We had a rescue come in that was so obese we didn't know if he would make it with the strain on his heart and his legs. He could barely walk 1/2 block so we put him on the pumpkin diet that was recommended by our vet. He loved the pumpkin (we hated having to clean his face) but it worked. We also walked him every night, slow steps but as he started to lose weight he started walking faster and longer
People don't know how to get their dogs to lose weight without all the side effects - begging, that sad-eyed look that says "I'm hungry", etc.
Try the pumpkin diet. Reduce your dog's regular food by 33% and replace it with a 67% volume of canned pumpkin (
not the kind with sugar and spices, ready-made for pies). For example based on a large dog, if you are currently feeding your dog 3 cups of food, you would instead feed him 2 cups of food and a whole cup of canned pumpkin. Dogs love the pumpkin - it has the texture of canned dog food, it provides vitamins and roughage, it makes them feel full (so they don't forage in the yard for leftovers), and they lose weight!
The only treats he got were the baby carrots.
Good Luck and remember
no one can feed him treats if you want your little one to live a good long life. You will determine that.