Sugar is a resident bogeyman in our dietary consciousness: It rots our teeth, makes us fat and causes diabetes. But it's also vital energy. And let's face it, it tastes good. The key to keeping it balanced is timing.
DURING THE DAY
"How your body uses sugar and what kind it uses depends on whether you're sedentary, active or exercising intensely," says James Stevens, R.D., who teaches sports nutrition at Metropolitan State College of Denver. Unless you're exercising, there's no need to consume added sugar, he says. When eaten, sugar is rapidly absorbed into the bloodstream, causing a surge in the hormone insulin, which clears it along with fat from the bloodstream to store in the tissue for future use. Go overboard with added sugar and eventually your body's insulin system stops working, and you end up with high blood sugar and eventually diabetes and other ills. The World Health Organization recommends limiting your sugar intake to 10 percent of your total daily calories. So if you eat 2,500 calories, 250 of them can be from added sugar.
"I recommend eating your daily sweet in the context of a balanced meal, like after lunch," says Stevens. Because you already have food in your system to offset the sugar load, you're less likely to eat a whole sleeve of Thin Mints than if you'd waited until midafternoon, when your blood sugar is low and you're vulnerable to intense sugar cravings. Plus, says Stevens, "It's the middle of the day, so you can adjust your activity level to burn it off."
ON THE MOVE
"One of the most common mistakes I see with athletes is that they overdo nutrition during events," says Stevens. "Your digestive system slows and your insulin levels are blunted during exercise, which means you can process only so much food and pull only so much glucose into your cells," he says. During exercise your body can process 30 to 60 grams of carbs per hour. For efforts lasting less than an hour, you don't need to replenish your energy stores with sports drinks, gels or bars. For longer rides, you should take in only as many carbs per hour as you can burn. Consume too much and you'll not only take in too many calories, says Stevens, but you'll also run into gastrointestinal issues.
Sugars in energy products come in different forms--glucose, fructose, sucrose and maltodextrin. For the best performance benefits, use products with a blend of sugars. In the past five years, three studies found that when trained athletes consumed drinks with mixed sugars during two-hour cycling tests, they were able to process, digest and absorb considerably more carbs per minute than when they drank single-sugar energy drinks. That's because each sugar has its own transport system in the gut, so when you tap out one, you may be able to squeeze more in using another.
"In the end, it comes down to what you like and what your body can tolerate," says Stevens. Genetically, we all have different abilities to digest and absorb various carbohydrates. Digestion becomes slower the faster you go, and all the carbs in the world will do you no good if you can't get them out of your gut and into your legs.
One way to cut back on sugar without giving up treats is to dupe your sweet tooth with artificial sweeteners. These chemicals are anywhere from 200 to 2,000 times sweeter than sugar, so they pack a lot of sweetness without the calories.
In theory, these products, such as Sweet'N Low, Splenda and NutraSweet, should help you keep your weight in check. In reality, artificial sweeteners have not been found to help people cut calories and lose weight. In fact, one recent study found the opposite to be true.
In an eight-year study of 1,550 soda drinkers ages 25 to 64, researchers found that those who drank diet soft drinks were at a greater risk for becoming overweight than those who sipped sugary sodas. In fact, for each can of diet soft drink consumed per day, a person's risk of obesity went up 41 percent. While this study may show only that people who drink lots of diet soda are trying (and ultimately failing) to control a weight problem, it also may say something about how the body responds to being tricked. Researchers speculate that offering your body something that tastes like sugar without delivering the calories it's expecting may actually sharpen your sweet craving and lead you to eat more later on. In the end, it's wise to use artificial sweeteners as much as you do the real deal: in moderation.
Credit: Bicycling Magazine