Scientists pinpoint the origins of humanity's love of carbs
CTV
The origin of modern humans' long-standing love affair with carbs may predate our existence as a species, according to a new study.
The origin of modern humans’ long-standing love affair with carbs may predate our existence as a species, according to a new study.
A once prevailing stereotype of ancient humans feasting on mammoth steak and other hunks of meat helped foster the idea of a protein-heavy diet that was necessary to fuel the development of a large brain.
But archaeological evidence in recent years has challenged this view, suggesting that humans long ago developed a taste for carbohydrates, roasting things such as tubers and other starch-laden foods that have been detected by analyzing bacteria lodged in teeth.
The new research, published in the journal Science on Thursday, offers the first hereditary evidence for early carb-laden diets. Scientists traced the evolution of a gene that enables humans to digest starch more easily by breaking it down into simple sugars that our bodies can use for energy. The study revealed these genes duplicated long before the advent of agriculture.
This expansion may even go back hundreds of thousands of years, long before our species, Homo sapiens, or even Neanderthals emerged as distinct human lineages.
Researchers based at The Jackson Laboratory in Farmington, Connecticut, and the University of Buffalo in New York state analyzed the genomes of 68 ancient humans. The study team focused on a gene called AMY1, which allows humans to identify and begin breaking down complex carbohydrate starch in the mouth by producing the enzyme amylase. Without amylase, humans would not be able to digest foods such as potatoes, pasta, rice or bread.
Humans today have multiple copies of this gene, and the number varies from person to person. However, it has been tricky for geneticists to piece together how and when the number of these genes expanded — a reflection of when eating starch likely became advantageous for human health.
