Sunday, February 17, 2019

Retrospective #1: A Very Brief (and Necessarily Selective) History of Human Nutrition (and Dieting)

In the beginning, there were the hunters and the gatherers. In the History of Nutrition this was the Paleolithic Era, hence the Paleo Diet. In most cultures, men hunted and women and children gathered food as it was available to them. Early humans adapted to periods of feasting and starvation (fed and fasting states, in dieting terms).
We humans were of necessity omnivorous. It was a survival thing. We ate every part of the animals we were lucky or skilled enough to trap, club or impale. Every part of the animal (or fish), including the organ meats (offal), the blood, and even the marrow within the bone cavity, was eaten. Some of us still enjoy these foods today.
We also ate the things we could gather from in-season fruit trees and vines, and the leaves, roots and fungi that didn’t kill us. It was a trial and error thing. We learned that to survive we had to take risks, both in hunting and gathering, and to make the most of what was available. This is why children have a natural aversion or “distaste” for “new” foods and only increase the scope of what they will eat as they mature. Remember when you wouldn’t eat x – fill in the blank. For me, it was Brussels sprouts, which today I love, especially tossed in olive oil and roasted.
Then, as we became more “civilized” and gathered together for socialization and protection, we wandered about less. This undoubtedly fostered the beginnings of agriculture. We saw that cereal grains, that is, the seed heads of grasses such as corn, wheat, and rice, grew naturally where nature planted them. We reasoned, why wander about when we could plant our food supply and water and cultivate and harvest it where we lived? This also enabled us to build more permanent shelters and live in fertile places with good fresh water supplies and abundant game and vegetative life. We also learned that we could catch certain animals and domesticate them for a steady food supply as they multiplied naturally in captivity. Wunderbar! Surely, this was a milestone of human evolution.
Could life get any better? Perhaps. But, in the view of many students of these developments, this was also the beginning of mankind’s downfall, nutritionally speaking. It was the dawn of the onset of the age that was to bring us the dreaded Diseases of Civilization. It was the advent of the Neolithic Age, and it began about 10,000 years ago.
Fast forward to about 150 years ago. William Banting¹, in 1863 a retired London undertaker, wrote and published a 16-page pamphlet titled Letter on Corpulence – Addressed to the Public. In it, the 5-foot 5-inch, 200-pound Banting – surely a fat man – described a program of eating in which he “scrupulously avoided eating any…food that might contain either sugar or starch.” On Banting’s diet, he ate 5 or 6 ounces of meat or fish at each of three meals every day, together with a fair amount of wine and spirits, avoiding altogether “bread, milk, beer, sweets and potatoes.”  Banting lost about 50 pounds in 18 months. His pamphlet became a best seller in England and on the Continent.
William Banting credited his diet to William Harvey, an aural surgeon in London who had recently been to Paris where he had heard the great French physiologist Claude Bernard debate on diabetes. Voila! So, there you have it.
Now, fast forward again to about 50 years ago, to include the impact of the Industrial Revolution, the new roller-milling technology for making flour, trans-fat-loaded Crisco and “vegetable” oils made from soy beans and corn.  
On January 13, 1961, Ancel Keys, an assertive University of Minnesota physiologist (after whom WWII’s K-Rations were named), was on the cover of Time Magazine. Since the 30’s Keys had been interested in the influence of diet on health. His epidemiological work on the etiology of heart disease would later be published in his 2nd seminal tract, the “Seven Countries Study” (Harvard University Press, 1980). In it he advanced his hypothesis associating saturated fat and dietary cholesterol with heart disease. This was the genesis of the Diet-Heart (Lipid) Hypothesis.
Keys’ Lipid hypothesis led the nation and the world to the Low-Fat diet. Lamentably, the study was later discovered to have been “cherry picked.” It will be the subject of the third essay of this series, but first will be a primer for non-scientists (and physicians) on “The Basics of Nutrition: Macronutrients, Vitamins, Minerals and Phytochemicals.”
¹ “Prologue: A Brief History of Banting” from Gary Taubes’ Good Calories – Bad Calories, 2007, Alfred A. Knopf

No comments:

Post a Comment