I tried being a strict 80% raw/Vegan for about 2 years and my health failed me miserably. I was to skinny, cold all of the time, no sex drive at 20 years old, and I ended up in the hospital with my doctors telling me I needed a lung transplant.
Since i've started eating meat again I feel infinitely better. I am healthy weight, I have more energy, I have more strength, I am healthier than I have ever been.
You cant deny evidence like that. Some people just do better with some meat :)