It’s time to end it:

…if one has been teaching that high-fat diets can lead to heart attacks for 30 years but then finds that this may not be true, or that, indeed, more fat and less carbohydrate in the diet may be beneficial to one’s health and longevity, feelings of discomfort can result. Subconscious mechanisms may then keep enduring convictions firmly in place for extended periods of time, despite evidence to the contrary.

And it’s hard to confront the fact that you may have been responsible for the poor health and lives cut short of people you’ve been advising.