“I think the notion of ‘calories in vs. calories out’ is ridiculous.” So begins a recent online article about diet. Typically, it cites no external sources of information for this opinion. Actually, the calories in – calories out equation is a truism; thermodynamics doesn’t make exceptions, and one way or another, those input calories have… Continue Reading
food
The Inefficiency of Humans
The human body converts the energy contained in food to mechanical output with an efficiency that may surprise you — it’s that low. What goes on at the gym reflects this. A person dedicated to keeping reasonably physically fit might use a rowing machine, an elliptical trainer, or a stationary bicycle. These machines usually provide… Continue Reading
The big fat myth
Tens of thousands of grocery store items play up the fact that they are “reduced-fat”, reflecting both the US government’s advice about eating less fat, and our concerns about becoming overweight or obese. Our food-shopping habits have changed over the past fifty years, as warnings were posted by the American Heart Association, the US department… Continue Reading
Life Expectancy II: It’s in the Genes
(Microscopic image of C. elegans with Nomarski DIC optics: by permission, Prof. Sander van den Heuvel, Developmental Biology, Universiteit Utrecht. About 200x lifesize.) How long can we expect to live in the future? The longest recorded human life is that of a French woman, Jeanne Calment, who died aged 122 and a half, in 1997…. Continue Reading
Save the Environment — Don’t Walk, Drive a Car
(Image credit: Wellcome Library, London “A Man Walking”, Image V0048616, Collotype after Eadweard Muybridge, 1887.) The idea that driving a car is better for the environment than walking sounds like the raving of an antediluvian climate change denier. Of course there is personal benefit in walking, and all of us should walk more, not less. But… Continue Reading