Two things that are undergoing rapid, transformative change -- media and public health -- seem increasingly intertwined.

In just the last two weeks, for instance, the media world witnessed the start of the new fall TV season (new series will start dropping like leaves any day now). And on Monday, Apple's latest plum, the iPhone 5, doubled the first-day order record of the iPhone 4. (In contrast to Newton's experience, however, this Apple defied gravity -- its stock soared to $700 a share.)

Meanwhile, just a day after the Apple feast, a startling study was issued that said by 2030 more than half of the residents in 39 states would be obese -- beyond the 42 percent estimate federal officials are using.

Obesity's link to other noncommunicable diseases (NCDs) led to the first high-level United Nations health meeting since one for HIV/AIDS in 2001 (as described in Wendy Bennett's accompanying commentary).

The threat (and cost) of NCDs are among the reasons the New York City Board of Health approved Mayor Michael Bloomberg's restrictions on super-sized soda last week.

How related are these trends? Are our screens -- be they TV, computer or mobile -- making the people who us them less mobile? And if so, to what degree do these technological transformations affect global health -- the subject of the Minnesota International Center's annual "Great Decisions" conference on Oct. 13?

Like the Minnesota International Center, local leaders in NCD research are thinking globally. Three of them -- Dr. Warren Thompson and Dr. Donald Hensrud, who both practice in the division of preventative, occupational and aerospace medicine at the Mayo Clinic, and Simone French, a professor in the division of epidemiology and community health at the University of Minnesota -- shared their thoughts on the potential links between changes in media and health.

"We are a nation of sitters, and I think it's had a huge impact on the obesity epidemic," said Thompson.

And this is true even if these sitters are also exercisers, said Hensrud.

"We've known that exercise is important, and the activity we do throughout the day is important," Hensrud said. But sitting seems to undermine health, he adds, "even when taking physical activity into consideration."

Some of this sitting is synced to screen time (they're called laptops, after all). Nielsen's 2012 "State of the Media Cross-Platform Report" estimates that Americans spent five hours and 28 minutes per day in front of screens. And it's not just connected kids. In fact, usage among those under 18 is lower than it is for people the age of their parents and, especially, their grandparents.

To be sure, it's not necessarily screens, but how we interact with them -- mostly sitting -- that may be so insidious.

"There's nothing magic about computer or TV time," said Hensrud. "It's probably all a surrogate for sitting."

And other factors are in the mix beyond media's link to sedentary behavior.

"Obesity is a multidetermined health affect," French said. "It's not just TV, but a whole cultural package of things, about the types of foods we eat, portion sizes, sugar-sweetened beverages, and cars, that are contributing to obesity. But TV is one pretty clear, pinpointed factor that is pretty robust, so we can point to that as an influence."

French said that the obesity epidemic "started in the 1980s, and has not shown any signs of leveling off."

That also happens to be about the same time of mass adaptation of cable TV, and right around the time Apple's iconic "1984" Super Bowl ad heralded the age of personal computers.

If cable had us sitting more at home, computers did the same at work, where nowadays labor is not so, well, laborious.

"The differences are huge, and yet we're blaming people for their obesity. Of course there is the issue of personal responsibility. But we also have a responsibility to improve people's environment," Thompson said. "It would behoove us as employers to devise solutions."

French and Hensrud also said that personal and professional changes were needed to combat a multipronged problem. French noted how constant commercials may prompt people to eat, which creates "a double risk."

And Hensrud rightly reflected on how powerful these changes and resulting challenges have become, how likely they are to stay, and how we need to find some kind of balance between media and health trends.

"We're not going to avoid technology. But we are ignoring a whole bunch of things that we do know. Unlike years ago, we have a lot more choices than we did -- the knowledge base is there.

As we embrace technology, I hope that we can reverse some of this, and also embrace the knowledge that we have to use technology for its benefits, but not let it control us to the point where it's negatively influencing our health as much as it may be."

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John Rash is a Star Tribune editorial writer and columnist.