causally related to the evolutionary separation of humans from other primates. In modem times, few people in developed countries have to worry about either protein or caloric adequacy but there are at least one billion people on the planet who do not have adequate intakes of calories, or some of the nutrients that meat supplies in abundance such as vitamins B6 and B12, zinc, and iron in the biologically more available heme form. Meat is clearly a nutrient dense food beef, the most popularly consumed with meat in the United States having the highest concentration of vitamins and minerals(Fig. 1) is While meat a more nutrient dense food than most plant foods and consumed on regular basis by the majority of the population, there is concern raised by many observational studies that high intake of red and/or processed meat intake is associated with chronic diseases such obesity type 2 diabetes, cardiovascular disease, and a variety of cancers. As a result of such observational studies, many governmental and non-governmental health agencies have recommended restriction of World processed meat intake (Superior Health Council, Cancer Research Fund/American Research, Institute for Cancer 2012) The two referenced organizations recommend maximum week of red meat at 100g/d and g/wk, respectively; both recommend minimal intake of processed red meat products based on increased risk of colon cancer. This paper will address the limitations studies on which those recommendations are based, address one existing research gaps, and try to describe the degree of certainty one can have concerning these putative relationships