Perhaps he should see a nutritionist as well. I had heard alcoholics lacked Vitamin B (not sure which one) along with others, I'm sure. Had a husband and two siblings who wouldn't quit drinking and they are no longer with us. I'm sure if they had gone to AA they would still be here. Their bodies couldn't take it anymore. Eat well, exercise, take vitamins and see a nutritionist.
Your post reminded me that I have read that depressed people are often low on Omega 3 and 6 essential fatty acids. They are fabulous for your heart, too.
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.