Diet Protein Deficiencies
There are some ways you can become protein deficient, but it’s pretty hard.
One way to become protein deficient is to get almost all of your calories from alcohol and/or sugar. Sugar contains no protein! Hard liquor contains virtually no protein (beer contains very small amounts.) So if you are an alcoholic sugar junkie, you may be in danger of protein deficiency.
Another possible source of deficiency is that infants may be fed foods which they cannot digest.
Because of the sufficiency, or overabundance, of plant protein, animal products (milk, cheese, and eggs as well as meat, fish, and poultry) are completely unnecessary for adequate protein nutrition. Breast milk, incidentally, which has provided human infants with adequate protein for hundreds of thousands of years, provides 6% of calories as protein – far less than that of whole cow’s milk, which contains 22% of calories as protein.