http://well.blogs.nytimes.com/2014/01/15/what-ultra-marathons-do-to-our-bodies/?_r=1 offers a somewhat different view.
I used to be a 2-5 mile runner 3-4 times a week. I was in pretty good shape. Since 2001 I have run 39 marathons or ultra marathons. I've put together a spreadsheet of all my numbers from Dr visits and blood work and virtually every number has remained stable or improved, especially some very important ones like weight, BP, and good cholesterol. Significant improvements in some of them. And I feel a LOT better.
It's not for everyone, but my doctor agrees it works for me. I've run those crazy 50 milers, and in 8 weeks, at age 53, I will run 100 miles. My doctor would rather I not do it, but he understands why I want to do it and OK'd it, and just reminds me that the goal is to continue running as long as I can, and not to burn out trying to run too much now. I have no knee problems (other than a self-inflicted ski injury), my back is better as I keep weight off and do core exercises such as planks, and my hips are stronger with other targeted exercises.
As far as eating anything I want, maybe some people who run this much can, but I eat and drink in moderation. Otherwise my weight goes up when I am between races and running less, and doesn't come off as much when I am running more.
Right now I'm running slower and longer, but I felt like I was in even better shape when I was working on lowering my marathon time by including 1 or 2 speed workouts a week.
Those of you keeping to the recommendations in the OPs article--good for you! It may be the healthiest way, and at the very least adding more probably would get you diminishing returns. I think that any exercise or physical activity you enjoy and maintain is good, and running is too high impact for some. But don't worry about me running 50-60+ miles a week. I'm a whole lot healthier than a couch potato. At 58 my dad's heart needed to be restarted 5 times after a major heart attack and he was mostly inactive. Maybe I'm wrong and will keel over sometime in the next 10 years, but I'll take my chances on my lifestyle over what his was.
I think people can manipulate a running study to make it say about anything they want, and the media is happy to twist the study to make it worse. Time Magazine a few years ago had a cover story that said (something like) "Why Running Won't Make You Lose Weight". Turns out it was a bunch of anecdotal evidence like people who run often treat themselves to eating junk food and don't lose wait. If they had said "Why Running Might Not Help You Lose Weight" it would've been very accurate, but that doesn't sound nearly as appealing to their couch potato audience, does it?
:rant off