There is an important difference between self-improvement and organic self-maintenance. As I have said many times, this work effort is not about self-improvement, building a better ‘me’.
There are so many flaws with the path of self-improvement that it is difficult to know where to start. The focus on self, the motives involved, the tawdry aims that always seem to arise, the shift from the present—the only time when anything ever happens—to the future, and so on. Certainly it is instructive to observe the tendency towards self-improvement and you can pursue it if you wish but you cannot defend it as part of your work effort, which is a preparation to serve other than yourself.
However, it is also important not to confuse the distraction that is self-improvement with the obligation to maintain the health required for you to perform your tasks. It is not self-indulgent to consider your organic existence and respect its needs. Observation of self should include noting the things that assist you in maintaining your health and your physical capacities. There are certain foods you should eat and others you should avoid. There are physical exercises that assist you in your work and others that do not. Reading and consulting with so-called experts can provide useful guidance on where to look but nothing beats your own patient and careful observations over time.
Your findings cannot be generalized to others. Missionaries can do a lot of damage by advising others to do what may have worked for them. Advising someone else on their health is a very serious matter. It is not just a matter of giving or getting the right advice. It also matters if you agree. The right advice may have to come at the right time and in the right way to be beneficial.
Finally, you need to resist becoming obsessed with your health. The aim of organic self-maintenance is to enable your physical organism to serve you faithfully and effectively. This requires discernment. When does attention to health stray from sufficiency of effort for practical purposes to obsessiveness? Only you can answer that question but the tell-tale signs will be found in the sensations and mental patterns that are triggered by thoughts about your health.