FYI: Will People Ever Evolve Out of Craving Unhealthy Food?

By Amber Williams Posted 02.20.2012 at 5:01 pm 7 Comments

Donuts Food cravings may be triggered by a drop in blood sugar, which can lead to a drop in self-control. Obesity can heighten cravings. Christopher Stevenson/Getty Images

Maybe, but it’s going to take a long time. For the past 200,000 years or so, fatty and sugary foods were hard for humans to come by and well worth gorging on. Fats help maintain body temperature, sugars provide energy, and craving such food is hardwired: Eating fats and sugars activates reward centers in the brain.

Scientists are finding that the degree to which we experience those cravings can also be influenced by genes. Obesity runs in families, and although scientists still don’t know just how much of craving is hereditary and how much is learned, they have located more than 100 genes that seem to be linked to the disease. To evolve out of cravings, we’d need to stop passing down these genes.

Rob DeSalle, an evolutionary biologist at the American Museum of Natural History in New York, says that could take a while. The health conditions associated with a poor diet mostly affect middle-aged adults, who have probably already had children and passed their genes on. Perhaps, he speculates, if more children and teens get obesity-related ailments, such as heart disease and Type II diabetes, fewer will survive to reproduce, stripping craving-related genes from populations more quickly. Even then, weeding out all 100 genes is unlikely. Also, genes associated with obesity aren’t killers. They don’t code for sickle-cell anemia or cystic fibrosis. If those bad genes have hung on for a very long time, DeSalle says, marginally bad ones could hang on even longer.

Evolution is a messy process that plays out over millions of years. It typically lags far behind changes in species behavior. Until about 50 years ago, craving fats and sugars actually helped us survive. Then fast food became abundant, and the number of obese people in the U.S. tripled between 1960 and 2007. Half a century is “just not enough time to counteract millennia,” says Katie Hinde, a human evolutionary biologist at Harvard University.

Even someone genetically predisposed to crave food doesn’t have to end up fat. “Your genes are not your destiny,” DeSalle says. Take, as an extreme example, people with phenylketonuria, a recessive metabolic disorder in which a person is unable to break down phenylalanine, an amino acid, and risks mental retardation if he ingests it. By avoiding certain foods (eggs, nuts), he’ll be fine.

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7 Comments

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boka

02/20/12 at 5:30 pm

Chocolate covered bacon.

"I contend that we are both atheists. I just believe in one fewer god than you do. When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours"

- Stephen Roberts

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Robot

02/21/12 at 9:35 am

We have 250 genes the scientists do not know where they came from. They just exist suddenly in the evolution of humans suddenly for no reason for their appearance.

The aliens that tweak with the monkeys to make intelligent slaves of us put those genes there as well suppress 75% the rest of our genes. So I imagine somewhere in the process we go the jelly donut, chocolate croissant gene from our alien overlords. It could have come from Zeus or his brother Poseidon. Both of them tweak around with the monkey genes. Zeus made 75% of the humans on planet earth and Poseidon made the other 25%. The 25% is negative RH.

Biblically both Poseidon and the devil carry the exact same pitch fork.

It is interesting to note that Zues and Poseidon are brothers, which implies a family above them, parents. The battle between these 2 bothers continues in outerspace and on earth.

Posdeidon was cast down to earth with followers of 33%.

Humans were made to serve and praise god and not ask questions. Hence do not eat from the tree of knowledge. Seems Posideidon tempted Eve with fruit.

Before Eve was Lilith. Lilith was created POOF exactly from nothing in the same manner as Adam. Infact Adam watch Lilith being made in the process and kind of grossed out from watching the whole process. After the process of Lilith was done and the two of them has sexual relations, Lilith just enjoy sex as much as Adam and want to be as amorous as Adam. When Lilith desire to be ontop, Adam would not conform and banish Lilith from him. Biblically, I find this hard to see as a sin in life? She was just felt equal to Adam too and this was aother social problem between the two. Again, being equal I find it hard to see as a sin in life? The whole thing of banishing Lilith does not make sense to me.

Do not worry, the aliens are still with us and tweaking with our genes too. One day they will make their appearance known to all of us. Maybe this is the year and relates to December 21, 2012, maybe.....

.............................
Science sees no further than what it can sense.
Religion sees beyond the senses.

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hollycow

02/21/12 at 10:33 am

In one sentence the author says fatty sugary foods are both good and bad for you. Which is it? With all the false information we receive every day no one knows for sure. Most of this information is designed to sell us something rather that tell us the truth.

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Porphy

02/21/12 at 11:23 am

So eat and exercise like a caveman. Got it.

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LionFox

02/21/12 at 11:44 am

This website would actually be enjoyable if not for the idiots and the nutjobs.

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Aldrons Last Hope

02/21/12 at 2:14 pm

Actually science is showing us that obesity is increasing across all G-20 nations because of chemical interactions between plastics and our biology. These chemicals are programming us to be fat regardless of what we eat. Check out the link.

http://www.davidsuzuki.org/blogs/panther-lounge/2012/01/is-pollution-making-us-fat/

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Robot

02/21/12 at 4:47 pm

Aldrons Last Hope,
Nice to see you and not the imposter ALH.

I agree with you completely that all animals in our environment, especially us humans are being negatively affected by thousands of different manmade chemicals of estrogens with another culprit on the side sugar, hydrogenated fats and just eating to many high carbs. But I believe the article is asking why we humans are genetically addicted to these high carbs?

Yes it could be a self inflicted environment factor we humans impose on ourselves and something the annunaki did not have in mind, when they originally tweaked with our genes.

............................
Science sees no further than what it can sense.
Religion sees beyond the senses.

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