Is Sugar to Blame?
By Laura Freeman
On Halloween night, parents across the country turn into amateur endocrinologists. “If you keep eating all that candy,” they warn, eyeing their children’s mounds of sugary loot, “you’ll get diabetes!”
Excessive sugar intake can certainly alter a child’s behavior, but can a sweet tooth really bring on disease? “Sugar doesn’t cause diabetes, at least not directly,” says Fernando Ovalle, M.D., director of UAB’s Multidisciplinary Comprehensive Diabetes Clinic. But excessive calorie intake, whether from candy or other foods, can lead to obesity, Ovalle notes, and that “may help to trigger a susceptibility” to type 2 diabetes.
The timing of one symptom of type 1 diabetes could also help to explain why people intuit a link between sugar and the disease, Ovalle observes. “When some patients are developing diabetes, increased hunger and thirst may make them crave more sweet snacks and drinks,” he says, “but by then they are already sick.”
Both type 1 and type 2 diabetes are related to insulin, a hormone the body uses to convert sugar and other foods into energy. In type 1 diabetes, which affects 5 to 10 percent of patients, the body fails to produce insulin. Type 2 diabetes is brought on by insulin resistance, in which the body cannot use insulin properly.
Although sugar doesn’t cause diabetes, sensible consumption clearly helps patients manage the disease. Because sugar enters the bloodstream faster than many foods, overdosing on sweets can overwhelm a diabetic patient’s limited insulin supplies, says Ovalle. However, he notes, “other calories also have to be considered.” All foods contribute to the overall level of glucose in the blood, and strict attention to diet is one of the most important ways to combat the devastating health effects of diabetes. Poor blood glucose control has been linked to kidney and eye diseases; skin, circulation, and nerve problems; cardiovascular disorders; and even possibly a greater risk of cancer.
At UAB’s Multidisciplinary Comprehensive Diabetes Clinic, staff place strong emphasis on teaching patients what they can do to stay healthy, Ovalle says. Patients apply what they learn during morning nutrition classes by eating breakfast and lunch with a nutritionist. In the afternoons, they can meet with physicians from a broad range of specialties who treat the complications they are most likely to encounter.
Searching for Answers
So what does cause diabetes? That’s a complex question that researchers are still working hard to answer, says John Corbett, Ph.D., director of UAB’s Comprehensive Diabetes Center. “There seems to be a genetic component, but in identical twins, one may develop type 1 diabetes and the other doesn’t,” he says. And although there is a strong link between obesity and type 2 diabetes, “many obese people don’t develop it.”
The evidence points to a danger zone where susceptibility meets a trigger event. “Type 1 diabetes is an autoimmune process,” says Ovalle. “One hypothesis is that it could be triggered by a virus, a toxin, or something else in the environment. With type 2, lifestyle seems to be more involved; the factors that lead to obesity may be overwhelming the organs of susceptible people.”