Plant-based diets and vegan diets have both made media headlines boasting their health benefits. They’ve been championed for their ability to decrease the risk of obesity, type 2 diabetes, heart disease, and other chronic conditions.
However, vegan diets sometimes make headlines for the opposite reasons.
This can be confusing, especially for those looking to transition to a plant-based diet to improve their health. The two diets have crucial differences, which explains why they can affect health in different ways.
Of course they have similarities, like the avoidance of animal products, but the role of processed foods can decide how they affect our health. It’s important to discuss the differences between a vegan and plant-based diet, especially when thinking about impacts on health.
What is a vegan diet?
Coined in 1944 by Donald Watson, the term vegan describes a diet that contains no animal products at all (meat, fish, dairy, or eggs). It was born from the term vegetarian, where the diet eliminates meat and fish, but includes eggs and dairy, sometimes referred to as ‘lacto-ovo vegetarian’ (1).
Being vegan goes beyond diet alone, referring to a lifestyle that avoids using, consuming, or exploiting animals wherever possible, for example, leather and wool aren’t worn, and products aren’t used if tested on animals. Many vegans choose this lifestyle based on animal ethics and environmental factors, and health considerations can also play a role.
A vegan diet can include varied amounts of processed foods depending on the individual’s dietary choices. Processed foods are modified food substances that have been altered from their natural state, they may only contain parts of a whole food along with chemical additives (2).
Technically, a vegan diet could be made up entirely of processed foods: vegan cakes and cookies, refined carbohydrates, fake meat, fake chicken, and even fake seafood. Whilst plant-based meat alternatives can produce better health outcomes than animal-derived meat (3), they’re not always considered healthy. They can contain excess salt, which is a risk factor for high blood pressure, and artificial additives and preservatives, and contribute to more weight gain than whole foods (4). Vegan cakes and cookies, along with refined carbohydrates like chips, are high in sugar and fat, and aren't good for human health. Sugar contains no nutritional value, can raise blood pressure, and increases our risk of type 2 diabetes and obesity (5).
It’s hard to know how much of these foods someone on a vegan diet is consuming. And as the market for vegan food grows, it’s easier to find these processed foods in supermarkets, and consume a vegan diet largely based on these.
What is a whole-food plant-based diet?
Those choosing to follow a whole-food plant-based diet are more motivated by the health reasons, compared to veganism which is a philosophy centered around animal ethics.
Animal welfare and the environment can still play a role in these decisions. Many who follow a whole-food plant-based diet may also consider themselves vegan, whereas others will still wear leather and use products tested on animals.
A plant-based diet isn't strictly vegetarian or vegan, but limits animal products as well as processed foods. You can be predominantly plant-based, where the overall focus is on whole plant-foods, with 10% coming from fish, meat, dairy, or eggs. Whole-foods have undergone little (if any) processing and are as close to their natural form as possible.
Example of whole-foods include:
- Whole grains
- Nuts and seeds
- Sometimes oils, such as extra-virgin olive oil
Whole-food plant-based diets tend to limit excess salt, sugar, and refined carbohydrates, which are commonly found in processed foods.
You may feel that this focuses on what you can’t eat, but a whole-food plant-based diet really focuses on the abundance of plant-foods available to you. There are so many fruits, vegetables, whole grains, legumes, nuts, seeds, herbs, and spices to experiment with and to find recipes for —it’s easily the most colorful diet out there.
Remember, a whole-food plant-based lifestyle, like the one we encourage at Mora, includes other lifestyle habits like stress management, sleep, social and community support, and physical activity, with the aim of optimizing an individual's health.
Why does the difference matter?
If you hear stories of people going vegan and feeling ill, it’s often a celebrity that the media jumps on for clickbait and increased readership. It can cause confusion around the healthfulness of these diets, and pushes the idea that someone needs animal foods to become well again.
This is far from the truth.
One thing that’s always missing from these anecdotes is exactly what people were eating. This is where it’s important to remember the difference between whole-food plant-based and vegan. If these diets consist of processed foods, high in sugar, salt, and fat, many of the factors that contribute to the development of chronic diseases still exist (6).
Like any diet, it’s important to consume enough of each food group to meet all your nutritional requirements, which is harder to do if half of your meal consists of vegan alternatives and processed foods. Processed foods are rarely a good choice, no matter the dietary pattern. Many vegans still consume a diet centered around whole-foods, but it’s important to remember that’s not always the case.
A whole-food plant-based diet, however, will always consist of minimally processed foods. This is the biggest difference between whole-food plant-based and vegan diets, and their effect on health.
If we take cardiovascular disease as an example, a study found that adhering to a healthy plant-based diet could reduce the risk of developing cardiovascular disease by up to 68%. However, the unhealthy plant-based diet increased risk by 34% (7).
So, whilst vegan diets can be healthy or unhealthy (depending on what the individual chooses) a whole-food plant-based diet is by default a healthy dietary pattern.
Why the term ‘vegan’ is used in science and nutrition
Despite the differences, the terms ‘vegetarian’, ‘vegan’, ‘plant-based’, and ‘whole-food plant-based’ still overlap.
In many large cohort studies (where researchers follow a large group of people, such as the Seventh-Day Adventists, to study the role of diet in disease) diet groups are split into vegan, vegetarian, pescatarian, semi-vegetarian and omnivore. This is an easier way to categorize dietary patterns and helps make clear the role of animal foods in the diet. Almost all of these studies point to vegetarian and vegan diets having the best health outcomes (8) (9) (10) (11).
Because vegans aren’t consuming animal products and often still center their diets around whole plant-foods, the data can also be used to look at plant-based diets and their health effects.
So, whilst Mora advocates for a whole-food plant-based lifestyle to prevent, heal, and reverse chronic disease, our research and blogs may use the terms vegan and vegetarian when we point to scientific evidence.
The plant-based diet index is another way for scientists to categorize vegan and plant-based diets in research studies. It gives positive marks to healthy plant foods and negative marks to unhealthy (processed) plant-foods and animal-derived foods. Diets are then split into healthful and unhealthful plant-based diets. This better resembles the amount of processed foods in the diet, as well as animal foods, and the role this plays in different health outcomes (6).
The bottom line
Vegan and whole-food plant-based diets share similarities such as the avoidance of animal-derived foods, and overlapping motivations of animal welfare, the environment, and human health.
However, they also have key differences, mainly the amount of processed foods included in the diet.
The term vegan describes what people don’t eat (animal products), compared to whole-food plant-based, which describes what people can eat (the clues in the name). This is where some confusion can come from regarding how healthy a vegan diet is, and why you may see media headlines that talk both negatively and positively about vegan diets.
A whole-food plant-based diet is healthy by default and reduces the risk of diabetes, obesity, cardiovascular disease, fatigue, specific cancer types, and more. A vegan diet can share these benefits and, on occasion, fall short depending on the inclusion of processed foods.
3. Crimarco A, Springfield S, Petlura C, Streaty T, Cunanan K, Lee J, et al. A randomized crossover trial on the effect of plant-based compared with animal-based meat on trimethylamine-N-oxide and cardiovascular disease risk factors in generally healthy adults: Study With Appetizing Plantfood—Meat Eating Alternative Trial (SWAP-MEAT). Am J Clin Nutr. 2020 Nov 11;112(5):1188–99.
4. Hall KD, Ayuketah A, Brychta R, Cai H, Cassimatis T, Chen KY, et al. Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake. Cell Metab. 2019 Jul;30(1):67-77.e3.
7. Kouvari M, Tsiampalis T, Chrysohoou C, Georgousopoulou E, Skoumas J, Mantzoros CS, et al. Quality of plant-based diets in relation to 10-year cardiovascular disease risk: the ATTICA cohort study. Eur J Nutr. 2022 Aug;61(5):2639–49.
8. Pettersen BJ, Anousheh R, Fan J, Jaceldo-Siegl K, Fraser GE. Vegetarian diets and blood pressure among white subjects: results from the Adventist Health Study-2 (AHS-2). Public Health Nutr. 2012 Oct;15(10):1909–16.
9. Watling CZ, Schmidt JA, Dunneram Y, Tong TYN, Kelly RK, Knuppel A, et al. Risk of cancer in regular and low meat-eaters, fish-eaters, and vegetarians: a prospective analysis of UK Biobank participants. BMC Med. 2022 Dec;20(1):73.