Obesity and diabetes are America’s newest epidemics, and Mainers are among those suffering the most.
Obesity is now so prevalent in America that the number of children who are overweight or obese has doubled in the last 20 years. Among teenagers, the number has tripled. In Maine, one in four high school students and one in every three kindergartners are overweight. A study by Sarah Anderson at Ohio State University and Dr. Robert Whitaker at Temple University published in April in the journal Archives of Pediatrics & Adolescent Medicine showed one in five 4-year-olds in America is obese.
Inactivity and diets long on calories and short on nutrition have more than a few public health officials fearing that, because of obesity, today’s children may be the first generation in America who won’t live as long as their parents or grandparents. For both children and adults, every pound of excess weight makes them more susceptible to heart disease, cancer and type 2 diabetes.
Like obesity, diabetes is also rampant in the United States. The incidence of diabetes has doubled in the last 10 years. More than 23 million Americans have the disease, with about 1.6 million new cases diagnosed each year. One highly educated guess by Dr. Gerald Bernstein, an endocrinologist and past president of the American Diabetes Association, predicts the number of Americans with diabetes will reach 50 million within the next 25 years, with associated annual treatment costs of $1 trillion.
Particularly alarming is the growing prevalence of type 2 diabetes. Type 2 was primarily a disease of adults until it began emerging in overweight grade-school children. Today it accounts for 90 percent of all diabetes.
Ongoing research at The Jackson Laboratory by Ed Leiter and his collaborators shows the role of genetics in diabetes is a complex puzzle complicated by the impact of genetics on obesity (www.jax.org/diabetes). The interactions of many genes are associated with the clinical reality that, while 7 percent of those who are obese develop type 2 diabetes, about 90 percent of those with type 2 diabetes are obese. The linkage between obesity and type 2 diabetes is so inextricable that some researchers have coined the term “diabesity” to reflect the simultaneous emergence of both conditions.
Research at the laboratory conducted by Dave Serreze and his collaborators is also showing that susceptibility to autoimmune diseases such as type 1 diabetes may involve gene variations that once protected primitive societies against infectious diseases that today no longer pose a threat. When those diseases were in play, these genes contributed to a potent immune response. Now, with disease pressures reduced or removed due to better hygiene and modern medicine, these genes may have an autoimmune dark side. In other words, when the immune system isn’t challenged by enough pathogens, it may attack the body’s own cells and tissues, increasing susceptibility to type 1 diabetes.
Susceptibility and resistance to human disease vary widely among individuals. Understanding this genetic variation is essential to a future of personalized medicine in which prevention, diagnosis and treatment are tailored to each individual’s unique genetic makeup. The Jackson Laboratory has powerful experimental tools for understanding this genetic complexity in a model organism, the mouse, and applying that knowledge to human diseases.
With more than 1.1 million deaths worldwide caused by diabetes and its complications each year, reducing the human suffering and economic cost of diabetes and its handmaiden, obesity, remains a global public health priority. The Jackson Laboratory is in the trenches, unearthing the networks of genes at the root of these diseases.
Rick Woychik is president and CEO of The Jackson Laboratory in Bar Harbor.