Both diets do not include animal products (if a “whole food plant based diet” includes animal products, it’s an 80/20 or 90/10 version – 80% plants, 20% animal product calculated by calories – OR – 80% whole food and 20% processed. Depends on the individual. Some may not call a diet that includes a fraction of animal products plant based though.)
The biggest dietary difference: a vegan diet does not have to be whole food, it can include processed food that does not include animal product. This is sometimes “vegan junk food”. An example of this is Oreos… most definitely not a whole food product.
A “whole food vegan” (doesn’t eat processed… no oreos) and a “whole food plant based” – the primary or perhaps only difference I guess would be animal welfare.
Veganism is not only diet. Veganism is a lifestyle and belief system, where you are also optimally avoiding animal products and products that are particularly harmful to animals – this would include clothing (down, wool, leather), palm oil, and so on.
Both “groups” are equally interested in sustainability (climate change and the like). And many plant-based dieters are also interested in animal welfare – so there is a lot of crossover.
I originally answered this question on Quora.
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