Caveman cook calorie kerfuffle corrected

Despite our preoccupation with all things gastronomic, surprising little is known about how food preparation affects the energy it supplies to our bodies. Now, for the first time, Harvard researchers have shown that cooked food yields more energy than raw, leading them to speculate that cooking played a key role in driving the evolution of modern humans.

“It is astonishing that we don’t understand the fundamental properties of the food we eat,” observed researcher Rachel Carmody. “All the effort we put into cooking food and presenting it – mashing it up, or cutting it, or slicing or pounding it – we don’t understand what effect that has on the energy we extract from food, and energy is the primary reason we eat in the first place.”

Carmody’s study, appearing in the Proceedings of the National Academy of Sciences, shows that cooked meat provides more energy than raw meat, suggesting that humans are biologically adapted to take advantage of the benefits of cooking, and that cooking played a key role in driving the evolution of man.

Although earlier studies have examined specific aspects of what happens during the cooking process, this is the first study to assess whether cooking affected the in vivoenergy value of food. “There had been no research that looked at the net effects – we had pieces that we could not integrate together, so we didn’t know what the overall answer was,” Carmody said.

Her experiment involved feeding two groups of mice a series of diets that consisted of either meat or sweet potatoes prepared in four ways – raw and whole, raw and pounded, cooked and whole, and cooked and pounded. Over the course of each diet, the researchers tracked changes in each mouse’s body mass, as well as how much they used an exercise wheel. The results, Carmody says, clearly show that cooked meat delivers more energy.

Although early humans were eating meat several million years ago, without the ability to control fire, any meat in their diet was raw, and probably pounded using primitive stone tools. Approximately 1.9 million years ago, however, a sudden change occurred. The bodies of early humans grew larger. Their brains increased in size and complexity and adaptations for long-distance running appeared.

Previously, this increase in brain size had been linked to a seafood diet rich in iodine. Carmody’s research points to another possible hypothesis – that cooking provided early humans with more energy, allowing for such energetically-costly evolutionary changes.

Interestingly, the impacts of the new findings aren’t limited to the early days of human evolution. They also lay bare the shortcomings in the Atwater system, the calorie-measurement tool used to produce modern food labels. “That system is based on principles that don’t reflect the in vivo energy availability,” Carmody explained. “Although it measures what has been digested, the human gastrointestinal system includes a whole host of bacteria, and those bacteria metabolize some of our food for their own benefit. Atwater doesn’t discriminate between food that is digested by the human or the bacteria, and increasing evidence suggests that the bacteria take a pretty good portion of the food we eat. In fact, research has shown that one of the ways to increase the value humans get, relative to the bacteria, is by processing food, and cooking is one way to do that.”

The research could also inform how food scientists tackle one of the, er, biggest dietary challenges – the prevalence of obesity in Western nations, and malnutrition in developing parts of the world. “As human evolutionary biologists, we think about energetic gain as being something positive, because it allows for growth and reproduction, and it’s a critical component of a species’ evolutionary fitness,” Carmody said. “But the question in the modern world is: If we now have the problem of excess as opposed to deficit, is that still a positive?”

Related:
Discuss this article in our forum
Processed food cripples young brain
Food, Notorious Food
Evergreen agriculture emerges as Africa’s key to food security
BPA levels in US foods assessed for first time

Source: Harvard University

, , , ,

Comments are closed.

Kitchen Timer Digital Large Magnet Cooking LCD Alarm Loud Count Down Clear 99min picture

Kitchen Timer Digital Large Magnet Cooking LCD Alarm Loud Count Down Clear 99min

$5.39



HOMITT Kitchen Butane Torch Refillable for Culinary Cooking BBQ Torch Lighter picture

HOMITT Kitchen Butane Torch Refillable for Culinary Cooking BBQ Torch Lighter

$15.80



Refillable Kitchen Torch Lighter Blow Torch Safety Lock Rotating Angles Flame picture

Refillable Kitchen Torch Lighter Blow Torch Safety Lock Rotating Angles Flame

$12.99



Butane Blow Torch Lighter Culinary Torch Chef Professional Cooking Torches picture

Butane Blow Torch Lighter Culinary Torch Chef Professional Cooking Torches

$12.98



Blow Torch Butane Jet Flame Lighter Refillable Cooking Kitchen BBQ Windproof picture

Blow Torch Butane Jet Flame Lighter Refillable Cooking Kitchen BBQ Windproof

$9.89



Refillable Butane Torch Lighter Adjustable Cigar Lighter 2 Jet Flame Lighter picture

Refillable Butane Torch Lighter Adjustable Cigar Lighter 2 Jet Flame Lighter

$12.99



New US Military 1 Qt. Canteen Cup Cooking Stand Stove Heater Aluminum picture

New US Military 1 Qt. Canteen Cup Cooking Stand Stove Heater Aluminum

$14.99



12 pcs Silicone Kitchen Utensil Cooking Shovel Wooden Handle Cooking Set Black picture

12 pcs Silicone Kitchen Utensil Cooking Shovel Wooden Handle Cooking Set Black

$8.89



2 PACK Refillable Lighter Adjustable Torch Lighter for Cooking BBQ Double Flame picture

2 PACK Refillable Lighter Adjustable Torch Lighter for Cooking BBQ Double Flame

$16.99



Pre-Seasoned 12.5 Inch Cast Iron Skillet Multipurpose Use by Utopia Kitchen picture

Pre-Seasoned 12.5 Inch Cast Iron Skillet Multipurpose Use by Utopia Kitchen

$26.98



Powered by WordPress. Designed by WooThemes