From the Star-Telegram: "At 140 pounds and 6 feet tall, Fagg is bone thin. But his body mass index of 20 puts him within the optimal range for health. He might appear frail, but he is strong enough to do yoga and cardio workouts. If anyone doubts his fitness level, the 60-year-old Fagg is quick to challenge them to a hike from his home in Hurst to downtown Fort Worth. In 2007, he hiked down the north rim of the Grand Canyon and up the south rim, for a total of 65 miles, 13 of them straight up. 'My goal is to hike it again at 75,' Fagg said. He sees no reason why he won't be able to make it. Like many followers of the calorie restriction, or CR, lifestyle, Fagg hopes to live to be 100. But life extension is not the reason he eats so little. For Fagg and others, it's the health benefits that matter. ... Since the 1930s, researchers have documented the health benefits of calorie-restriction in animals, including a reduction in certain cancers. Although not a lot of research has been done on humans, two studies found that the probability of someone who practices CR coming down with diabetes was virtually nil."