GOLDEN VALLEY, Minn. — Your annual physical is supposed to be free, right?

So why does it seem like you always get charged when you ask questions about your health? Isn't that what a physical is for? Jonathon Hess of Athos Health has some answers for us.

First we need to look at why that physical is free. It's because it's covered by the Affordable Care Act (ACA), sometimes called "Obamacare." When this went into effect in 2011, the federal government was ensuring that everyone has access to free preventive (or "preventative") care. The goal is to make sure that diseases and issues can be caught early by your doctor.

Anything that falls under preventive care is fully covered by insurance, so you don't need to pay anything out of pocket.

Here's where it gets tricky.

If you have a clean bill of health at your annual physical, you're not going to pay anything. But if you go to your doctor and say something like, "My knee hurts," all of a sudden you might get charged for an office visit.

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That's because when you ask your doctor about something that's wrong with you, they're going to start trying to diagnose you and help manage your condition. That changes your visit from a preventive physical, to a diagnostic visit, Hess says. It's not preventive care anymore, and is therefore not covered under the ACA.

Unfortunately, there isn't exactly a solution for this. If you have an issue you need to ask your doctor about, you're probably going to have to either pay a co-pay, or pay for the full office visit if you are on a high-deductible plan and haven't hit your deductible.

You can either ask those questions during your physical, or schedule a separate visit. But the cost will likely be the same.

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One other important thing to remember: If your doctor and the lab that are doing your testing are not in-network, the services are not going to be considered preventive care. Your insurance company will not cover those out-of-network visits.

You can go to HealthCare.gov to find out what services are included under preventive care for all adults, women, and children.

If you have a question about your health care costs, or a topic you'd like us to cover in Health Care Hacks, email us at healthcarehacks@kare11.com.

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