I have a huge sweet tooth too. It runs in my family. It really helps if you take a sliver and eat it with the tiniest little olive fork. This way it lasts a long time and I feel more satisfied afterward. Make him eat his pie with chop sticks.

Blindman eating pie with chopsticks..I may have to take pics of that one lol.
He just finished the last of the pie. I told him no more of that for a while.

Why not make more fruit-type desserts - and possibly use Splenda instead of sugar. Try some frozen yogurt-type desserts as well.
Short walks - even walking slow will help.

He wont eat any kind of fruit.
Im going to try that splenda trick as soon as I get to the store.