Obesity has reached epidemic proportions in the United States. These increased body fat reserves are associated with an increased risk of numerous health problems, including coronary heart disease and heart attacks, diabetes mellitus, stroke, some cancers, and more. Obesity has become so prevalent in the U.S. today that it is difficult to remember that just a couple decades ago, the average American was not overweight, and few were obese. Below is a link to an animated graphic showing the remarkable increase in obesity in U.S. states over time. In the ideal case, the entire map would be colored the aqua color, since there would be data from every state but no obese people.
This is the first frame. See animated version.
As is commonly done, obesity is defined here based on the body-mass index (BMI). The BMI is calculated by dividing one’s weight by one’s height squared. It is traditionally given in SI units (that is, kg/m²), so if U.S. customary units are used, they must be converted. BMIs in the range from 18.5–25 kg/m² is considered normal or healthy. 25–30 kg/m² is overweight, and greater than or equal to 30 kg/m² is obese. (40 kg/m² or greater is often considered morbidly obese, or sometimes 35 kg/m² or greater along with other risk factors is included.) The use of BMI is imperfect (for instance, a very muscular person will have a high weight and therefore BMI), but in practice it is usually simple to differentiate obese from muscular people.
For instance, consider a 1.78-m (5 ft., 10 in.) tall person. The healthy range would be from 58.5–79.0 kg (129–174 lb.). Those weighing more than this would be overweight, and over 94.8 kg (209 lb.) would be obese. For a 1.63-m (5 ft., 4 in.) tall person, the healthy range would be from 47.4–64.0 kg (104–141 lb.). Greater than 76.8 kg (169 lb.) would be obese.
It’s easy to calculate your own BMI. There are plenty of BMI calculators and BMI charts on the Internet. But the fastest way is probably to use Google Calculator: just type your calculation directly into the main search box (see example).
The obesity data are taken from the CDC. I reformulated them into an animated GIF since I didn’t care for the original color scheme and also because that presentation isn’t easily exported to other sites. You are free to use the image (direct linking is fine), though I would appreciate a link back here if you do.