As mentioned in Both Sides Now: Medications, some medications are essential, as they are hormones that the body can no longer produce for itself due to glandular dysfunction. Other medications act as dietary supplements. It's the medications that change how the body works which can cause problems.
Due to prostatitis, I had been prescribed the alpha-adrenoreceptor blocker Tamsulosin Hydrochloride at a dose of 400ug/day. This reduces constriction of sphincter muscles in the urethra, which alleviates urinary retention. However, it also affects arterioles, the iris in the eye, veins, the stomach, the intestines, male sex organs, the skin, the liver, pancreatic Acini & Islet (beta) cells, fat cells and salivary cells.
I stopped taking Tamsulosin and have had no problems weeing, so the prostatitis has gone. I'm now taking zero medications that change how my body works.
So eating less and moving more does have benefits.