Actors and actresses and models do maintain very expensive regimes (with things most people cannot afford like a dedicated fitness trainer or nutritionist, let alone a team) that can be unhealthy to do in and of themselves. Most male actors have talked about how punishing their regimes are , like Christian Bale rapidly gaining and losing weight: https://www.cinemablend.com/news/2465697/christian-bale-admi...

Diet/body image also have a massive industry pushing dodgy easy methods to consumers willing to spend. Anorexia and bulimia were glamorized with celebrities publicizing their 1200 calorie diets. Fen-phen, a weight loss drug, was the most costly recall of a drug ever with over $14B awarded in liability suits.

People are unhealthy, yes, but the media and entertainment do not have a great track record of pushing actually healthy habits.