Mike Nevin was always a big guy. Big but fit. Back when the 39-year-old architect was snapping footballs at the University of Idaho, he was able to comfortably carry 305 pounds—much of it muscle—on his 6'1" frame. In 2002, 15 years after being the biggest big man on campus, Nevin was still expanding, though by exactly how much was a mystery, since he never felt the need to weigh in. "My energy levels were good. I never felt tired," recalls Nevin, who by then was newly married and living in Boise. "I was still pretty active, skiing, playing softball, golf, flag football. I could physically do what I had to do without having a heart attack."
As the pounds piled on, Nevin adjusted his life by increments. He had his ski boots reshaped to fit his expanded calves. He traded up in pants size. His was a strategy of "gain and compensate," and it helped him build a wall of denial as thick as his thighs. Then, in 2002, one part of Nevin's body grew at a rate that alarmed even him: his lymph nodes. They were enlarged, and he had no choice but to see a doctor. And a scale.
"It turned out the lymph thing was no big deal, but one of my doctors was worried I might be a candidate for diabetes," says Nevin. "He recommended I visit an endocrinologist." For a guy used to posting huge numbers in the weight room during his prime—500 pounds on the bench, 650 in the squat—Nevin was blown away by the stats in the specialist's report. Weight: 345 pounds. Body-mass index: 45. Triglycerides: 300. Glucose: 145. By every measure, Nevin was twice the man he should be. "The doctor scribbled down the words 'obese' and 'insulin resistant,' " he says. "Then he told me if I didn't do something fast, my next step could be full-fledged diabetes."
What Happens in Your Body When You Eat that Grande Deluxe Burrito
For a syndrome with deadly consequences, insulin resistance is saddled with a pretty wimpy name. Which might help explain why so few people have heard of it, let alone given it the respect it deserves. Basically, insulin resistance short-circuits the body's system for burning and storing fuel—even in people who aren't Nevin heavy. In fact, being just 10 to 20 pounds overweight can land you in the physiological frying pan. "It's possible to be lean and insulin resistant, just as it's possible to be overweight and not be," says Robert H. Eckel, M.D., director of the endocrinology lab at the University of Colorado health-sciences center. "But the general rule is, the heavier you get, the more resistant you become."
To comprehend the level of mischief-making caused by insulin resistance, it first helps to understand how a healthy body converts food into energy for cells. A rice-and-bean burrito that goes down your gullet is digested in the intestine, where much of it turns into glucose, or blood sugar, the simple energy source that powers cells. But because glucose can't penetrate cell walls on its own, the party doesn't get started until insulin, a hormone secreted by the pancreas, arrives on the scene. Insulin flows quickly throughout the body, attaches at receptors lining the surface of certain cells, gives the secret handshake, and escorts glucose through the door.
Now, if that burrito you snarfed happened to be, say, a grande deluxe with cheese and you washed it down with 20 ounces of soda, then you've just inhaled more potential energy than your body can possibly use at the moment. No problem. Ever-thrifty insulin steers the surplus glucose to the liver, where it's shelved as glycogen, and to fat cells, where it's rejiggered into triglycerides for safekeeping until, oh, the next famine rolls around. "When insulin drops low enough, we can metabolize our fat," says Dr. Eckel. "Most of us with normal fat stores could live for months without eating."
In a healthy body, glucose and insulin coexist in dynamic equilibrium, sort of like the NASDAQ and the Dow. Glucose goes up, insulin trails right behind. As glucose drops, the pancreas ratchets back insulin output. It's a brilliantly engineered system, particularly if you happen to belong to a nomadic tribe of hunter-gatherers. For cubicle dwellers who forage at the Gas 'n' Go and hunt at Burger World's drive-thru window, it can be murder.
For reasons not entirely understood, cells in the liver, as well as in muscle and fat tissue, can begin to ignore insulin when it comes knocking. This indifference—or loss of sensitivity—is the cornerstone of insulin resistance and the trigger for a sequence of major health problems to follow. (See, fellas, sensitivity can be a good thing.) With access denied, glucose begins backing up in the blood. The always-alert pancreas reads the growing imbalance and responds by cranking out extra insulin. Eventually, insulin succeeds in breaking down the doors to resistant cells and starts stashing glucose, but it might require three times the normal amount of the hormone. Not to mention excessive wear and tear on the pancreas.
As long as insulin gains the upper hand and the pancreas can meet the extra demands placed on it, the diagnosis is confined to insulin resistance. Should the pancreas start to sputter and glucose skyrocket, then all hell breaks loose. Sugar begins spilling into the urine and barging into random cells, unescorted and unwanted. Diagnosis: type 2 diabetes. Most people who have insulin resistance will progress to diabetes, unless they take charge of their health. Untreated, type 2 diabetes can lead to blindness, kidney failure, impotence, and amputation.
Continue reading the second part of this article!
Technorati tags: Diabetes, Type 2, Prevention, Glucose, Insulin, Diet.
Blogalaxia tags: Diabetes, Type 2, Prevention, Glucose, Insulin, Diet.