Hi R.---Ok, so don't get too excited about him not eating meat, nor about many of the suggestions made so far. He, and his body, are trying to tell you something. He instinctively knows that he doesn't need animal protein to survive. There is protein in every single type of food that God has put on this earth. There is LOTS of protein in plants. Contrary to popular advice, human protein needs are quite low and eating too much of it, which most Americans do, leads to chronic disease processes, like cancer, heart disease, type 2 diabetes and autoimmune disorders. Having said this, we do need to make sure he is eating an otherwise balanced diet. I'll get into that in a bit.
To back up a bit. I am taking wellness classes taught by a Naturopath who has her PhD in Nutrition. I have tons of resources to share on any health topic you would like to discuss. I'd also like to refer you to a couple of websites: www.pcrm.org (put dairy in the search box...lots of other websites within that one...look for the Vegetarian Starter Kit as well) and www.thechinastudy.com.
Here is a website that will help you determine how much protein is needed for optimal health: http://www.notmilk.com/protein.html. I know I have a chart with recommended amounts but can't find it right now. If you'd like it, send me a private message and I will be sure to get it to you...when I find it.
Protein needs have been incredibly overstated in the U.S. Several years ago, The World Health Organization established protein needs as being
2.5% of daily calories, and set the daily recommendation at 5% just to be safe. The average American is consuming many times that amount daily.
Protein is found not only in animal foods, but in grains, nuts and seeds, legumes and vegetables, meaning that it is unnecessary to consume animal foods to make sure that protein needs are met. In fact, protein deficiency is virtually unheard of except in places where people are starving and are not taking in enough calories daily.
When considering protein intake, it is important to remember that the body uses macronutrients in very specific ways. Protein is used for building, and is not an efficient source of fuel. Therefore, any protein that is not utilized by the body for building purposes must be excreted, and the organs of excretion for protein are the kidneys. Excess protein consumption places undue stress on the kidneys, and individuals do not generally know that they have induced kidney problems until there is serious loss of function.
Young children and athletes DO need additional protein for rapid growth and muscle building and repair. But these needs are met from consuming additional calories overall, from a balanced diet. With the balanced diet, enough protein is consumed on a daily basis.
Hope this helps. I do have lots of ideas on other health and diet topics as well, backed by articles and research. Feel free to pick my brain. D.