Very happy to see this great set of resources from the Mayo Clinic – Vegetarian Diet: How to Get the Best Nutrition – which begins:
Adopting a healthy vegetarian diet isn’t as simple as scraping meat off your plate and eating what’s left. You need to take extra steps to ensure you’re meeting your daily nutritional needs.
A healthy vegetarian diet consists primarily of plant-based foods, such as fruits, vegetables, whole grains, legumes, nuts and seeds. Because the emphasis is on nonmeat food sources, a vegetarian diet generally contains less fat and cholesterol, and typically includes more fiber.
No matter what your age or situation, a well-planned vegetarian diet can meet your nutritional needs.
They even created a vegetarian version of the food pyramid:
Nice to see this coming from mainstream health sources, not just the PCRM.