What you eat, what you expose your body to (stress, chemicals,etc), how much you sleep and exercise all influence which road you travel on. For example, if there is a strong family history of heart disease and you choose not to exercise, to eat a poor diet, and have a stressful job; then you will most likely travel down the road of having years of poor health and end with a heart attack.
On the other hand, if you choose to eat an organic, whole foods based diet, exercise regularly, practice yoga/meditation, etc.; then you will most likely live your life with energy and vitality. You still may die earlier than your friends due to genetics but you will have lived life to its fullest.