There was a time when I was burning the candle at both ends. For some relief I would regularly go and see a Chinese doctor for massage therapies, but they would do a health check that included looking at my tongue. During this time from stress and lack of sleep my tongue was unusually white. The doctor said if I kept my life style I would have a stroke.
I listened to the advice and made big life changes. A friend of mine in a similar job sadly didn't receive the same advice and had a stroke.
Fixing bad sleep forces you to fix habitual bad patterns. Which in effect helps restore health and ingrain healthy life patterns