When it comes to dealing with the rapidly inflating diabetes epidemic, U.S. public health experts face a long, tough road ahead. Diabetes rates are expected to soar: As many as 1 in 3 adults will develop the chronic, life-threatening disease by 2050 compared to 1 in 10 with type 1 or type 2 diabetes today, according to estimates released Friday by the federal Centers for Disease Control and Prevention. And drugs to treat obesity, a major cause of type 2 diabetes, are in the dumpster: While the obesity drug Meridia (sibutramine) was withdrawn from the market earlier this month due to its link to heart attacks and strokes (not that it was particular effective), lorcaserin, an experimental weight-loss pill, will probably never be sold. It was rejected a few days ago by the Food and Drug Administration due to still-unanswered questions about its effects on diabetics and concerns over an animal study showing high rates of cancer in rats that were given the drug.
While Arena Pharmaceuticals, maker of lorcaserin, vows to continue pursuing approval, Jack Lief, its chief executive, acknowledged in a Monday conference call with reporters that obesity drugs don't work very well in diabetics. The FDA is currently reviewing applications for two other experimental obesity drugs, but if the past is any indication, they, too, may only produce modest weight loss along with health risks that may not be known until the drugs are prescribed to many folks for years. (Meridia was on the market for 13 years before the full extent of its heart risks became known.)
So what's wrong with simply allowing diabetes rates to rise and treating high-blood sugar levels with one of the drugs that lower blood sugar? While the medications do help prevent soaring blood sugar levels, which can wreak damage on the heart, nervous system and kidneys, the landmark ACCORD study showed that these drugs—which include metformin, Actos, and Avandia—have never been proven to reduce rates of diabetes complications like nerve damage, heart attacks and vision loss. "In...ACCORD participants with established type 2 diabetes and additional risk factors for cardiovascular disease, intensive lowering of blood glucose reduced some markers of eye, nerve and kidney disease compared with standard glucose control, but the groups did not differ in the rate of progression to kidney failure, nerve disease, and major vision loss," lead author Faramarz Ismail-Beigi of Case Western Reserve University, Cleveland, wrote in a June statement released with the study. In the months since, the FDA severely restricted sales of Avandia due to data suggesting it posed a greater risk of heart problems.
The best way to prevent diabetes—and reverse it in those who are diagnosed—is a healthy lifestyle. But even here, researchers find room for debate. What exactly should you eat to keep your blood sugar levels fairly stable throughout the day, avoiding sudden spikes and plunges that increase appetite and overeating? At last month's European Association for the Study of Diabetes conference in Stockholm, nutrition experts debated the merits of various diets for diabetes control. Duke University nutritionist Eric Westman touted the benefits of the Atkins diet. In his research, he found that the superlow-carb Atkins diet (which allows just 20 grams of carbohydrates per day, less than what's in a banana) reduced the level of A1C hemoglobin, the key blood sugar marker, far more than could traditional diets recommended for diabetics, which contain about 100 grams of daily carbohydrates. However, Westman is coauthor of the latest Atkins book and takes honoraria from Atkins Nutritionals, and his views aren't shared by all.
A recent study found that compared with a more-traditional diet, an Atkins-style diet rich in beef, cheese, pork, and other saturated fats increases the risk of death while a vegetarian version based on tofu and nuts lowers it. Based on this finding, some experts contend that a South Beach-style diet, which emphasizes lean protein like fish and turkey breast, few starches, and lots of vegetables, is the best diet for diabetes control. Then again, the American Diabetes Association declines to endorse any of the best-selling diet books—the ADA says there's no good long-term data comparing the various diets in terms of their ability to reverse diabetes. "Our position is that diets need to be individualized," says Stephanie Dunbar, ADA director of nutrition and medical affairs. "People come into diabetes with very different dietary patterns and cultural differences" that need to be taken into account when customizing a diet plan. But most experts agree, she adds, that any diet plan should include a lot of non-starchy vegetables.
In general, losing excess weight, whatever diet plan gets you there, is vital for better control of diabetes. Exercise is also critical. Studies suggest that 30 minutes of daily activity (walking, biking, swimming) helps lower blood sugar levels, promotes good heart health, and accelerates weight loss for those already cutting calories. "Everyone's showing that exercise is important when it comes to diabetes," says Dunbar.