In the 1920s, while many MDs were being taught that a “normal” systolic BP was age + 100, life insurance companies increased premiums for hypertension.

Why? They had skin in the game.

Today, my life insurance company mailed me this mask.

Hmmm... could they be onto something?

In case you’re wondering about the attitude of MDs toward the treatment of hypertension at the time, here’s a quote from the premier cardiology textbook of the era:

The life insurance companies didn’t care about the logic of hypertension. They simply observed that their customers with high blood pressure were more likely to result in a loss for the company - and acted to protect their interests.