How do I(m31) convince my dad(m59), brother(m33), and sister(f27) that weight loss doesn't happen with diet suppression pills or a month of "pushup challenges"?

I've tried to tell them that exercise is only like 20% of what it takes to lose weight, and you can't out work a bad diet. But they just don't listen and every year I have to deal with them complaining and using the same arguments. Healthy food is too expensive, so and so went on this pill or did this and lost weight, I don't have time to meal prep, etc....

I know I'm not a good rep for weightloss because I've been over 300lbs for the last 3 years, but I've lost 25 lbs in the last 6 months.i just don't know how else I can convince them to go about this the right way or to point them to the right material(podcasts, TV shows, radio stations, books, etc....) to help them learn.

Anybody have any advice or input on this?