“I can’t have a heart attack, because no one in my family ever has.”
“Everyone in my family has diabetes, so why bother trying to avoid it?”
I have no idea where beliefs such as these originated, but they span many diseases and are astonishingly common, even among the well-educated – my cousins included.
To my cousins and non-cousins: The world is just not that simple, nor that deterministic. Although family history certainly influences the odds of developing specific diseases, it is never the whole story. Even a disease that arises solely from a genetic cause, e.g. Huntington disease, is inherited, statistically, by only 50% of an affected parent’s children.
Instead, the odds of disease come from a combination of four factors: genetics, environment, behavior, and random luck. The good news is that the factor most amenable to change – behavior – matters a lot, especially in the major diseases that afflict Americans today.
The bad news is that, as medical science learns more about preventing disease, new preventive actions will be added to the already-long list of fun-spoiling behaviors that physicians will encourage.
What will be interesting is to see is whether insurers expand the practice of raising premiums for people who engage in anti-healthy behaviors. No doubt, plans are already afoot to raise rates for anyone who tweets their love of bratwurst.