lower your risk of obesity and high blood pressure, and maybe even help prevent or manage type 2 diabetes and heart disease. Here’s a closer look at possible plant-based diet benefits.

A Reduced Risk for Type 2 Diabetes

In a review published in July 2018 in JAMA Internal Medicine, researchers found that following a plant-based diet (one that included foods like fruits, veggies, legumes, nuts, and whole grains) was associated with a lower risk of type 2 diabetes. The nine studies involved about 307,100 participants, and were adjusted for factors such as smoking status and exercise frequency that otherwise could have affected the results. Researchers therefore deduced that the lower risk was due to participants’ diet choices.

The reason for this lower risk of type 2 diabetes may be improved function of beta cells, which help produce insulin (the hormone that keeps blood sugar levels stable). Past research has noted that as type 2 diabetes progresses, beta cell function declines — and this can cause dangerous fluctuations in blood sugar levels. But a randomized trial found that after just 16 weeks following a plant-based diet, participants had better beta cell function and insulin sensitivity compared with the control group — not to mention improved body mass indexes (BMIs) and less belly fat. Manaker agrees that a plant-based diet can help you manage your weight, and may even lead to weight loss if you follow it in a healthy way. “Most people [who transition from a typical American diet] also start to feel like they have more energy,” she adds.

A Healthier Weight and Blood Sugar Level in People With Diabetes

In another study, which was published in September 2019 in Translational Psychology, researchers concluded that this diet is beneficial for boosting metabolism, managing weight, and reducing inflammation, especially among people with obesity and those with type 1 and type 2 diabetes.

Another study found that a plant-based diet may play a role in preventing and treating type 2 diabetes, and the authors cite research that suggests this diet may help reduce the risk of other chronic illnesses, including cancer. One review suggested that a plant-based diet has a positive effect on emotional and physical well-being, quality of life, and general health for people living with type 2 diabetes, while also improving physical markers of the condition in this population.

A Reduced Risk of Heart Disease

One study linked diets rich in healthy plant foods (such as nuts, whole grains, fruits, veggies, and oils) with a significantly lower risk of heart disease.

Another found that following a diet rich in plant foods and lower in animal foods was associated with a 16 percent lower risk of cardiovascular disease and 31 to 32 percent lower risk of death from cardiovascular disease.

There are several factors in play here, including the fact that plant-based diets can decrease cholesterol levels and lower inflammation, according to a case report.

A Reduced Risk of Cancer

Research from the United Kingdom looked at about 475,000 adults who were cancer free at baseline. The participants were categorized as regular meat eaters, low meat eaters, fish eaters, and vegetarians and followed up to check their incidence of cancer 11.4 years later. The low meat eaters, fish eaters, and vegetarians had a lower risk of colorectal, breast, and prostate cancers when compared with regular meat eaters. The researchers suspect a low BMI could also be a contributing factor to the lower cancer risk.

Another study focused on breast cancer specifically and found that individuals who most closely followed a plant-based diet had 67 percent lower risk of breast cancer than those who followed it the least.

One note: If you’re not ready to give up on animal proteins just yet, don’t worry. Another study found that, while adding plant-based proteins to your diet can help lower your risk of cancer and cardiovascular disease, there was no increased risk associated with animal proteins. So while it’s not necessary to completely eliminate meats and dairy from your diet, you can still lower your risk of certain diseases by making an effort to include more plant proteins. To set yourself up for success, Manaker suggests making a shopping list heavy on produce, beans, and plant-based proteins to make sure you have plenty of options to reach for when you get hungry.

For Black Americans, who are disproportionately affected by many chronic diseases, a plant-based diet may reduce the risk of heart disease and potentially cancer, according to one review.

A Healthier Brain

A plant-based diet could be helpful for both your body and your mind. While research is mixed, one study involving more than 3,000 adults found sticking with a plant-based diet was linked with better cognitive function, including long-term memory and executive function, though future research should explore the mechanisms behind why this happens.

A Longer Life

Some research links a diet containing higher levels of plant protein with a lower rate of early death from all causes; one review of studies (involving more than 715,000 participants) found that participants whose diets contained the most plant-based protein had a 6 percent lower risk of premature death than individuals who consumed less protein overall. One study of 135,000 individuals found a link between increased intake of fruits, vegetables, and legumes and a lower risk of all-cause early death, with participants reaping maximum health benefits at three to four servings per day — an amount that anyone following a plant-based diet is likely to meet.

Although there are plenty of reasons you may want to adopt a plant-based diet, from a lower risk for chronic diseases to a reduced carbon footprint, weight loss may be another outcome you’re after.

Good news: A plant-based diet can help in this way, too.

According to a review on vegan and vegetarian diets, these eating styles may help prevent overweight and obesity in a healthier, more sustainable way than other eating approaches. The same review cites several studies associating plant-based diets with weight loss. For example, of 12 studies analyzed in one meta-analysis, participants randomized to follow a plant-based diet lost about 4.5 pounds more than individuals who followed a different, non-plant-based diet.

As the Physicians Committee for Responsible Medicine notes, plant-based diets may aid weight loss because they call for whole foods, which are rich in filling fiber. What’s more, limiting or avoiding higher-fat foods including meat may support your weight goals, because 1 gram (g) of fat is the equivalent of 9 calories, whereas 1 g of carbohydrate has only 4 calories. Cutting calories may support weight loss.

Simply sticking with plant-based foods likely isn’t going to cut it — you’ll need to pay attention to the quality of the foods you’re consuming, because there are plenty of unhealthy foods that qualify as plant-based, such as potato chips and french fries. Unhealthy plant-based foods will increase your risk of weight gain and health conditions such as heart disease.

Another thing you should be aware of: When you first switch to a plant-based diet, you may notice an uptick in bowel movements, diarrhea, or constipation. That’s because many plant-based foods are loaded with fiber, Manaker says, and fiber normalizes bowel movements, according to the Mayo Clinic. Consider gradually incorporating plant-based foods in your diet to give your body time to adjust, and be sure to drink plenty of fluids while you're making the switch to eating more plants and afterward.

For the most part, eating a plant-based diet will check the boxes of all the major nutrients. “A well-planned plant-based diet can be nutritionally adequate and particularly rich in fiber, vitamin A, vitamin C, and potassium because of all the fruits and vegetables that are typically eaten,” Yule says.

That said, if you decide to take the plant-based diet to the next level and swear off all animal products, you may need to keep an eye on your levels of vitamin B12 and choline. “Vitamin B12 is found primarily in animal sources, and the two best sources of choline are egg yolks and liver,” Manaker says. “If a person is avoiding animal products, they may not be taking in enough of these nutrients.”

What to Eat and Drink

• Vegetables (including kale, spinach, Swiss chard, collard greens, sweet potatoes, asparagus, bell peppers, and broccoli)
• Fruits (such as avocado, strawberries, blueberries, watermelon, apples, grapes, bananas, grapefruit, and oranges)
• Whole grains (such as quinoa, farro, brown rice, whole-wheat bread, and whole-wheat pasta)
• Nuts (walnuts, almonds, macadamia nuts, and cashews all count)
• Seeds (such as flaxseed, chia seeds, and hemp seeds)
• Beans
• Lentils
• Coffee
• Tea (including green, lavender, chamomile, or ginger)

What to Limit (or Avoid Entirely, Depending on the Plan You Choose)

• Dairy (including milk and cheese)
• Meat and poultry (like chicken, beef, and pork)
• Processed animal meats, such as sausages and hot dogs
• All animal products (including eggs, dairy, and meat if you’re following a vegan diet)
• Refined grains (such as “white” foods, like white pasta, rice, and bread)
• Sweets (like cookies, brownies, and cake)
• Sweetened beverages, such as soda, and fruit juice
• Potatoes and french fries
• Honey (if vegan)

Day 1

Breakfast Tofu scramble

Lunch Cauliflower rice bowl with black beans, corn, avocado, and salsa

Dinner Veggie-topped pizza

Snack Zucchini chips

Day 2

Breakfast Oatmeal-based breakfast muffins

Lunch Tomato basil soup with oyster crackers

Dinner Veggie stir-fry with tofu

Snack Hummus wrap

Day 3

Breakfast Homemade oatmeal bars

Lunch Greek salad with a slice of whole-grain pita bread

Dinner Kale and tofu curry

Snack Cashew yogurt with berries and a scoop of peanut butter

Day 4

Breakfast Breakfast burrito with eggs, peppers, and salsa

Lunch Veggie burger and a side salad

Dinner Cauliflower “steak” with roasted sweet potato fries

Snack Veggies with hummus

Day 5

Breakfast Dairy-free yogurt with berries and granola

Lunch Tomato sandwich with pesto and a drizzle of olive oil

Dinner Whole-wheat pasta with roasted tomatoes

Snack Roasted chickpeas

Day 6

Breakfast Chia seed pudding with fresh berries and a spoonful of almond butter

Lunch Avocado toast

Dinner Vegan mushroom enchiladas

Snack Handful of almonds

Day 7

Breakfast Oatmeal with almond milk

Lunch Quinoa bowl with roasted carrots and sweet potatoes

Dinner Vegetarian chili topped with slices of avocado

Snack Whole-wheat toast topped with peanut butter

Feeling overwhelmed, because plant-based eating is a complete 180 from your current diet? Don’t overthink it. Here, Yule offers five tips on making the transition.

1. Think Outside of the Produce Aisle

Stock up on grains, canned beans, and canned or frozen fruits and veggies so you don’t have to shop every few days.

2. Swap Meat for High-Protein Legumes

Tofu, tempeh, black beans, chickpeas, pinto beans, and dried peas are some of your many options. You can also use plant-based protein powder and certain other high protein foods, such as seitan.

3. When Eating Out, Ask the Waiter for Suggestions

Sometimes a server will help you piece together a meal with sides and appetizers if there isn't a plant-based main course on the menu.

4. Choose Budget-Friendly Options

Keep grocery costs down by buying in-season produce and sticking to simple plant-based foods such as grains, beans, and frozen and canned foods.

5. Keep Nutrition Basics in Mind

Limit the sugar, fat, and refined grains you cook with at home. These ingredients can quickly make a home-cooked plant-based meal unhealthy.

Best Book About Plant-Based Diets

The Plant-Based Diet Revolution: 28 Days to a Healthier You by Alan Desmond and Bob Andrews

This 2021 title is a cross between an explainer that argues eating plant-based is the best for overall well-being and a step-by-step guide to adopting this lifestyle in a month’s time. The science comes from author Alan Desmond, MD, and the 80 recipes to help you transition into this new way of eating come courtesy of chef Bob Andrews.

Best Plant-Based Diet Blog

Oh She Glows

Angela Liddon, the founder of the blog Oh She Glows, is not new to plant-based eating. She’s been creating plant-based recipes — and posting them on her blog — since 2008. That means she has a database of more than 500 recipes, including many that are also gluten free and allergy free.

Best App for Sticking With a Plant-Based Diet

Oh She Glows ($1.99)

Oh She Glows is also our pick for the best app for sticking with a plant-based diet. For many, the hardest part about eating this way is coming up with things to eat for every meal of the day. That’s why this app is such a lifesaver. You can search for recipes by title, ingredient, meal, or dish type. Each recipe featured in the app also includes detailed nutritional information. Finally, you can favorite the recipes you try and love so you can come back to them again and again.

Best Website for Plant-Based Diet Info

Forks Over Knives: The Beginner’s Guide to a Whole-Food, Plant-Based Diet

This site (from the same folks behind the Forks Over Knives film) is a wonderful primer on everything you need and want to know about transitioning to a plant-based diet. It breaks down the cost of groceries, offers a recipe database, and answers common questions, such as how to continue eating plant-based while traveling and how to make sure you’re getting the nutrients you need.

Best Podcast for Those Interested in a Plant-Based Diet

PLANTSTRONG

This podcast from Rip Esselstyn is focused on promoting plant-based living. Each episode features a well-informed guest — usually someone in the health realm or a plant-based advocate — to further that goal. The show has a backlog of more than 150 episodes, so there’s plenty of content to keep you learning.

The plant-based diet is a category of diets that have this in common: “All plant-based diets limit animal-derived foods in favor of plants,” Yule says. Instead of a diet centered on meat and dairy, the starring roles are played by vegetables, fruits, and whole grains. It’s a fresh, flavorful approach to eating and has been shown to have significant health benefits, including weight loss and disease prevention.

Additional reporting by Laura McArdle.