PROTEIN Protein and its building blocks, called amino acids, are the substances that build the structures of our living body. They are composed of carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur. In our Mana Diet we recommend Chef Peter’s Veggie Fillet. If you prefer free-range, organic chicken, go ahead. BUT THERE ARE EVEN MORE PROTEINS THE BODY USES: Enzymes: Proteins that speed up the chemical reactions of the cells Hormones: Proteins that regulate metabolism in the cells Cellular respiration proteins: Other proteins that play a role in the exchanging of substances in and out of the cell through its outer membrane Immune system proteins: Other proteins that play a role in the immune system. Blood clotting proteins: Other proteins that enable the blood to clot Actin and myosin: Proteins that deal with muscle contraction and movement DNA: Some proteins even determine our DNA. As discussed earlier, plants make proteins and amino acids that have not yet formed into proteins. The role of nutrition is to link the foods we eat to our protein needs. It’s easy to track and regulate our protein and amino acid levels. For instance, although there are more than twenty amino acids listed on the USDA Food Table, (see www.nal.usda.gov/fnic/foodcomp/cgi), only nine are termed "essential." What that means is the body cannot synthesize these nine so they must be derived solely from the food we eat. Our body is able to synthesize the other twelve. To track what amino acids and proteins you need, examine The National Academies Dietary Reference Intakes Macronutrients Table (see www.nap.edu). By using this and the USDA tables you can manage your dietary intake. The tables above tell you a little about the "essentials" and the adverse effects of excessive consumption of amino acids and protiens. The table also tells you the recommended daily requirements. You should know that proteins are also essential for generating hormones. Some hormones are synthesized from fats (lipids), and some hormones are synthesized directly from amino acids called thyroxin. Most hormones are synthesized when amino acids bond together to form compounds called peptides. These peptides combine to form proteins that form hormones called peptide hormones. Hormones are synthesized by specific cells or organs and are secreted directly into the bloodstream. They produce an effect on other cells or organs, particularly influencing sexual development and growth, tissue and organ development, the texture of the skin and hair, and the excretion of water by the kidneys. Most hormones are produced in endocrine glands such as the pituitary, thyroid, parathyroid, pancreas, adrenal, ovaries, and testes. Some hormones are also produced in the cells of the nervous system, brain, kidneys, stomach, intestine, placenta, and liver. A good jumping-off point in your study of hormones (if you so desire) is the word "endocrine." Another type of protein that contributes significantly to the digestion of our foods, is the enzyme, which is more fully examined in the next chapter.