It may be that caloric intake is not directly correlated to weight gain or loss but modulated by your body's ability to extract calories from foods. The ability to extract calories is partly a function of the micro-organisms - which vary from person to person, in our gut.
A person who can extract more calories from food may be genetically blessed in a feast or famine environment, because they can store fat for the famine to come. Unfortunately as all of us super-sizers know, there is no shortage of tasty foods to eat in the good old USA.
Ms. Henig writes the following about Jeffrey Gordon the director of the Center for Genome Sciences at Washington University -
"Gordon likes to explain his hypothesis of what gut microbes do by talking about Cheerios. The cereal box says that a one-cup serving contains 110 calories. But it may be that not everyone will extract 110 calories from a cup of Cheerios. Some may extract more, some less, depending on the particular combination of microbes in their guts. “A diet has a certain amount of absolute energy,” he said. “But the amount that can be extracted from that diet may vary between individuals — not in a huge way, but if the energy balance is affected by just a few calories a day, over time that can make a big difference in body weight.”"
