Eating "regular" meals - small meals throughout the day would allow his body more time to break down the smaller quantities of sugars he's consuming throughout the day. As opposed to one great big dose once a day.

Eating like that really isn't very healthy for the average person, the body goes into a "starvation mode" and the metabolism slows down. Thus when he does eat - it doesn't get processed as quickly.

If his sugar levels remain THAT high all the time - he'll start to show damages to his body systems... the smaller blood vessels are most easily damaged -- his vision will weaken and he'll start to go blind as those areas behind his eyes get damaged... his feet & legs may start to show signs of damage. He won't be able to heal from injuries as quickly (small wounds like bug bites and cuts will take longer to heal and make him more prone to infections)

If he feels that he WANTS to change - he's going to need to totally change his eating habits... (probably change what he's eating as much as when / how he's eating it). He's going to have to get more exercise - burning more calories will also burn more sugar out of his system.

He may need to get an insulin pump installed... it's about the size of a pager.

I wish him the best of luck - this really isn't something he should be messing around with.