A friend of mine posted a free nutrition class from https://www.coursera.org/courses . I have enrolled in the class. After the first week i am so pleasantly surprised at what i have learned and what is being taught. Our son's body knows how little protein a body needs, less than one gram per kg of weight or 0.46 grams per pound. I learned in the class the RDA recommend the same amount or even less. Many highly developed nations such as the US eat almost 3 times the amount needed. The excess protein is sweated out in the form of ammonia, but excess ammonia lowers one's body pH and can create health issues, especially is one isn't physically active enough to sweat it out.
The class also recommends a great food tracking tool giving the limits of what one should eat and what foods contain empty calories. The site link is https://www.supertracker.usda.gov/default.aspx . My only compliant is the list food in this program is very limited. There are other food diary programs that have a larger list and where foods can be manually added, but does not show the limits or empty calories, such as http://www.fitday.com/ .
Having kept a food diary for our son, i wasn't surprised to see how much protein is in plant based foods and how little animal products are needed to meet one's needs. The class example was for a 170 pound adult male. He ate one medium size egg and 2.5 ounces of chicken (~ the size of a child's size fast food burger) to meet his protein needs. The remaining needed protein was obtained from plant based foods.
I will keep you posted on the class as it progresses.