Orson Scott Card, an author I have been following since I stumbled upon the short story, "Ender's Game" in Analog magazine in 1977, had a stroke in January, 2011. He claims he is embarking on a "save my life diet" (which is probably a low-fat, high carb diet), yet he reviews (and, apparently, samples) local donut shops.
He is a voracious reader and I really wish he would get around to reading Good Calories, Bad Calories or Why We Get Fat and What to Do About It, both by Gary Taubes. Why? So he can change his eating habits and live long enough to finish his uncompleted books, such as the Tales of Alvin Maker and the Ender's Game series. Plus several other uncompleted series (e.g., Pathfinder, The Lost Gate, the Women of Genesis, and the Mayflower trilogy).
Perhaps his stroke is pushing him to complete some of these unfinished series, as a new one in the Ender's Game series has just been announced: Shadows in Flight which comes out in November, 2011. This book follows Bean and three of his children as they seek to find a cure for their giantism.
However, there is no telling Orson Scott Card anything. He is the epitome of an opinionated, know-it-all intellectual (the kind he, himself often criticizes!), one who is often in error, but never in doubt. So I doubt he would take anyone seriously who suggested a low carb lifestyle. Because he knows better.