To understand the national health crisis associated with obesity, we must first look at the alarming increase in the incidence of obesity. Today one-third of American adults and one in six children are obese. In Mississippi, the statistics are even direr. The magnolia state consistently ranks among the country’s most obese, putting Mississippians at high risk for numerous chronic diseases including cancer, diabetes, cardiovascular disease and hypertension. But before we can take positive steps to stem the tide of obesity in our families, communities, state and nation, we have to recognize it. How do we know if we are obese? What is the difference between overweight and obesity. How is obesity diagnosed and defined?
Terms such as overweight and obese, certainly can be subjective, especially when we are describing our own weight or that of a loved one. But overweight and obesity are not strictly in the eye of the beholder. They can be quantitatively defined using scientifically and medically accepted standards based on Body Mass Index (BMI). Knowing where we stand on the BMI scale and calculating our risk factors is critical to taking charge of our health and improving our odds of living a long and healthy life.
The most common way to find out whether you are overweight or obese is to figure out your BMI, or the estimate of fat content in your body. It can help you gauge your risk factors for diseases that are related to a high volume of body fat.
For adults, BMI is calculated using a person’s height and weight. You can use the following table to learn your BMI. First, find your height on the far left column, and then move across the row to find your weight. Once you’ve found your weight, move to the very top of that column. This number is your BMI.
The previous table offers a sample of BMI measurements. If you don’t see your height and/or weight listed on this table, go the National Heart, Lung and Blood Institute’s website for a complete Body Mass Index Table.
BMI: 18.5–24.9 Normal weight
BMI: 25.0–29.9 Overweight
BMI: 30.0–39.9 Obese
BMI: 40.0 and above Extreme obesity
Although BMI can be used for most men and women, it does have some limits. It may overestimate body fat in athletes and others who have a muscular build. BMI also may underestimate body fat in older people and others who have lost muscle.
In addition to BMI, the diameter of your waist may be a factor in determining weight-related risk factors for adults. Persons with abdominal obesity, where most of your body fat is located around the waist rather than at the hips, are at increased risk for coronary heart disease and type 2 diabetes. The risk goes up with a waist size that’s greater than 35 inches for women or greater than 40 inches for men.
Overweight and obesity are defined differently for children and teens than for adults. Children are still growing, and boys and girls mature at different rates.
BMIs for children and teens compare their heights and weights against growth charts that take age and sex into account. This is called BMI-for-age percentile. A child or teen’s BMI-for-age percentile shows how his or her BMI compares with other boys and girls of the same age.
For more information about BMI-for-age and growth charts for children, go to the Centers for Disease Control and Prevention’s BMI-for-age calculator.
Less than 5th percentile Underweight
5th percentile to less than the 85th percentile Healthy weight
85th percentile to less than the 95th percentile Risk of overweight
95th percentile or greater Overweight
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 the Mississippi Center for Obesity Research (MCOR) 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,” notes Dr. Richard deShazo of the MCOR. “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.”
With continued research, scientists hope to develop drugs that control leptin’s effects, including its tendency to create high blood pressure, a major contributor to heart disease.
Researchers at UMMC are looking at risk factors for obesity, such as environment, behavior, endocrine and hormone system responses, genetics, neighborhoods, cultures and stress.
“The Medical Center also has developed a number of community outreach programs to increase health literacy and assist the public in understanding the importance of healthy personal choices to prevent obesity,” adds Dr. deShazo. “UMMC has trained and certified over 1000 lay advocates to function as health screeners and navigators in communities throughout the state. And, in collaboration with Mississippi Public Broadcasting (MPB), UMMC provides a daily, 1-hour, patient call-in radio program, “Southern Remedy,” with a strong focus on healthy choices and disease prevention. Similarly, UMMC has collaborated with MBP to produce “Southern Remedy” television documentaries about improving health, including an award-winning series on the Mississippi obesity crisis.”
In another arena, insurance provider, Blue Cross Blue Shield of Mississippi is helping lead the way in encouraging Mississippians to fight obesity and adopt healthy behaviors, by developing and supporting programs to reach the state’s individuals, businesses and communities. BCBS’s programs and funding are making a difference for children and adults throughout the state – from their Healthy Workplace program, to the BCBS Foundation’s Healthy Hometown awards, and healthy eating and exercise programs such as Let’s Go Walkin’ Mississippi, Walk to Run and Healthy Blue Lifestyle. BCBS is encouraging healthy habits in children and youth with its Get Ready to Run program and through the funding of health and fitness equipment and curriculum for Mississippi schools, as well as the Healthy School Awards program.
We can start at home by determining if we, or other family members are overweight and obese. We can make a commitment to adopt healthy habits to help reduce fat and calorie intake and increase physical activity. We can create a regular exercise plan for our children and ourselves. We can encourage more family outings involving physical activity, such as biking, walking, team sports, dancing, swimming, and hiking. We can serve our family fresh fruits and vegetables, whole grains, low-fat dairy, lean meats, poultry, and fish and provide easy access to healthy snacks. We can limit our consumption of fast food and sugary drinks. We can offer positive reinforcement to family members when weight loss goals are met. We can support community events that promote healthy weight loss and physical activity. We can encourage health and fitness policies and opportunities in schools and in the workplace.
Many of our problems with overeating and overweight in Mississippi are steeped in tradition and culture.
Changing how we cook and how we think about food may not be easy, but the potential rewards are great – most notably, reduced rates of obesity, more healthy Mississippians, a stronger workforce, lower healthcare costs and a brighter future for ourselves and our children.
Richard D. deShazo, M.D., UMMC Professor and Clinical Director of Chairman’s Office of Allergy & Immunology, received his Doctor of Medicine degree from the University of Alabama. He served residencies in pediatrics at Children’s and University Hospital in Birmingham and in internal medicine at Walter Reed Army Medical Center, where he also received fellowship training in microbiology immunology and clinical immunology. Dr. deShazo is board certified in internal medicine, rheumatology, allergy and immunology and geriatrics.