The television and radio presenter told Good Morning America host Robin Roberts that he has had to cut out junk food after several health scares.
He revealed: "I can't have fast food anymore... no happy meals - I'm sad."
The 31-year-old, who has 10-month-old twins Morocco and Monroe with famous wife Mariah Carey, first suffered ill health in Aspen in January, when he was hospitalised for "mild kidney failure".
Cannon sought emergency medical treatment again in February for blood clots in his lungs and an enlarged ventricle in his heart.
He continued: "But I feel a lot better. That kind of food slows you down."
While claiming the new eating plan was "the worst thing" he also divulged that he has been ordered to get at least six hours' sleep by doctors, after usually surviving on two or three.
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Watch the Good Morning America interview in the video below: