Apple's (AAPL -0.57%) Apple Watch is a bit of a niche product right now, but if Apple can figure out a way to use it to help diabetes patients track their blood-sugar levels, then it could become a must-own device for tens of millions of people in the U.S. alone.

In this clip from The Motley Fool's Industry Focus: Healthcare podcast, analyst Kristine Harjes is joined by contributor Todd Campbell to discuss a secretive program at Apple that's developing healthcare sensors for its devices.

A full transcript follows the video.

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Kristine Harjes: Let's turn to a company that I don't think we've mentioned yet on the show but is working in the space, and that's Apple.

Todd Campbell: Apple is obviously on the cutting edge when it comes to developing easy-to-use consumer electronics that resonate with people. That's the whole thing, the whole experience. So we were talking before the break, being able to figure out, we want to marry healthcare outcomes with technology with the information we've collected -- how do we do that in a way that really resonates with consumers? And one of the ways that Apple is trying to do that is through its Apple Watch.

Harjes: Right. The Apple Watch is a really interesting product, but right now it's kind of a luxury product. And I think if they're able to find a way to make it a must-have for diabetics, that's going to be a game-changer for this product.

Campbell: You have apps that tie into both your Apple phone, your Watch. Some of those are healthcare related. You have access to things like heart rate through these devices, being able to track those things. But wouldn't it be great, Kristine, if you could be wearing your Apple Watch and, at the same time that you're wearing it, it's measuring your blood glucose level?

Harjes: Absolutely, yeah. One of the big step changes with this project -- which, by the way, Apple is working on this. Despite Apple being shrouded in secrecy about what's next sometimes, a very credible journalist from CNBC reports that they are working in this area. So the step change that I see in this project is that they're looking at a non-invasive continuous glucose monitor sensor. When you talk about reading your glucose levels, it always involves some sort of prick to the finger, or something that is invasive to the body, What they're trying to do is figure out how the Apple Watch could incorporate an optical sensor to read glucose levels just by shining light through the skin, and integrating that with the data that you have on your Apple Watch.

Campbell: Which is pretty amazing. I guess the question would be, will that be shining continuously and measuring it continuously? Or will that only be shining at specific intervals? And how often will those intervals be? And that's going to create all sorts of design problems, because you're going to have to figure out, how do you make the battery lights last long enough to be able to do that, potentially?

Harjes: What happens when you're charging?

Campbell: Yeah. If we go back in time for a second, we've already made huge advances in doing this, as far as, you have companies like Medtronic that now have an artificial pancreas where you have continuous glucose monitoring occurring from a small sensor that is inserted underneath the skin, that you wear in a pump that's delivering blood glucose on demand as it needs to. You have other companies like Dexcom that are out there that are making huge advances in sensor technology, that are providing real-time, truly continuous readings that people are able to use to chart up and down their blood glucose levels to help them better figure out when they might be crashing, when they might need insulin or not need insulin, or whatever.

So Apple, I think you're right, it's a fascinating concept to be able to just use light, and be able to evaluate blood glucose. But it's not as simple as just saying, "Yeah, we're going to do this." I suppose that's why they haven't rolled it out yet, and why they're being so secretive. Supposedly, they're in the initial test phases of this to try to see whether or not this makes sense. They went out a couple years ago and bought a company that was working on sensors for healthcare to try and give them a little bit more experience in that area. It's hard for me to imagine, honestly, Kristine, that we get, 10, 20 years from now, and it's almost like going to be like we're having our doctor with us on demand. We're going to have so much information, so much data, that we're going to be able to collect just from the clothes we're wearing -- you can buy compression shirts and sleeves now that do a lot of these evaluations, too. They're looking at various different disease indications, being able to measure levels of certain proteins in your sweat to be able to see how your kidneys are performing, all sorts of interesting things that theoretically we could discover and be able to track over the course of the next 10 or 20 years. I think what Apple is saying is, "We want to make sure we don't get left behind in that movement."