Whether you're going full vegan or just stocking up on kale, eating more plants certainly has its benefits.

By Toby Amidor
Credit: casanisaphoto/Getty Images

Plant-based eating is becoming one of the most popular eating styles, for both health and environmental benefits. A 2017 Nielson home study found that 39 percent of Americans were actively trying to eat more plant-based—and, indeed, a 2018 study by Nielsen commissioned by the Plant Based Foods Association found that sales of plant-based foods increased by a whopping 20 percent in just one year.

But what does "plant-based" mean, exactly?

Truthfully, it can be kind of confusing since the term is not clearly defined.

"In the past, the definition of 'plant-based' (as used by nutrition researchers and organizations) has meant a diet based primarily on plants; however, the definition has emerged to mean different things to different people," says Sharon Palmer, R.D.N., The Plant-Powered Dietitian. More recently, people have been using the term to mean a 100-percent plant-based vegan diet, she notes.

On the other hand, registered dietitian Amy Myrdal Miller, M.S., R.D.N., F.A.N.D., founder and president of Farmer's Daughter Consulting in Carmichael, CA, defines plant-based more broadly as, "following the Dietary Guidelines and the MyPlate pattern where the majority of foods come from plants (like fruits, vegetables, grains, nuts, plant-based oils)." (See: What's the Difference Between a  Plant-Based and Vegan Diet?)

It's worth noting that, while plant-based diets come with tons of benefits, following a vegetarian or vegan diet doesn't automatically mean you're eating healthy. That's because most of the health benefits described below don't simply come from reducing animal products—they come from increasing consumption of healthy, whole foods.

"Whether you're eating a plant-based diet with plants and a smaller amount of animals or decided to go vegan, eating more plants in your diet has numerous benefits," says Myrdal Miller. Here, some of the benefits you can score whether you decided to go full veg or just opt to eat more plants. (See: Plant-Based Diet Rules You Should Be Following)

1. Lower risk of heart disease.

Extensive research shows that people who consume the most fruits and vegetables have the lowest risk of cardiovascular disease, says Myrdal Miller.

One study by the Icahn School of Medicine at New York's Mt. Sinai Hospital looked at more than 15,000 people with no known issues of heart disease who followed one of five dietary patterns including convenience (fast food and fried food), plant-based (fruits, vegetables, beans, fish), sweets (desserts, candy, sugary breakfast cereals), southern (fried foods, organ meats, processed meats, sugar-sweetened beverages), and salad and alcohol (salad dressings, vegetable salads, alcohol). The study followed these individuals over four years and found that those who stuck to a plant-based diet had a 42-percent decreased risk of heart failure compared to those eating fewer plant foods.

Again, it's not just about limiting animal foods; food choices matter. (It's kind of like clean vs. dirty keto.) Another study published in 2018 in the Journal of the American College of Cardiology examined the food choices of male and female health professionals and created a plant-based diet index to gauge the healthiness of their diet. Healthy plant foods (such as whole grains, fruits, vegetables, oils, nuts, and legumes) were given positive scores, while less-healthy plant foods (such as sugar-sweetened beverages, refined grains, fries, and sweets, and animal foods) received a reverse score. The data revealed that a more positive score was associated with a lower risk in coronary heart disease.

The study shows that it's not about having any type of plant-based food (like French fries) but rather the quality of the plant-based foods you select that's most important. Your plant-based diet should still consist of well-balanced plants like whole grains, fruits, vegetables, oils, nuts, and legumes, that are prepared and cooked in a healthful manner. (Try these plant-based diet recipes for every meal of the day.)

2. Lower risk of type 2 diabetes.

Eating a plant-filled diet can also help prevent type 2 diabetes. A 2017 article published in the Journal of Geriatric Cardiology looked at the potential benefits of a plant-based diet on type 2 diabetes based on numerous studies. One of them examined the prevalence of type 2 diabetes in relation to different eating patterns and found that it was less common in diets with reduced animal products.

Based on this and numerous other observational studies examined in this review, scientists concluded that eating a plant-based diet may help improve insulin resistance, promote a healthy body weight, increase fiber and phytonutrients, allow for better food and microbiome interactions and decrease saturated fat. (Related: Can the Keto Diet Help with Type 2 Diabetes?)

3. Decreased risk of obesity.

Clinical and observational research shows that adopting a plant-based diet may help reduce risk of becoming overweight and obese—and even help promote weight loss according to a 2017 review article published in the Journal of Geriatric Cardiology.

Interestingly enough, even moderate adherence to a vegetarian diet could prevent overweight and obesity in middle age, according to 2018 research by the European Association for the Study of Obesity—showing that you don't have to go 100 percent vegan and can still lose weight including lean sources of animal protein in your diet.

"Research on populations who follow vegetarian eating patterns shows they have lower rates of overweight and obesity," agrees Myrdal Miller. (Pssst you should also check out the Mediterranean Diet, which has a ton of health benefits.)

4. Decreased risk of cancer.

Eating a plant-based diet (along with other healthy behaviors) may actually help decrease your risk of cancer.

A 2013 study published in Cancer Epidemiology, Biomarkers & Prevention followed about 30K post-menopausal women for seven years and found that women maintaining normal body weight, limiting alcohol, and eating mostly-plant based was linked to a 62-percent reduction of breast cancer compared to women who did not follow these three guidelines.

A report by the American Institute for Cancer Research backs that up, saying that a healthy diet and lifestyle behaviors could prevent 40 percent of cancer cases. That's why the American Institute of Cancer Research (AICR) recommendations eating a plant-based diet, primarily consisting of fruit, grains, beans, nuts, and seeds, with some animal foods for cancer prevention. This type of diet helps you get a variety of plant foods' cancer-protective nutrients such as fiber, vitamins, minerals, and phytochemicals, according to the AICR. The AICR recommends filling your plate with 2/3 (or more) of plant foods and 1/3 (or less) of fish, poultry or meat, and dairy.

5. Environmental benefits.

True, eating a plant-based diet can have some health benefits for your body—but it can have some larger implications for the Earth as well. (Related: I Tried Creating Zero Waste for One Week to See How Hard Being Sustainable Really Is)

"It takes fewer inputs (water, fossil fuels) to produce these plant foods, and they do not produce outputs like manure or methane that can be harmful to the environment," says Palmer. "In today's agriculture, so much of our crop production goes to feeding animals, when we could just eat crops directly rather than feeding them to animals and eating the animals." That's one of the reasons Palmer says that the environmental impact is higher in animal foods compared to plant foods. (Here: Small Tweaks You Can Make to Effortlessly Help the Environment)

"Study after study has shown plant-based eaters have a lower environmental footprint," she says. "This is true of carbon emissions, as well as issues like water footprint and land usage (the amount of land it takes to grow food)."

Before you demonize all animal food production, know that plant and animal agriculture are actually pretty integrated.

"Livestock upcycle much of the leftovers from crop processing, essentially taking the waste products generated from producing the plant-based foods we like to eat and upgrading them into other food products," says Sara Place, Ph.D., senior director for Sustainable Beef Production Research. (Related: Biodynamic Farming Is the Next-Level Organic Movement)

For example, in California, juice production from oranges leaves the rest of the fruit (pulp and peel) after processing, and this citrus pulp is often then fed to cattle resulting in the production of beef and milk. Almond hulls (the portion of the nut surrounding the meat that humans eat) are also fed to dairy cattle, converting what could be waste into nutritious food. Suddenly that choice between almond milk, cow's milk, and orange juice don't seem so different.