Some friends who were "old timers" in AA even back in the 70's had nasty nutritional deficiencies by the time they got to the program.
They were big advocates of balanced vitamins (nothing too whacky and guided by a nutritional physician), vitamin B therapy, and changing the diet to more proteins and vegetables and less carbs (esp. sugars).
Seems pretty conventional these days but they looked pretty healthy for folks in their 60's who'd done 30 years of hardcore boozing.
I still take about 5 things every morning--
One-A-Day multi
B Complex +C
Fish Oil
Flax Oil
Ginkgo Biloba