This is from Outside Magazine. I found it informative. More article details by clicking link
First celebrated in chiropractor Douglas Graham’s 2006 book The 80/10/10 Diet, the all-fruit diet has long had a cult following: Steve Jobs, among others, was an adherent. But the endurance world took notice after long-distance runner and fruitarian Michael Arnstein, 36, won last year’s Javelina Jundred ultramarathon and placed third at the USA 50 Mile Road Championships. Other athletes who follow some version of a fruit-heavy diet include USA Masters 50K champion Tim VanOrden and world champion Jamaican sprinter Yohan Blake, who credits his success to a daily dose of 16 bananas.
“Since I started eating this way,” Arnstein says, “I only get better and better.”
Of course, there are lots of reasons not to jump on the trend. It would cost you almost $200 a day to fuel exclusively with fruit the way Arnstein does. Even scarier: some studies have linked excessive amounts of fructose, plentiful in fruits, to pancreatic cancer—which Jobs died from—and a fruit-only diet can lead to nutritional gaps, including iron, zinc, and B2 deficiencies. But there’s a growing body of evidence that high doses of the right fruits can be an outstanding source of energy—provided they’re not the only source.