I wish we could do this trial:
Enroll a large group of overweight patients with the same disease. Randomly assign each patient to one of two groups.
Both groups would receive the same treatments for their disease and would perform the same amount of exercise every day.
The first group would eat a nutritionally balanced diet that keeps their weight within one pound.
The second group would eat a nutritionally balanced diet that causes one pound of weight loss every two weeks. Once these patients reached their ideal weight, they would be switched to the same diet as the first group of patients.
Then compare morbidity and mortality over time,
This study is fantasy. It would be just about impossible to conduct.
But maybe researchers can look at all those patients whose disease remains stable or improved over time, whatever their weight. Within each group, they could then look at patients' weight. Of the patients whose disease remains stable, how many remain obese and how many lose weight?
As an educator presented with the Obesity Paradox, I would avoid the false dilemma of choosing between fitness or leanness. I would not suggest that obesity confers benefit.
Rather, I would embrace the paradox as an opportunity to continue exploring the differences in physiology between obese and normal-weight patients. Greater understanding leads to better treatments.