The first issue that has to be addressed is nutritional deficiency.    Until deficiencies are addressed, nothing will work except extreme malnutrition because the brain will continue to perceive scarcity.   Care needs to be taken with supplements, however, the right ones, in the right amount, at the right time, are invaluable.   In order to achieve that reliably for anyone who has a significant problem with their weight, testing needs to be done. 

As for cost,managing a nutritional deficiency is far less expensive than taking most prescription drugs.  It's important to be aware that all of the longstanding drug manufacturers were originally vitamin manufacturers.   They switched tracks sometime not long after World War II, when it became clear drugs were where the money was.

The calories in/calories out fable is a scam that's not even grounded in basic biology.   The diet industry is massive, and how many people maintain the weight loss beyond a couple of years?  Fewer than 3% do.