We live in a dimension where cause and consequences are not always clear and immediate, in particular about long term life-style decisions.
While it should be clear to anyone that jumping out of a 7th floor window onto a hard pavement is a bad idea, that will result in serious bodily harm, or even worse, most people will be able to reason that an extra piece of cake, once in a while, is not so terrible; or that an extra glass of this great wine will not provoke a headache tomorrow. Or that it would be a shame to throw away the leftovers from this nice roasted meat.
Once you have completed your anti-cancer cure, whether it was surgery, radiotherapy, chemotherapy, immunotherapy, or a combination of two or more of these, and you are in remission, the choices you are going to make are not innocent anymore.
The straw that broke the camel's back, or "la goutte d'eau qui fait déborder le vase", are two examples of an expression that means: there's always a last small step that provokes huge consequences!
Whether you manage to refrain fully from smoking will hugely impact your survival chances at 5 years and more.
Whether you manage you weight and limit your sugar intake will do wonders to your risk of adding diabetes to your list of worries.
Eating healthy, with a recommendation from a specialised nutritionist, based on your cancer history, will help you stave off relapses. After all, cancer cells consume a lot of energy in order to reproduce like crazy, so limiting fat, keeping a trim figure, taking up sports again, walking, meditating, cycling, doing yoga, all these activities will help ensuring a positive outcome.
And here's a lesson for all of us: don't consider all those choices as negative, look at them from the other side.
The issue here is not to limit yourself and take away one or more of your life's pleasures.
Consider not what you take away, but what you add to your life!
You don't limit your calories, you add to your tastes and get more pleasure from better food at reduced portions!
You add to your breath for each cigarette you don't smoke!
You add to your contentment by introducing walking, running, cycling etc to your weekly or daily routines!
Maybe, in the end, you won't add years to your life, but at least you'll add life to your years!