My Husband, 61, Received An A1C Of Around 8.3 In

My husband, 61, received an A1C of around 8.3 in Dec 2017, first time ever on a blood test. Started metformin and by March he was down 30 lbs (250 to 220, he's now at 208) and the first 90 day reading came back 5.2. We are thinking of trying the medication for about one year then see how he does without it...any thoughts? (Just prior to the initial diagnosis he had been away from home remodeling one of our homes to sell and he admittingly ate nothing but "junk food". Burger, tacos, etc and soda.). While I don't believe it just "happened" in the 10 weeks he was away from home, I was surprised by such a significant drop in the results so quickly.