Vegetarians should turn to fruitarianism.
The most important thing is fruits should be eaten raw all the time. Raw is king.  Many vegetables need cooking. The reason many vegetables need cooking is they are not edible raw. Vegetables are not true human food because they need preparation. Before cooking was invented, humans did not eat vegetables.
Here is a note from a forum post by my teacher. Barefoot Herbalist MH writes this clear and simple:
“Most vegetables today are all modified from poisonous plants, tomatoes, potatoes, etc. I can’t think of one vegetable in the modern garden that is a Native Plant, this is why vegetables are not true human foods. They grow too fast and their minerals are organic, but too large and enter the blood stream and deposit. fruits/berries do not deposit, do not grow fast, they get their minerals from their roots that take all winter to absorb.”
http://curezone.com/forums/fm.asp?i=712886#i