I still feel it depends on your bodytype. I have tried the vegetarian way and I gained weight and felt sluggish.
So I could say grains, fruit etc made me gain weight.
If I eat low/no carbs I loose weight and have more energy.
Several years ago I read that about 1/3 of the people do better on high protein and low carbs.
Of course I agree that you need to eat the right "healthy" food.