I like seeing this, but: "Correlation does not prove causation."
I have a serious, incurable medical condition. Getting healthier has dramatically improved my ability to sleep. So, while lack of sleep may well cause health problems, that relationship can run the other direction. I see nothing in this piece which addresses that possibility.
Most of mind-body connections go both ways. Do one and the other factor will improve. Improve the other factor and first will get better. It's almost never a one-way connection.
This is my concern as well. Already this thread is full of "duh" comments and I seriously doubt the issue is this cut and dry.
As someone else with a condition that affects sleep, I think it is safe to say there is a chicken and egg problem with these studies that has not been resolved, at least in many cases.
I have a serious, incurable medical condition. Getting healthier has dramatically improved my ability to sleep. So, while lack of sleep may well cause health problems, that relationship can run the other direction. I see nothing in this piece which addresses that possibility.