Puffy bags under the eyes, especially in the morning, may indicate a lack of protein. Water retention, swollen ankles, puffy face and hands, can also result from a protein deficiency. Nails are made of protein, not calcium as some think. A protein deficiency can be marked by split, extremely thin nails. Nails that fail to grow quickly lack protein.
The structure of the hair follicle is protein. There are eight amino acids that the body does not produce and therefore must come from complete protein foods such as milk, cheese, eggs, fish, fowl and meat. Protein powders are an excellent source of complete proteins.
L-Cysteine and L-Methionine are the amino acids that form "keratin", which is the protein structure of hair. Studies have shown that supplementing with L-cysteine may prevent hair from falling out, as well as increase the diameter of the hair shaft. These amino acids have been found to increase hair growth by as much as 100 percent. MSM (organic sulphur) is also valuable for beautiful hair and nails. I personally add it to my daily protein drink!