You don't have even have to encourage or be concerned of them "giving up" if your buying foods he can't resist. It's about discovering and leveraging his already existing vices. And then you slowly increase frequency and volume from there.
Once you identify the few key things he habitually consumes daily, examine the calorie content and see if you can exchange it for something higher calorie. Usually the higher calorie option will be tastier.
For example, my wife was buying a certain IPA she drinks when she gets home. I found an IPA with triple the calories and she of course thought it was amazing and she only drinks that from now on.
4 years
