Dying or becoming severely physically/mentally ill is very likely going to significantly lower the output of your utility function, so it would probably be a very bad idea to ignore the low-hanging resources which can significantly extend the time for which you are alive and well. I have attempted to search LessWrong for a list of such resources, and haven't been able to find one.
Are there any books, websites, or posts that contain significantly low-hanging fruit in this area? If so, please list them in the comments below.
Do you have a more original source. I've heard about this, and would be interested to know if/how a causal link was established between flossing and heart disease
I'd just google scholar 'flossing' and 'cardiovascular'. It has been the subject of several studies.