Some natural lines are MyChelle (recommend highly) and Dr Hauschka.
You have adult acne at 70??? My dad, rest his soul, did too and was on Tetracycline for it. It did keep it checked. Maybe it's the products you use - my skin gets blemishes too if I don't cleanse thoroughly or use products that are wrong for me.
You could have reactive acne if you are using products which are too harsh for your face. I suggest the SIMPLE range. The products have no perfume nor colour and are kind to skin. They help with sensitive skin which I suspect you may have also.
The facial scrub will remove dead skin cells for brighter skin. The cleanser is kind to skin and purifies. The toner will soothe your complexion and has no alcohol.
With regard to moisturising, you could try 'Elave' intensive cream. This moisturiser contains certified organic ingredients.
All products are available on-line, although you can purchase 'SIMPLE' products in chemists in the UK.