It seems like you can see health starting to decline from your 40s

I hear news about cancer patients quite often in their 40s.
People who are sick really look like they are suffering from something.
It seems like people who don't take a single pill, have good complexion, good kidney function, and good weight are actually rare.
For someone in their 40s, not taking any medication would be the ideal state (excluding those who don't take meds even though they are unwell. I have an obese friend with high cholesterol and diabetes who doesn't take medication..)
While innate health plays a part,
it seems those who stayed away from alcohol, smoking, and stress and exercised consistently fare a bit better.
Up until your 30s, everyone seems equally healthy,
but in your 40s, signs start to appear (whether your health is good or bad),
and by your 60s, the decline becomes unmistakable.
People who are sick at that age look visibly ill. ㄷㄷ
On the other hand, healthy people look like they'll live to be 100.