Apple is secretly working on many things in the health arena, CEO Tim Cook said in an interview published on Monday, but only some of them are expected to translate into revenue-generating businesses.

"There's much more in the health area," Cook told Fortune. "There's a lot of stuff that I can't tell you about that we're working on, some of which it's clear there's a commercial business there. And some of it it's clear there's not. And some of it it's not clear. I do think it's a big area for Apple's future."

The CEO explained that some current efforts, like ResearchKit, don't have a business model, and are simply born of an interest in improving society.

"Will it [ResearchKit] eventually lead us somewhere? We'll find out. I can't answer that today," he commented.

The company does incidentally benefit, however, since ResearchKit relies on data gathered from iPhones and Apple Watches.

Apple's next health-related product is likely the Apple Watch "Series 3," set to premiere at a Tuesday press event. Its main feature should be LTE, but there have also been rumors about "smart bands" and/or glucose tracking. The latter might make the device popular with diabetics wanting to avoid invasive tracking.

In other segments of the interview, Cook addressed topics like the high cost of Apple products, and the seeming contradiction with that and aiming to make products for everyone.

"But if you look across our product lines, you can buy an iPad today for under $300. You can buy an iPhone, depending upon which one you select, for in that same kind of ballpark. And so these are not for the rich," he insisted. "We obviously wouldn't have over a billion products that are in our active installed base if we were making them for the rich because that's a sizable number no matter who's looking at the numbers."

On the subject of setting up an Apple charitable foundation, Cook argued against making altruistic efforts a "separate thing," and suggested that the company's initiatives have more impact because they have the entire workforce behind it, rather than a relative handful of people.

Cook took a defensive stance on issues like the distractions caused by Apple devices, and whether or not corporations in general benefit the world, given the socio-political and environmental damage they can cause.