Let's say you eat a simple carbohydrate, such as a piece of fruit or a candy bar. Eaten alone, it would enter your bloodstream in the form of glucose and raise your insulin level almost instantly. Proteins, such as lean cuts of meat, poultry, fish, eggs, nuts, and low-fat dairy products, take much longer to digest and are broken down into their smallest components, amino acids. Amino acids, for the most part, do not stimulate insulin secretion. Protein also requires the body to put forth a greater amount of effort for a longer period of time to digest it, which once again slows down the digestive process.
When a carbohydrate is eaten in combination with a protein, it becomes a new source of energy on a molecular level. So when a simple carbohydrate is eaten in combination with a lean protein source, such as a piece of cheese or a slice of turkey, that combination of foods goes through a very different digestive process than if either is eaten alone. When you combine carbohydrates with proteins, less glucose enters the bloodstream, and it is released over a longer duration of time. This lowers your insulin level so your body can burn the carbohydrates as fuel as opposed to storing them as fit.
Another important factor to consider is those endless cravings for sugar or carbohydrates. Eating a little protein with each meal will reduce your cravings for such foods. Let me explain. When you eat sugar or a carbohydrate alone, it raises(spikes) your insulin levels, but what goes up must come down. So when your insulin level drops, it creates a craving for more sugar or carbohydrates for immediate energy and to get "high" again, because now you are feeling tired and lethargic. Sounds like an addiction, right? It's something to think about. However, when you eat a little protein with each meal, which forces the secretion of glucagon(the hormone that stimulates insulin secretion), your insulin level balances out so your body doesn't go through the insulin roller-coaster ride. The result is that you have a sustained, well-balanced energy level throughout the day instead of that tired, lethargic feeling you may usually experience around midafternoon.
The premise behind a higher-protein diet is that it's not the protein or fat in our daily diet that is causing the obesity epidemic, it is the excess of high glycemic carbohydrates and carbohydrates eaten alone and in excess that create and store fat. In other words, lean sources protein and good fats will not make you fat they are eaten in the proper proportion. Fat does not induce a secretion of insulin. Do you remember the low-fat craze that swept through our country not so long ago? Every major food manufacturer jumped on the bandwagon and made low-fat versions of almost every food product. What happened? We got fatter, not thinner! We ended up eating more of those low fat foods because they didn't fill us up due to the reduced fat content and the fact that they were high in sugar and carbohydrates. Consider this: an entire chicken breast has approximately 300 calories; a small Snickers bar has approximate 275 calories. The chicken breast does not require the secretion of insulin, but the Snickers bar does. As a consequence, when eating the Snickers bar there is a greater chance your body will store these calories in your fat cells; eating the chicken breast will not.
