How you can predict the way your current health decisions will affect your health in the future?

In my case, I know from experience and heredity that for example my father died of a second heart attack at least partly because of his high cholesterol. The high cholesterol was related to his high metabolism so that he ate a lot of eggs and bacon when young so that probably produced a lot of bad cholesterol. Myself I also have a tendency to high cholesterol and was warned by my dad's doctor to watch it so consequently I mostly avoid dairy products and egg yolk and beef (red meat) and am mostly able to control it that way with diet so haven't had a heart attack yet.