I wouldn't try to start anything, especially bodily related, until Pluto moves in Aqua (Jan 21st 2024). Pluto in Cap is endgame energy, my recommendation is to focus on gentle self care until the new year, maybe think and plan, but wait for the switch and then consider establishing new habits. This current energy is good for healing and releasing, especially with Venus in Scorpio, in the sense of acceptance and self care but trying to initiate things could be like pushing a rock up a hill. 

Also, I have skin stuff too since Pluto went back into Cap. Skin is an emotional conduit. I'm finding taking turmeric capsules very helpful, with pure Aloe Vera gel or Calendula used externally. 

I would say Mars or Saturn 6th House transits. Currently Saturn is in my 3rd House and I cut off coffee few months ago so I think it is also favorable transit for quitting substances.

Little update: could not find the exact reply, most have been in another topic, but someone here told me to wait for Saturn returning to the exact position as it was in my solar return (5°11' Pisces). The last 2 days I experienced a total change in my habits, suddenly I could do it! Must be the combo of the Sun-Pluto conjunction in Aquarius together with Saturn on this exact degree again. Whoever it was: she was so right! I happen to realize it now. Let's see if it last, but I have a good feeling about it!