A plant based diet will seldom give the nutrients you need unless you are very mindful of it. The problems usually start with b12 that is almost only found in meat and fish. Tryptophan is another nutrient that is also abundant in meat but not so much in vegetables and fruit.
I'm not against vegetarianism. I just think that it should be done responsibly. Eat two eggs every day at least to avoid the pitfalls. And make sure to get omega 3. There are good vegetarian sources of this essential fatty acid. But meat and fish is still the major food source.
Thanks for your reply, I would recommend you check out the links I provided in my post regarding your views on any supposing pitfalls regarding a plant-based diet. I doubt the World Health Organization would support a plant-based diet if it wasn't healthy, which they do. I appreciate your views though.