I'm more inclined to believe the person you responded to given how often I saw the AHA heart check logo on some questionable cereals in the 90s.

Yeah, these cereals have soluble fiber...with a bunch of sugar.

The assertion of GP is incorrect about AHA not opposing smoking but I can’t find information about their historical sponsors.

The cereal thing is problematic but there wasn’t good data about this at first (which, itself, was due to corporate lobbying/grant-making)