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KarenJ
Thu, Feb-14-08, 19:50
Genes that conquered cold blamed for fat (http://news.yahoo.com/s/nm/20080215/ts_nm/genes_metabolism_dc_3)



By Julie Steenhuysen1 hour, 15 minutes ago

Genes that helped early humans adapt to cold climates may be driving metabolism-related diseases such as obesity or diabetes in many countries, U.S. researchers said on Thursday.

They found a strong correlation between climate and genetic adaptations that influence the risk of metabolic syndrome, a group of related disorders such as obesity, high cholesterol, heart disease and diabetes.

"Climate over a long period of time has shaped the distribution of genetic variants that may be associated with the risk of these common metabolic disorders," said Anna Di Rienzo, a professor of human genetics at the University of Chicago.

Anthropologists have long made the case that certain traits such as differences in skin pigmentation reflect early human migration from equatorial Africa to cooler climates -- for instance, the link between paler skin and an ability to synthesize vitamin D from sunlight.

"There are all of these traits, body mass or skin pigmentation, that we know are strongly correlated with environmental variables," Di Rienzo said in a telephone interview.

Di Rienzo and colleagues wanted to see if genes that were once useful for tolerating cold climates were playing a role in diseases of the metabolism.

"To survive in these climates, they had to adapt," said Di Rienzo, whose study appears in PLoS Genetics, a journal published by the Public Library of Science. (http://genetics.plosjournals.org/perlserv/?request=get-document &doi=10.1371/journal.pgen.0040032).

ENERGY BOOSTER

"They had to develop genetic variants that made them more efficient in terms of energy metabolism and that made them more able to cope with cold climates by increasing their rate of thermogenesis -- the ability to generate and maintain heat," she said.

The research team picked 82 genes associated with energy metabolism and looked to see if there were any correlations with climate. They studied variations in 1,034 people from 54 populations.

They saw several clusters of different genetic variations related to metabolic syndrome in colder climates.

One gene, the leptin receptor, is increasingly common in areas with colder winters. Leptin is important to appetite and weight gain -- something people need no help with in modern times.

"We eat a lot more, we don't exercise nearly as much as our ancestors used to do, and these adaptations that made us cope well to a cold climate now make us prone to a number of metabolic disorders," Di Rienzo said.

She said the study sheds light on why some of these variants are more common in certain populations. "It helps explain the evolutionary origins of these diseases," she said.

(Editing by Maggie Fox and Xavier Briand)

Copyright © 2008 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon.
Copyright © 2008 Yahoo! Inc. All Rights Reserved. Privacy Policy | Terms of Service | Send Feedback | Help

By Julie Steenhuysen1 hour, 15 minutes ago

Genes that helped early humans adapt to cold climates may be driving metabolism-related diseases such as obesity or diabetes in many countries, U.S. researchers said on Thursday.

They found a strong correlation between climate and genetic adaptations that influence the risk of metabolic syndrome, a group of related disorders such as obesity, high cholesterol, heart disease and diabetes.

"Climate over a long period of time has shaped the distribution of genetic variants that may be associated with the risk of these common metabolic disorders," said Anna Di Rienzo, a professor of human genetics at the University of Chicago.

Anthropologists have long made the case that certain traits such as differences in skin pigmentation reflect early human migration from equatorial Africa to cooler climates -- for instance, the link between paler skin and an ability to synthesize vitamin D from sunlight.

"There are all of these traits, body mass or skin pigmentation, that we know are strongly correlated with environmental variables," Di Rienzo said in a telephone interview.

Di Rienzo and colleagues wanted to see if genes that were once useful for tolerating cold climates were playing a role in diseases of the metabolism.

"To survive in these climates, they had to adapt," said Di Rienzo, whose study appears in PLoS Genetics, a journal published by the Public Library of Science. (http://genetics.plosjournals.org/perlserv/?request=get-document &doi=10.1371/journal.pgen.0040032).

ENERGY BOOSTER

"They had to develop genetic variants that made them more efficient in terms of energy metabolism and that made them more able to cope with cold climates by increasing their rate of thermogenesis -- the ability to generate and maintain heat," she said.

The research team picked 82 genes associated with energy metabolism and looked to see if there were any correlations with climate. They studied variations in 1,034 people from 54 populations.

They saw several clusters of different genetic variations related to metabolic syndrome in colder climates.

One gene, the leptin receptor, is increasingly common in areas with colder winters. Leptin is important to appetite and weight gain -- something people need no help with in modern times.

"We eat a lot more, we don't exercise nearly as much as our ancestors used to do, and these adaptations that made us cope well to a cold climate now make us prone to a number of metabolic disorders," Di Rienzo said.

She said the study sheds light on why some of these variants are more common in certain populations. "It helps explain the evolutionary origins of these diseases," she said.

(Editing by Maggie Fox and Xavier Briand)

Copyright © 2008 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon.
Copyright © 2008 Yahoo! Inc. All Rights Reserved. Privacy Policy | Terms of Service | Send Feedback | Help

"We eat a lot more, we don't exercise nearly as much as our ancestors used to do, and these adaptations that made us cope well to a cold climate now make us prone to a number of metabolic disorders," Di Rienzo said.

I'm not sure if I agree with that. Did our ancestors really exercise that much?

respira
Thu, Feb-14-08, 20:02
I'm not sure if I agree with that. Did our ancestors really exercise that much?

Well, If I had to do the laundry by hand instead of in a washing machine it would do me in. And that's just one chore. I am very glad I was born after they invented washing machine.

Interesting article, Thanks

Zei
Sat, Feb-16-08, 16:22
Not just washing clothes, but growing, shooting or gathering what they're made of and making it, growing, shooting or gathering food, firewood, building your own shelter...even the lifestyle my mom describes from say 70 years back required a lot more effort than now.

mike_d
Sat, Feb-16-08, 16:44
As fit as I am now, I doubt I could plow with some oxen a patch of field in a days time, clear a wooded field with hand tools or build a log cabin.

I know in Winter I have more appetite-- if I eat too many carbs in a day I awake sweating in the middle of the night.

pennink
Sat, Feb-16-08, 17:05
making clothes, heck making bread!!! dying fabrics...

oh, and if anyone of you has ever carded wool you'd never doubt that they exercised. (you take two paddles, on their right side they have little spikes, similar to giant velcro spikes and equally as 'sticky', you put a piece of washed raw wool between the paddles -- then smack down and pull through over and over... the pecks you get will rival anything the bowflex could imagine!)

(I used to work in a museum/re-creation of the 1800s)

if life, only 150 years ago was that hard... can you imagine before?

KarenJ
Sun, Feb-17-08, 10:02
I would agree that our ancestors worked hard, but that's only been the case for a few thousand years. Think of it in terms of two million years, and a different scenario appears. We didn't need washing machines because we didn't have laundry, because we didn't make our own clothing. The clothing was supplied by the animals we ate.

Dr. Kerin O'Dea (http://www.aihw.gov.au/eventsdiary/ah04/speakers_kerin_odea.cfm) showed that Australian urban aborigines who were returned to their original way of life (Hunter Gatherer) actually became less active.

ElleH
Sun, Feb-17-08, 12:21
It's a very physical process, slaughtering and cleaning a large animal took probably hours, just to prepare it to be cooked.

TBoneMitch
Sun, Feb-17-08, 22:00
Youre right Elle, but on average hunter/gatherer men hunted 1-3 times per week, while the women gathered.

And of course, the larger the kill, the more work it takes to butcher/skin/bring back to camp. So you have very intense physical activity there.

But you dont do such a hunt every day because there is usually some left overs for a couple of days. And the larger the kill, the more left overs.

So there was still plenty of idle times compared to early agriculturalists who worked all day, every day, plowing fields, treshing and harvesting.

Arthur Devany talks a lot about the activity patterns of hunter/gatherers vs that of agriculturalists.

It seems that hunters/gatherers did relatively infrequent and relatively short super intense work, while agriculturalists did a high amount of daily grinding low-to-moderate intensity work.

And of course, the health of hunter/gatherers was far better than that of early agriculturalists.

I think it has relevance to the optimal activity levels of modern human beings.

I like to workout 2-3 times a week in a high intensity style, for around 30 minutes.

I leave the high volume work to the cardio junkies and bodybuilders!

kneebrace
Sun, Feb-17-08, 22:17
I would agree that our ancestors worked hard, but that's only been the case for a few thousand years. Think of it in terms of two million years, and a different scenario appears. We didn't need washing machines because we didn't have laundry, because we didn't make our own clothing. The clothing was supplied by the animals we ate.

Dr. Kerin O'Dea (http://www.aihw.gov.au/eventsdiary/ah04/speakers_kerin_odea.cfm) showed that Australian urban aborigines who were returned to their original way of life (Hunter Gatherer) actually became less active.

Got a reference Karen ?. It sounds like nonsense. I've spent a lot of time with both, and believe me, sitting on a couch watching TV with a fridge in the next room is a lot less work than hunting and gathering. Most of the gathering that Australian Aboriginal women do involves digging, which is very hard physical work. You also have to remember that if you weren't carrying the fruits of your digging/tools thereof, you usually were carrying an infant. Even 'ceremony' (the recreation sports like dancing) were very physical.

Traditionally living Aborigines are very active. And that's even with the use of guns. The ones who had no use of modern technology (metals etc.) would have worked incalculably harder.

Stuart

KarenJ
Mon, Feb-18-08, 10:34
Got a reference Karen ?.

Stuart

No. If anyone has the bibliography of the original Protein Power, it would be in there.

Early humans did not hunt. They were scavengers and ate their meat raw.

kneebrace
Mon, Feb-18-08, 16:07
Quote:
Originally Posted by kneebrace
Got a reference Karen ?.

Stuart

No. If anyone has the bibliography of the original Protein Power, it would be in there.


Early humans did not hunt. They were scavengers and ate their meat raw.

Well, my curiosity was sufficiently piqued by such twaddle that I rang Kerin O'dea up to check what she actually thought, because I am aware she is very well qualified in indigenous health. Apparently she never even suggested anything of the sort. If she is so quoted in PP it is inaccurate. It did sound pretty unlikely.

And AFAIK, early humans did both. No disagreement on the raw consumption though. But even scavenging is hard work. You have to find your carrion first, all on foot, with the weapons and training (through 'play' with your peers) to fight off other predators /scavengers/competing tribes of your own kind, then you have to butcher the carrion with only rudimentary tools and do the fight thing all over again. Believe me, it was no leisurely process.

Modern humans have an understandably naive view of how physically strenuous paleo life would have been.

Stuart