What your last heart screening REALLY did to you

Back when I was a kid, comic books would use radiation exposure to transform regular people into one of two things: either superheroes or supervillains.

Today, those same characters have moved from the comics to the big screen, where they earn billions at the box office.

And that radiation?

It's also worth billions -- at the hospitals, clinics, medical offices, and imaging centers that use it for X-rays and CT scans.

But while they make big money off those tests, the patients who get scanned don't turn into heroes or villains.

They could suffer serious, lasting, and even permanent risks.

Now, the latest research reveals just one of the tolls of all that extra radiation exposure, and it's not the cancer risk that usually gets all the attention.

Radiation from imaging tests can hurt you in other ways, too, by damaging one of the most essential parts of your cardiovascular system: your coronary arteries, which supply blood to the heart itself.

How's that for a terrible irony?

The very same CT scans a doc uses to check on your coronary arteries can actually damage those same arteries.

But since it won't happen right away, the test itself won't even reveal that anything is wrong!

Even moderate levels of exposure -- the amount you'll get from a few CT scans spread out over months or even years -- can cause damage the endothelial cells so that they pump out less nitric oxide.

Nitric oxide allows your blood vessels to relax so blood can pass through more easily. When you have less of it, the arteries could get tighter, making blood flow more difficult.

Cells hit by radiation also have higher levels of damaging oxidative stress and signs of more rapid aging.

The study finds it could take several years for this damage to take effect -- but once it kicks in, it could be permanent.

That's bad news if you're healthy.

But if you've had a few scans, odds are you have a few ongoing health concerns -- and that damage could take an even bigger toll, causing heart disease or making the condition worse if you already have it.

It's time to take a smart approach to scans.

If your doc absolutely needs an image, then of course go ahead and have it taken with as many precautions as you can.

But if you ask, sometimes there might be other options.

In some cases, an MRI will do the job just fine -- and those involve no radiation at all. In others, your doc could decide that a "just in case" scan could be skipped -- for now -- and revisited later if it turns out you need it.