Science and Economics of Obesity

As scientists work to unravel the complex processes that regulate appetite, metabolism and weight management, each discovery and insight brings us closer to understanding weight gain and the challenges of losing weight, keeping it off and staying healthy.

More in-depth understanding of the body's chemical and hormonal regulatory processes can help researchers design drugs and therapies that target specific systems. One of those influential hormones studied at UMMC is leptin, which is secreted by fat.

Normally, leptin acts on the brain to suppress appetite and stimulate energy expenditure in the muscles and other tissues. But the more obese a person gets, the more leptin he or she produces, causing the brain to become increasingly resistant to some of the hormone's effects. In a leptin-resistant brain, the hormone raises blood pressure but no longer helps expend energy, and it doesn't suppress appetite effectively. That contributes to a cycle where an obese person burns fewer calories, feels hungrier and develops high blood pressure.

Through continued research, scientists can potentially design drugs that control leptin's effects, including its tendency to create high blood pressure, a major contributor to heart disease.

Tackling leptin is just one corner of the picture. For instance, at least 80-90 percent of people who've lost substantial weight regain it over time. Researchers are beginning to understand some of the factors contributing to these high recidivism rates - environment, behavior, endocrine and hormone system responses, genetics, neighborhoods, cultures and stress, among other factors - but unraveling exactly how some of those factors work is more difficult.

For example, levels of certain hormones, including ghrelin and peptide YY, in people who recently lost weight are different than in consistently slim people. In weight-loss groups, hormone levels indicate their bodies kick into starvation-response mode to try to regain the weight.

Given all the complexities that influence how we gain, lose and maintain weight, researchers need a full range of methods to uncover the science of obesity. From lab-based analysis of hormones and metabolism to psychological studies of food addiction, to population studies that follow groups of people through months and years, all these methods take financial support. The more scientists can discover about the many factors surrounding obesity, the more accurate and relevant knowledge we'll have to fight it.

Economics of obesity

The rising tide of obesity-related illness the U.S. costs about $150 billion annually, double the amount it was a decade ago, according to the Centers for Disease Control. That accounts for about 10 percent of all medical spending nationally. With greater than one-third of American adults obese and one in six children as well, the epidemic will continue to drive up healthcare costs. Obesity also increasingly undermines worker productivity. Obesity-related illnesses deteriorate the health and quality of the American work force and the viability of its future members.

In Mississippi, consistently ranked among the country's most obese states, poor work force health passes along hidden costs to businesses and the state. Obesity increases a person's risk for numerous chronic diseases - cancer, diabetes, cardiovascular disease and hypertension chief among them. While physicians can control many of those diseases and help people live normal lives, that care takes people out of their normal routines and, often, away from work. Uncontrolled diseases cause a far greater impact. Providing acute care for preventable illnesses - such as an ambulance ride and emergency-room treatment for a heart attack - drives up costs of private insurance, Medicare and Medicaid, and can create losses for hospitals if the person is uninsured. The more unhealthful our work force becomes, the more our costs of health care increase - costs that already threaten to overwhelm our healthcare systems.

Researchers estimate if trends continue, obese people will spend an on average more than $8,300 on health care annually by 2018, compared to the estimated $5,800 a healthy person will spend. Even if the national obesity rates remain stagnant, the cost of treatment is expected to jump another $50 billion annually to $200 billion. Those costs will further burden employers through health insurance rates and lost productivity when employees are repeatedly absent to receive care for preventable diseases.