Unhealthy Husband- I know there's no quick fix, but I'm really worried... Overweight & drinks too much?

Hi, I'm 30 and he's 36, we have been married for 4 months now. It's not that I'm trying to change him now we're married, I have always been concerned but didn't want to pressure him. We've been talking about starting a family soon and I'm concerned about his drinking and general health. He never goes a single day without drinking and drinks 1/2 to 1 700ml bottle of Rum each day. I said something about this the other day and he told me it's better than it used to be. We have been together 4 years and I honestly didn't notice how much he drank as he buys it himself, but always has a drink in his hand every afternoon. The only reason I've noticed now is he asked me to grab him 2 bottles Friday afternoon (they were on special) & they were both gone Sunday night. He is never aggressive or drunk but I worry about the health of his liver etc. He is carrying his excess weight in the stomach & chest area. I tell him he's not overweight, he just has a big belly (which is pretty much true). He also doesn't eat breakfast at all and it's not unusual for him to get home at the end of a 12 hour day to have eaten next to nothing all day. Then of course he makes up for this at dinner and snacks continuously until he goes to bed. I have suggested he have cereal at work that he can eat in the morning while at his desk. I also try to make sure he has something to take for lunch but sometimes he says he was too busy to eat. He does have a difficult and stressful job which involves both office and field work and he works 7 days a week most weeks. I would like him to be motivated to exercise etc but he starts work at 5am and I can't get up with him at 4am to go for a walk.. No way.. I do understand he is too buggered to go for a walk or do exercise in the afternoon. I just wish he could be healthier as I try pretty hard. I am fairly healthy, I'm 5ft 11" and weigh about 68kg. Hubby is 6ft 2" and weighs.. I have no idea he won't tell me. Any suggestions how I can encourage him to drink less, exercise more and eat healthy would be appreciated. Ps, I look young for my age & he looks old for his. He has been mistaken for my father before and this was embarrassing. I know he wants to change but lacks willpower or motivation.