According to data from 2015-2016, about 40% of American adults are obese, meaning that they have a BMI greater than 30. In the same period, 7.7% of adults were severly obese, meaning that they have a BMI greater than 40. These numbers are significantly higher than the 33.7% and 5.7% reported less than a decade earlier, in 2007-2008. During the same period, childhood obesity only slightly increased.
There is no one single reason that adult Americans are continuing to get heavier, but several have been put forth as reasons for the "epidemic," including the decreased physical demand of American jobs, increased sedentary time due to electronic use (i.e. smartphones and TV), changes in sleep patterns and stress, changes in the bacteria in the digestive tract, and even the temperature of our homes and workplaces. Whatever the cause, Americans are clearly overeating and eating the wrong things: the article notes that fast food sales have risen by 22.7% from 2012-2017, and according to a study done by the Harvard School of Public Health, Americans are generally eating fewer fruits, vegetables, whole grains, and nuts.
At the same time, there has been a movement to accept a range of body sizes as healthy, based around the idea "Health At Every Size," which asserts that you can be healthy at any weight (or at least a range of weights beyond the traditional 20-25 BMI). Some people reject the idea of an obesity epidemic at all, and believe that people getting heavier is evolution, and not something to be concerned about.
I personally think that we should be concerned about the obesity epidemic, and conduct more research to find out root causes, particulary as children and adults are clearly experiencing something different. I can't really speak to the extent to which overeating is the cause as opposed to genetic changes, digestive bacteria, etc., but I suspect that it is more of a cause than people want to admit. I also think that believing in Health At EVERY Size is inherently flawed, but I do agree that we should accept a wider definition of healthy in general. For example, a person with a 26 (overweight) BMI who runs marathons is going to be healthier than a skinny person who does no exercise. Additionally, most fashion models that people tend to think of as "healthy and fit" are actually underweight, which is also not healthy. Finally, I want to add that I absolutely disagree with anyone treating others differently because of their weight. Even if someone is desparately unhealthy, that is not a reason to shame or bully them.
Thoughts on America's obesity epidemic?