What Is a Plant-Based Diet?

One thing much of the country seems to agree on is eating more plants. More than half of Americans (63 percent, regardless of political affiliation, according to a 2021 study by the Yale Program on Climate Change Communication) are actively trying to eat less red meat. In the United States, plant-based products grew into an $8 billion industry in 2022, with a growth rate of 7 percent since the year before.

This phrase comes up more and more as we see the effects of climate change — extreme heat, more powerful storms and the like. You may have questions, so here’s a look at what this means.

What is a plant-based diet?

The exact definition of a plant-based diet can vary, and the term is often used interchangeably with vegan. Yet they are not the same thing.

Any food labeled vegan will be plant-based — but the reverse is not always true.

Generally speaking, a plant-based diet consists largely of vegetables, fruit, beans, legumes, grains and nuts, with little or no meat, dairy or fish. People who follow plant-based diets do so for reasons of health, animal welfare concerns, or environmental consciousness.

Veganism is a moral philosophy based on animal rights that abstains from all animal products, including meat, dairy, eggs, honey and products containing leather, silk or wool, or that have been tested on animals.

This distinction matters, because while many people are not interested in giving up animal products entirely, any reduction in our consumption of those foods will help the planet.

Are plant-based and vegan diets better for you?

Not necessarily. Vegan, plant-based and omnivorous diets (and pescatarian and vegetarian diets for that matter) can all be made up of whole, fresh ingredients (called whole-food diets, which are good for you) or highly processed ones (which are not). The more processed foods you include in your diet, the worse it is for your health, whether your chicken nuggets are made up of real or vegan chicken.

Because the term “plant-based” is not regulated by the Food and Drug Administration, it’s become a widely used marketing tool. You’ll find it on products of dubious healthfulness, like ultraprocessed instant noodles, chips and energy bars.

However, eating a plant-based diet based on whole foods has been shown to have myriad health benefits, including reducing your diabetes risk, improving your gut microbiome and generally helping you live longer.

Do I have to give up animal products entirely to follow a plant-based diet?

Most experts (Harvard Medical School, for example) define plant-based as a diet primarily made up of plants, with small amounts of meat, fish and dairy consumed very occasionally — anywhere from a few times a week to a few times per month.

Limiting your consumption of meat and dairy has been shown to have significant positive effects for planetary health and can also be beneficial for your health — as long as you replace meat and dairy with whole and minimally processed foods like vegetables, fruits, legumes, nuts and grains — and not diet sodas and vegan doughnuts.

So no, you don’t necessarily need to go cold turkey on the turkey.

Are plant-based and vegan diets better for the environment?

Yes, and the body of evidence supporting this is growing. Yet another major study has recently been published, showing that eating a plant-based diet is significantly better for the environment than eating a meat-based diet.

The research, conducted by Oxford University, found that people who follow a meat-free diet are responsible for 75 percent less in greenhouse gas emissions than those who eat meat every day, and that following a low-meat, vegetarian or pescatarian diet is proportionally less detrimental to land, water and biodiversity than a meat-heavy diet.

Other studies have shown that the production of meat and dairy products — particularly from cows — emits as much carbon each year as all cars, trucks, airplanes and ships combined. (This is true whether that meat was factory farmed or raised organically.)

The more plant-based you can make your diet, the more planet-healing it will be.

Of course the kinds of drastic, swift changes necessary for real progress will require ambitious action in government and corporate policy. But the cultural shift already underway is a necessary step in this direction.

What about cheese?

In terms of greenhouse gas emissions, many cheeses, such as Cheddar and mozzarella, may be even worse offenders than pork, chicken and fish. So a pescatarian or a flexitarian who eats small amounts of chicken or bacon every once in a while, but skips those cheeses, can have more of a more positive impact on the planet than a vegetarian who consumes loads of cheese and dairy every day.

Are plant-based meats healthier than conventional meat?

It depends on what’s in them, and brands vary wildly. While, in general, plant-based meats tend to be lower in saturated fats and can be higher in fiber, they can also be higher in sodium and calories. Read the labels carefully before you buy.

How do I start cooking more plant-based meals?