The Science of Losing Battles

New research illuminates why most dieters regain lost weight. It’s even more complicated than we thought

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An old saying posits that the definition of insanity is doing the same thing over and over and expecting different results. If the $60-billion dieting industry is any indication, our society is steps away from a straitjacket. Despite copious evidence that most diets fail in the long term (beyond two years), many people repeatedly attempt to shrink their bodies, and the majority end up heavier than when they started. As Daniel Engber details in this issue, science is no closer to understanding why weight loss from dieting doesn’t stick. What we know so far is that a complicated interplay of factors leads to scale bounceback—from levels of hormones such as the hunger hormone leptin to the shape and size of fat cells and hereditary genetics (see “Unexpected Clues Emerge about Why Diets Fail”).

Elsewhere in this issue, Kendall Powell reports on a new path of research that is harnessing the innate competitive nature of cells with the hope for novel cancer treatments (see “Survival of the Fittest Cells”). And Robin Lloyd investigates harmful emissions from the plastics contained in so-called cured-in-place pipes, which are commonly used in sewer pipe renovation (see “Health Concerns Mount as More Old Sewer Pipes Are Lined with Plastic”). It never fails to surprise me that the science of health and medicine can touch nearly every human industry—from marketing diet shakes to the manufacture of construction materials. If we’re lucky and wise, our discoveries will lead to improved health and welfare for everyone.

Andrea Gawrylewski is chief newsletter editor at Scientific American. She writes the daily Today in Science newsletter and oversees all other newsletters at the magazine. In addition, she manages all special editions and in the past was the editor for Scientific American Mind, Scientific American Space & Physics and Scientific American Health & Medicine. Gawrylewski got her start in journalism at the Scientist magazine, where she was a features writer and editor for "hot" research papers in the life sciences. She spent more than six years in educational publishing, editing books for higher education in biology, environmental science and nutrition. She holds a master's degree in earth science and a master's degree in journalism, both from Columbia University, home of the Pulitzer Prize.

More by Andrea Gawrylewski
SA Health & Medicine Vol 2 Issue 1This article was published with the title “The Science of Losing Battles” in SA Health & Medicine Vol. 2 No. 1 ()
doi:10.1038/scientificamerican022020-4AcKl9rPz9i0NmGNz2mm5K

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