99% of the population probably thinks their diet and exercise level is okay. They may admit it could be better.
99% of the population probably thinks their weight is okay other than maybe wanting to drop the 5 to 20 lbs they never seem to be able to drop.
The problem is that 40% or more of the adult US population is obese. A large percentage of the obese are morbidly obese. They take in way too many calories and exercise little if any other than walking to their cars. The food they eat that is typically not healthy.
If we look at the data for specific groups you will see that 56% of adult black women are obese.
That is the subgroup the CDC lists with the highest obesity rate.
Many adults in any age group have other comorbidities such as hypertension, diabetes, heart disease, lung disease, kidney disease.
So a large percentage of the adult US population will not be part of the 99.9% from the original posting.