Diet Science

The Summer, 2015 issue of Scientific American magazine has an engaging article called, “The Birth of the Modern Diet.”  In it, the author, Rachel Laudan, tells us how opinions about food have changed over the centuries based on what scientists believe about the human body.

In 1547, Andrew Boorde said, “A good coke is halfe a physysyon.”  Translated, it means that a good doctor would be a good cook and able to translate dietary theory into dishes for the King.  That theory dated back to Hippocrates in 400 B.C.  The body was believed to be comprised of four fluids or humors:  Blood, phlegm, yellow bile, and black bile.  The fluids were further labeled according to their temperature and “moisture,” blood being hot and moist for instance, and black bile cold and dry.

In this theory, a healthy person was slightly warm and slightly moist and ideally should be fed food that is slightly warm and slightly moist.  Blancmange was therefore a perfect food.  Blancmange was a dish made of chicken, rice, and almond milk with a little sugar to top it off – warm and moist.  Notably, in this theory, root vegetables were thought to be dry and cold and were best left to the peasants.

In the middle 1600’s, new ideas began to brew.  The technology of distillation allowed chemists to focus on fermentation, and to study the way food was changed as it was digested.  Resulting deductions were that foods fell into three categories:  foods that provided pleasant smells when mixed with other foods (wine and meat), foods that offered binding qualities (butter), and foods that improved the taste of other foods (salt and flour).  “Healthy” foods were those which fermented easily and provided good smells, binding qualities, and flavor.  Enter champagne, sauces, Roux, salads, fruits, herbs, vegetables, meat, fish, and bouillon. French food became the beloved ideal.

During this time of research, a British physician noticed the sugary urine in patients suffering from diabetes, and declared sugar to be dangerous.  Now, rather than sprinkled on main dishes, sugar was served only after a meal, as dessert.  These food theories were adopted across Europe, England, Canada, and Australia. 

In the 1900’s, the focus of food in the US began to shift away from how to feed the rich and on to ways to provide cheap, but adequate, meals for factory workers, government project workers,  sailors, and soldiers.  It was discovered in laboratories that foods consisted of calories, carbohydrates, fats, proteins, vitamins, and minerals.  Science wanted to solve the problems of deficiencies such as iron deficiency and scurvy.

Now that we’ve succeeded in getting ample food to most Americans, we are faced with a whole new challenge – how to eat less.  How do we avoid overeating at dinner?  How do we stop a soda habit or “ice cream at bedtime” habit?  As a species, we were wired to over eat caloric-rich food to balance times of famine.  In a time of prolonged abundance, new survival skills are needed that guide us to new territory – portion control.

Landau, Rachel. “The Birth of the Modern Diet.” Scientific American. Summer 2015: 64-71.