They are not luxuries. Modern society has just made it easy to neglect these things for various reasons. The lies we tell ourselves about it not mandatory until you burn out or need medical intervention.

Modern medicine will provide various interventions to help out such as trying to balance your brain chemistry, lowering obesity, blood pressure, etc. Many of the things prescribed to us today are due to lifestyle choices.

There's a growing corpus of evidence that diet has incredible potential for treating serious brain disorders (when done with a psychiatrist, especially if you're already medicated)[0].

At the end of the day, you are the only person who sets the priorities in your life. If you don't make maintenance of your body and mind a priority, the bill will come later.

[0]: https://www.goodreads.com/book/show/61129785-brain-energy