May 8, 2016


This is what life would actually be like without processed food (Roberto A. Ferdman, May 7, 2016, Washington Post)

To understand what life would be like without any processed food, you would have to go back more than 3 million years, not merely a few decades. And you have to understand the effect of the very first form of food processing: cutting.

This might sound ridiculous, but bear with me, because it's the most primitive form of food processing (cooking, which substantially alters the composition of food, is a significant form of processing, too) and it has changed our lives in ways few people, if any, appreciate.

"If we were to go back to the very beginning of this process that has gone to an extreme today, I think it would really surprise many people," said Daniel Lieberman, a professor of biological sciences at Harvard University. "We used to spend a disproportionate amount of our days chewing."

"You can go for an entire day without chewing today, and that's really bizarre from a historical standpoint," he added.

Lieberman pointed to the eating habits of chimpanzees, who spend about half their day chewing, for perspective. That might sound ridiculous, but it's not as far off from how we used to eat than one might think. Our teeth, he said, just aren't capable of breaking certain foods down efficiently without any form of extra-oral food processing (a fancy term for any and all changes food undergoes before it enters our mouths).

The clearest example is our capacity to break down meat, which Lieberman, along with Katherine Zink, who teaches at the department of human evolutionary biology at Harvard, tested as part of a new study. The researchers had a group of participants chew samples of both meat (goat, in this case) and vegetables (jewel yams, carrots and beets) in various states of processing -- roasted, pounded, sliced and unprocessed (i.e. untouched). And what stood out is how poorly we're able to break down raw meat, even though people have been carnivores for more than 2.5 million years. That is, until they sliced it into smaller bits. [...]

"If I were to give you a piece of goat that's raw, it would be like chewing bubble gum," Lieberman said. "You can't break it down."

But something as simple as cutting it into smaller bits, the first of what has become an endless list of ways in which we change edible things before ingesting them, makes an enormous difference. The process didn't exist until the development of stone tools, but marked the beginning of a long and winding road toward where we are today, when chewing our food is more an afterthought than a several hours affair. 

Posted by at May 8, 2016 12:51 AM