This is a complex subject and there are many motivations behind why you would would to supplement your nutrient rich diet, or not. But check your biases at the door, because the answers here are not as clear cut at you might like them to be.
You may know that you do not need to be vegan or vegetarian to eat Nutrient Rich successfully. But when you change the question from plant vs animal, to one of what are the most nutrient rich foods, you'll end up eating a predominantly plant based diet for the rest of your life especially when you understand these two points...
Brock was inspired by the fact that most green vegetables are about 50% protein. Matter of fact, all protein comes from plants or as the Nutrient Rich logo illustrates from photosynthesis. According to Dr. Fuhrman you only need an extra 7 grams of protein per day to add an extra pound of muscle, assuming you are training! Otherwise protein does not add muscle on its own.
Banana Sam, this guy is rich in more than just potassium, but in an array of nutrients. Yeah this guy is hi GI (Glycemic Index) and proud of it! That's why you eat bananas for quick energy from health promoting sugar. He's also struttin' his stuff because he also knows he's a mainstay in millions of smoothies every day.
The Karote Kid is kickin' because he's getting way more than carotene's in those carrots and all the other vegetables, fruits, beans, raw nuts and seeds and whole grains he's eating. He's getting all the nutrients he needs to stay health, perform and succeed.
She's Berry Beautiful because she like her brothers is antioxidant rich... really rich! She's vibrant healthy and attractive because all those berries have disease proofed herself. She's sweet too ;-)
When you start eating nutrient rich, amazing things happen to your health. You give your body the true nutrients it needs to function and perform well. You feel really good and energetic. You’ll want to eat this way and your body will start craving the good stuff.