What do a svelte marathon veteran and a 400-pound sumo wrestler have in common? Both completed the Los Angeles Marathon yesterday, and their personal stories are testaments against the conventional “wisdom” of anti-obesity crusaders.

Long-time distance runner Joe D'Amico challenged himself to eat only fast food in the 30 days before the race. (This is a big no-no to food scolds since fast food is “processed” and may be high in calories, fat, and sodium.) But D’Amico proved the food haters wrong, finishing with a personal best time of just over 2 hours and 36 minutes. Running just one mile in under 6 minutes isn’t too shabby, but D’Amico averaged less than 6 minutes per mile throughout the entire 26.2-mile race.

Meanwhile, 40-year-old sumo wrestler Kelly Gneiting didn’t exactly keep pace with D’Amico. In fact, his time was nearly 10 hours. But he did set a Guinness World Record for the heaviest man to ever finish a marathon. Despite being obese, Gneiting says his blood pressure is normal and his resting heart rate is 60 beats per minute, which is on the healthy end of the scale for Americans. (Must be all that belly-bumping exercise.)

We don’t endorse extreme obesity, or eating fast food every day. But it’s worth noting the implications of these two men’s stories. First, there’s no such thing as “junk” food; even the much pilloried fast food doesn’t fit the bill. (Sorry, Morgan Spurlock.) Eaten in moderation and combined with exercise, any food can be part of a healthy lifestyle.

Second, more and more science is determining that being “fit and fat” is healthier than being unfit at a “normal” weight. A 2009 British Medical Journal commentary found that “obese men who were moderately/highly fit had less than half the risk of dying [from cardiovascular disease] than the normal-weight men who were unfit.”

Similarly, research published in JAMA (the Journal of the American Medical Association) found that the risk of dying was far higher across all weight categories for those who were unfit. And a 2010 report in the European Journal of Epidemiology concluded that leisure-time physical activity is associated with a reduced risk of death in middle-aged men, regardless of their body-mass index.

There’s always some political noise about taxing certain “bad” foods, and in fighting a War on Obesity. But if these two physical specimens can actually finish a marathon, maybe we’re fighting that war on the wrong front.