Something doesn't add up. The entire Japanese healthcare system is built around the idea that preventative testing for asymptomatic conditions is effective. You can read all about it, if you want.
Personally, I think you've swallowed some kind of health insurance industry black pill, whether you know it or not.
>You can read all about it, if you want.
I don't need to, I've lived in Japan and done the Ippan Kenshin which is the once a year health checkup. It consists of getting your weight, height blood pressure measured, an eye test, urine tests for diabetes and a blood test for cholesterol. That's very reasonable.
The one thing some doctors still tend to do is a chest-xray, which is not reasonable. They do it because tuberculosis was widespread in post-war Japan and they just kept doing it, but it has no positive impact on mortality rates.