While many may be incredulous, the largest body of evidence has found that fatness is not a risk factor for heart disease or premature death, even controlling for the effects of smoking. Ancel Keys and colleagues confirmed this nearly half a century ago upon examining 16 prospective studies in seven countries, as well as actual angiographic and autopsy examinations of 23,000 sets of coronary arteries which found no relationship between body fatness and the degree or progression of atherosclerotic build-up. And the most careful studies ever since have continued to support these findings.

Dr. Paul Ernsberger, of Case Western Reserve School of Medicine in Cleveland, Ohio, led a review of nearly 400 studies that was published in the Journal of Obesity and Weight Regulation in 1987 which corroborated these results. “The idea that fat strains the heart has no scientific basis,” he said. “As far as I can tell, the idea comes from diet books, not scientific books. Unfortunately, some doctors read diet books.”

http://junkfoodscience.blogspot.com/2006/11/obesity-paradox-1.html

Weight itself is not a health problem, except in the most extreme cases (i.e., being underweight or so fat you’re immobilized). In fact, fat people live longer than thin people and are more likely to survive cardiac events, and some studies have shown that fat can protect against “infections, cancer, lung disease, heart disease, osteoporosis, anemia, high blood pressure, rheumatoid arthritis and type 2 diabetes.” Yeah, you read that right: even the goddamned diabetes. ...

1. Poor nutrition and a sedentary lifestyle do cause health problems, in people of all sizes. This is why it’s so fucking crucial to separate the concept of “obesity” from “eating crap and not exercising.” The two are simply not synonymous — not even close — and it’s not only incredibly offensive but dangerous for thin people to keep pretending that they are. There are thin people who eat crap and don’t exercise — and are thus putting their health at risk — and there are fat people who treat their bodies very well but remain fat. Really truly.

2. What’s more, those groups do not represent anomalies; no one has proven that fat people generally eat more or exercise less than thin people. Period. And believe me, they’ve tried. (Gina Kolata’s new book, Rethinking Thin, is an outstanding source for more on that point.)

http://kateharding.net/faq/but-dont-you-realize-fat-is-unhealthy/

http://www.suite101.com/content/deadly-cost-of-physical-inactivity-a19241

Many of the health risks associated with obesity may be due to the poor diets and sedentary habits associated with fatness rather than the extra pounds per se.

http://reason.com/archives/2007/12/31/secrets-of-weight-loss-reveale

Children who seem healthy and of normal weight could have serious health problems because of the United Kingdom’s increasingly sedentary lifestyle, new research says.... Researchers from the University of Essex’s Centre for Sports and Exercise Science said that increasing weight gain did not explain the “large and worrying” falls in UK children’s cardiorespiratory fitness levels over the past decade.

http://www.bmj.com/content/339/bmj.b5646.extract