CHAPTER 5
Pick a Perfect Protein Package
PART 1
Replenishing Protein
EnergizedProtein is a dietary energy source, providing calories like its nutritional counterparts, carbohydrate and fat. Together, these three macronutrients provide nearly all the calories we consume. Though the calorie counts in carbohydrates and proteins are essentially matched at 4 calories per gram (fat has 9 calories/gram), the calories from protein burn slowly, making it an especially long-lasting source of energy. READ MORE
The slow burn of protein is due in part to its complex structure. Every type of protein is constructed of a long sequence of amino acids; you might think of protein as a chain and amino acids as the links. Protein varieties number in the hundreds of thousands, each with a sequence that is unique in the number, type, and order of amino acids in its chain.
Re-Energized
Protein is the material of life, and once spent in support of your body’s growth and functioning, it needs to be replaced. The body can synthesize (create) some amino acids on its own and begin linking together new protein chains. But without every link available and in its proper sequential position, the completed protein will never materialize.
Of approximately 20 amino acids, nine must come from the diet. Since it is essential for these nine amino acids to be sourced from food, they are called the “essential” amino acids — even though all 20 are truly vital. And because the body does not store amino acids or even complete proteins in any readily available form, the supply needs to be replenished daily through the foods you consume. LESS
PART 2
“High Quality” Protein Food Sources
Animal meats are often equated with protein, but they are not the only source — and not necessarily the best source, either. READ MORE
Red meat, poultry, and fish are typically referred to as “complete” or “high quality” proteins because the amino acid structures within them very closely match the forms in which they are used by the human body. Because the animal-based proteins are so similar to the completed proteins in our own bodies, we can put these foods to use quite efficiently. However, quality and efficiency do not necessarily translate to good health. One often-noted detriment is that a serving of meat may deliver not only the desired protein but undesirable, unhealthy fats. LESS
PART 3
Challenge Your Assumptions
It is the entire protein package, then, that is important when deciding on which foods should supply your daily allowance. There are two perspectives on the packaging, too: (1) How proteins are packaged in foods along with other nutrients; and (2) how amino acids are packaged within proteins. READ MORE
A host of plant-based foods, including beans, nuts, and whole grains, are well packaged with vitamins, minerals, and fiber. Meats, on the other hand, naturally occur with saturated fats. Unless you choose lean meats, the animal fat should be cut away before cooking. There is compelling evidence today that plant-based proteins may ultimately be much healthier for you than animal-based proteins.
Plant-based proteins are characterized as “incomplete” or “low quality” only because the amino acids in them don’t come all neatly linked together in complete protein chains — but so long as the body is provided with every essential amino-acid link, it can build the protein chains on its own. Soy is a singular exception since it is both plant-based and complete in its offering of all essential amino acids.
Seeking Balance
While the experts continue to debate the value and vagaries of various foods, the balanced recommendation is to seek a broad variety of protein sources. Currently, the reigning wisdom is to seek between 10 and 35 percent of your daily calories from protein sources, with an emphasis on plant proteins such as beans, lentils, soy and nuts. LESS