Extreme fad diets are couched in the language of optimization, but they only work if they reflect the real-world and will likely lead to an unexpected result.

From proteinmaxxing and fibermaxxing, today’s extreme fad diets are couched in the language of optimization. Health influencers and celebrities say we need to squeeze as much of these specific nutrients into our meals as possible to maximize how we look or how long we live. While it sounds nice in theory to strive for the best diet, what would that mean? The history of diet optimization suggests that the question itself is ludicrous.

To set the stage for optimal dieting, we need to go back to the early 20th century when scientists discovered that a constellation of mysterious illnesses, including beriberi, pellagra and rickets, was caused not by germs but by a lack of certain chemical compounds we now know as vitamins. As soon as a unified theory of vitamins emerged in the 1910s, public health officials sought to get the new science out to families to prevent illness and improve well-being.

Hazel Stiebeling — a Columbia University-trained chemist who had written her doctoral thesis on vitamins A and D — was one of the figures who took charge, leading the food economics division of the U.S. Department of Agriculture. Stiebeling modernized the department’s dietary recommendations to incorporate new scientific knowledge of vitamins, publishing her first plans with co-author Rowena Carpenter in 1936. During the Great Depression, their........

© San Francisco Chronicle