It's very important to consider "metabolic rate" in these considerations. I have been nearly under-weight my entire life (I'm in my 60s) and I've eaten as much

It's very important to consider "metabolic rate" in these considerations. I have been nearly under-weight my entire life (I'm in my 60s) and I've eaten as much high-calorie food I've felt similarly, usually a large amount (generally consuming the most any gathering I'm at, etc, eating three meal a day, etc). The one thing I've always done is avoid foods with added sugar and in general processed food. There's good evidence that the consumption of "ultra-processed" food is associated with the obesity epidemic and that these food are what people weight-maintenance processes out of balance. Given this, adding a drug to solve that problem might not be a panacea. What other bad effects could result from a strong drug plus a crap diet? We'll start another mass experiment to find, I suppose.