I'm going to talk to you about the hormone whose name you've heard many times: insulin. Some of the content of this chapter is fairly complex, but I think you ought to read it carefully. Because for many of you, the answers to your battie with the bulge and concerns about long-term health issues are here.
Almost everyone knows that insulin is given to people with a certain kind of diabetes, to help control their bloodsugar levels when their own supplies become depleted or insufficient. Insulin is one of the most powerful and efficient substances that the body uses to control the use, distribution and storage of energy. At its most basic, insulin is the control hormone for glucose, a basic form of sugar. So listen up.
Your body is art energy machine, never resting, alwnys metnbolicaHy active—-and it powers its operations mainly through the use of glucose in the blood, which is why glucose is interchangeably called blood sugar. The body must maintain a certain level of glucose in the blood at all times. So when there is no cabohydrate food source to make glucose, the liver will actually convert protein to glucose. Remarkably, even on a prolonged, total fast, a healthy body can maintain its glucose level within n rather narrow normal range. As a general rule, of course, the body obtains its principal supply of fuel from food.
What Happens to a Meal
You sit down at the table and consume a three-course dinner. Somewhere between chewing and excreting, your body absorbs certain substances from your food, mostly across the surface of your small intestine. From the carbohydrate you eat, your body will absorb sugars, all of which are, or quickly and easily become, glucose. From fat, it absorbs glycerol and fatty adds, and from protein, it absorbs amino acids, the building blocks of all cells.
Obviously, if you eat a lot of carbohydrate, you'll end up with a lot of glucose in your blood. Sounds good, doesn't it? All that energy coursing through your system. Eat sugar, starches and fruits and you're going to get those blood-sugar levels up fast, aren't you? If you love candy bars, perhaps you're saying, "That's great=-the more I eat, the more energy I'll have:'
Alas, a bad mistake. You see, the human body evolved and primitive humans thrived as hunter-gatherers who subsisted ptimadly on fish, fruit, whole and seeds and nuts. Candy bars were few and far between. The hmnan body is used to dealing with unrefined foods m they occur in Nature. Consequently, your body's capacity to deal with an excess of processed foods is pretty poor, which is why our twentytint-century way of eating so often gets us into trouble.
If you don't understand this yet, let's look at what insulin and the other energy-controlling hormones do when you eat.
As Your Blood Sugar Rises
Consuming carbohydrates impacts your blood-sugar levels. The amount of carbs—and the typo—will determine bow your blood sugar responds. For example, a food full of refined sugar and white flour, such as a jelly doughnut, will raise blood sugar much more dramaticaHy than does a salad.
To be useful to your body, blood sugar has to be transported to your cells. Think of insulin as the barge that romsports glucose from your blood to your cells. Once it reaches the cells, three things can happen to that glucose: It can be mobilized for immediate energy; it can be converted into glycogen for later use as a source of energy; or it can be stored as fat. Let's delve in a little deeper. Insulin is manufactured in a part of your pancreas called the Islets of Langerhans. As the sugar level in your blood goes up, the pancreas releases insulin to move the sugar out of the blood. It then transports the blood sugar to your body's cells for their energy needs. But as we previously mentioned, when these needs are met the liver converts excess glucose into glycogen, which is stored in the liver and muscles, where it is readily available for energy use. Once all the glycogen storage areas are filled, the body has to do something with excess glucose. And here is the big revelation: The liver converts the remaining glucose to fat, which becomes the "storage tanks" of fat on your belly, thighs, buttocks and elsewhere. That's why insulin is called "the fat-producing hormone;'
Since fat is much more eflieient—-and has more capacity to store energy—glucose, we can store a lot more fat in our bodies than glucose. That, my friends, results in obesity. And by the way, the main chemieal constituent of all this fat (the fat you're reading this book to get rid oO is uiglyceride, the very same triglyeeride that, in your blood, can be a risk factor for heart disease and stroke.
Insulin is a pretty efficient worker. If it were not, your cells could not get enough glucose, their basic fuel, and blood-glucose levels would rise while the cells searched for other fuels-first for protein in your muscles and orgnns, add then for fat in your fat strum. That's why people with poorly controlled, insulin-deficient diabetes can lose weight when no insulin is present. And that's why a person on a low-calorie diet may lose lean body mass. (This shouldn't happen on Atkins, where sufficient calories and protein are consumed to meet the body's energy needs.)
On the other hand, excessive carbohydrate intake results in high amounts of blood sugar and may, in turn, overstimulate insulin production. When this happens, it causes a drop in blood sugar, robbing the body of energy for the cells. The resuit of the process is destabilized blood-sugar levels, quite possibly causing fatigue, brain fog, shakiness and headaches.
The body attempts to adjust by liberating counterregulatory hormones—-such as adrenaline—to raise the glucose level, but another stiff dose of insulin can overpower the effect of those hormones. Fortunately for most of us, this glucose balancing act takes place automatically and our blood sugar stays in a fairly narrow, normal range.
But for some, the bodily insult of massive insulin release to deal with massive bio