One of the more important insight practices we find in the suttas comes from AN 5.57:
The Five Daily Recollections
I am of the nature to grow old; I cannot avoid ageing.
I am of the nature to become ill; I cannot avoid illness.
I am of the nature to die; I cannot avoid death.
All that is mine, dear and delightful, will change and vanish.
I am the owner of my karma; I am born of my karma; I live supported by my karma; I am related to my karma; Whatever I do, whether good or evil, that I will inherit.
If we think of the Relative and Ultimate views of reality, these five practices are obviously Relative practices. They speak of "I" and "mine" and ownership - all Relative concepts. And this is how they are taught - which is fine - we need to be able to operate from both the Relative and the Ultimate perspectives.
What's not so obvious is that these practices can also be viewed from from the Ultimate perspective as well:
The Ultimate Five Daily Recollections
"I" is of the nature to grow old; ageing cannot be avoided when "I" is conceptualized.
"I" is of the nature to become ill; illness cannot be avoided when "I" is conceptualized.
"I" is of the nature to die; death cannot be avoided when "I" is conceptualized.
All that is "mine," dear and delightful, will change and vanish.
"I" is the owner of the conceptualizer's karma; "I" is born of the conceptualizer's karma; "I" lives supported by the conceptualizer's karma; "I" is related to the conceptualizer's karma; Whatever "I" does, whether good or evil, that will be inherited by the conceptualizer.
Aging, illness and death only occur as a problem when there is the concept of an "I" that is subject to these. The Buddha's escape from dukkha was to overcome the delusion of Self. Aging, illness and death still happen to the body of one who has overcome the illusion of Self; it's just not a problem any more because it's not experienced as happening to anyone. Of course overcoming the delusion of Self is a rather difficult job, but this is the ultimate breakthru on the spiritual path. And even if you don't manage to fully uproot the delusion of Self, any movement in that direction does have a lessening effect on the severity of dukkha experienced.