How do I change my dog's portion size gradually without upsetting its stomach?

Digestive upset from feeding changes is much more commonly linked to switching to a genuinely different food, with different ingredients and formulation, than to simply eating more or less of the exact same food the dog is already used to.

This means a portion size change, on its own, is generally safe to make more directly than a full food switch, though a gradual approach still has real behavioral and comfort benefits worth considering.

Adjust the daily total by around 10 percent every one to two weeks when making a meaningful change, whether increasing or decreasing, rather than jumping straight to the full new target in one step.

This gradual pace gives you multiple checkpoints to monitor body condition along the way, catching an overcorrection early rather than only discovering it after several weeks at the full new amount.

If you are changing both the portion size and the food itself at the same time, such as moving to a new brand as part of a weight management plan, use a proper food transition over seven to ten days, mixing increasing amounts of the new food with decreasing amounts of the old, alongside the portion size change.

For a portion change alone with no food switch, the main reason to go gradually is comfort and easier monitoring, not a strong risk of digestive upset.