To any they may need extra support it doesn't take very much time to notice positive changes from living a healthier lifestyle. I have recently (as of a week ago) made drastic changes to my own and am feel a lot better already.
So far a lot of it has been very easy. More sleep and better eating. I make sure to try and get 7-8 hours of sleep and to start teh day off with a good breakfast. And throughout the day snacking on fruist and vegtables while drinking water as opposed to drinking high sugar drinks and snacking on junk food. Mind you I am a person that loves all of this bad stuff but the transition has been surprisingly easy. I think I just finalyl had it with beign sickly and not lookign as good as I want to and that is enough to drastically change my ways.
So to those on the fence, just figure out what do you really want of yourself? The hardest part of this is the mental choice. Once you have made it you will feel better and the choice will have been an easy one.