Introduction

“An ounce of prevention is worth a pound of cure” referred to the benefits of preventing fires, not disease. But Ben Franklin’s aphorism also applies to people at risk for type 2 diabetes. Some 26 million Americans already have type 2 diabetes, incurring healthcare bills totaling $250 billion a year. Millions more are at risk for developing the disease. If current trends continue, one in three Americans will have diabetes by 2050.
The major cause of the type 2 diabetes epidemic is obesity. Excess body fat not only swells the waistline but also alters the blood, filling it with inflammation-causing chemicals that make various tissues more resistant to insulin, the hormone that directs cells to absorb glucose from the bloodstream to use as an energy source.
“The body compensates for insulin resistance by telling beta cells in the pancreas to make more insulin,” says Jeffrey E. Pessin, Ph.D., professor of medicine (endocrinology) and of molecular pharmacology, the Judy R. and Alfred A. Rosenberg Professorial Chair in Diabetes Research and director of the Diabetes Research Center at Einstein.  “But this works only for so long. Over time, beta cells have an increasingly hard time secreting insulin, and they eventually begin to fail.” Insulin’s absence allows sugar levels in the blood to rise, setting the stage for serious health complications such as heart disease, hypertension, kidney failure, foot amputations and blindness.

Could type 2 diabetes and its complications be prevented? To find out, Einstein and 26 other sites nationwide collaborated on a landmark clinical trial—the Diabetes Prevention Program (DPP)—that began in 1995. The DPP studied whether a lifestyle intervention (modest weight loss and exercise) or treatment with metformin (an oral diabetes drug that suppresses glucose production in the liver) could prevent or delay the onset of type 2 diabetes in people at high risk for the disease.The results of the DPP, published in the New England Journal of Medicine in 2002, showed clearly that these measures could help prevent type 2 diabetes and that lifestyle changes were especially effective.

For overweight adults with prediabetes (blood glucose levels higher than normal but not high enough to warrant a diabetes diagnosis), their incidence of diabetes was reduced by 58 percent with lifestyle changes and by 31 percent with metformin, compared with those who received a placebo. People 60 and over especially benefited from lifestyle intervention, which reduced their diabetes risk by a remarkable 71 percent. And lifestyle changes worked equally well in men and women and across all major ethnic groups.
Allen M. Spiegel, M.D., then director of the National Institute of Diabetes and Digestive and Kidney Diseases (the trial’s primary sponsor) and now the Marilyn and Stanley M. Katz Dean at Einstein, called the DPP findings “a major step toward the goal of containing and ultimately reversing the epidemic of type 2 diabetes in this country” and noted that “every year a person can live free of diabetes means an added year of life free of the pain, disability and medical costs incurred by this disease.”
The DPP showed that overweight or obese people can avoid or delay developing type 2 diabetes simply by losing weight—ideally through regular physical activity and a low-fat, low-calorie diet. Millions of people urgently need to adopt those measures, as the following statistics show:

• More than one-third of American adults (35 percent) were classified as obese in 2011–2012 (as noted in an October 2013 report from the National Center for Health Statistics). This translates to more than 78 million people at high risk for developing type 2 diabetes.
• In New York City, 58 percent of adults and nearly 40 percent of children are overweight or obese. As a result, one in three adult New Yorkers now has type 2 diabetes or prediabetes.
• The obesity epidemic is especially acute in the Bronx, with one of the highest obesity incidences of any county in the United States. Nearly 70 percent of Bronx adults—about 630,000 people—are overweight or obese.
• $4 billion is spent annually in New York City on healthcare costs related to obesity.