Posted by: lemonator | December 11, 2008

Sugar ‘addiction’?

Lemonator here.

 

I’d like to introduce a semi-regular new feature of this blog, in which I go about debunking some foolish scientific claim relating to food.  As a scientist myself, it makes me cringe when the pop media grabs ahold of a scientific finding and distorts it for sensationalistic purposes… I especially find it worrisome when the research underlying it has some rather… major holes.

The first example is unrelated to food, but got me more incensed than any other thing I’ve read in the past year or so.

NYT article on mood disorders

So, a bit of background:  Imprinting is a genetic effect in which certain genes are turned on only on the chromosome you got from your mother, and other genes are only turned on on the chromosome you got from your father.  There are several theories for why this came about (all other genes are turned on in either both or neither chromosome), but a prevailing theory is that maternal genes (from the mother) act to somehow improve the mother’s chance of surviving pregnancy and childbirth, while the paternal genes (from the father), not needing to worry about their own survival, act instead to promote the survival of the baby at all costs.  A good example, referenced in the article, is IGF2.  IGF2 promotes growth of the fetus during pregnancy.  This is great for the father… large babies survive better, and his genes want to survive!  This is less good for the mother… it takes more resources to make a bigger baby, and birth is much more difficult.  So, as might be expected, the mother’s copy of the gene is turned off in the child, while the father’s is on.

This is all fine and good.  But then the researchers whom the article is talking about overstep the bounds of science and go into random-theory-generation-land.  They suggest that all mood disorders ultimately lie on a spectrum, with autism on one end and schizophrenia on the other, with things like depression, etc in the middle.  This assertion is already on some rather shaky ground… in order to put the disorders onto a spectrum like this, you need to creatively interpret some of the symptoms (ex.  Autism is all about object-focused behavior while schizophrenia is all about self-focused behavior(??)).  It gets even more shaky when they attempt to apply imprinting to it… they posit that there are genes (unknown genes) under control of imprinting (okay…) which are at war with one another to determine the mood of the individual (bwah?).  Well, aside from the fact that 1)  that’s not how imprinting works (the genes aren’t actively repressing one another) and 2) The other plausible explanation, that somehow in certain individuals all paternal genes are more highly expressed than in others, has no scientific evidence of such a master regulator and would lead to many phenotypic (visible) effects on the individual far beyond driving them towards a mental disorder, the logic of which genes are imprinted for whom and what they do is… baffling.

Paternal genes lead to a fascination with objects, patterns and mechanical systems.

Maternal genes lead to a hypersensitivity to their emotions and the emotions of others

Anyone notice something interesting there?  How, without any documentable proof (I looked at their original article… no proof there either), they suggest that the paternal genes lead to stereotypical ‘male’ behaviors, while maternal genes lead to the stereotypical ‘female’ behavior of caring about how others feel.  I about hit the roof at this point… this article, and the researchers, are being irresponsible to make a claim like this with no actual scientific proof to back up their claim.  Of course, in the letters to the editor for this article, there are many people who are saying that ‘they’ve known all along that there were differences between men and women (not what imprinting does, but from this article simple enough to misinterpret)’  Its a shame when inadequate explanation and a desire to sensationalize promotes stereotypes.

 

Okay, done with that one.  Onto the article about food:

MSN health article on Sugar addiction

In this article, the author suggests that a recent study states that sugar is as addictive as cocaine and heroin, and can be a ‘gateway’ to other drugs, such as alcohol.  That’s right parents!  Keep your kids away from the soda or they’ll become alcoholics when they grow up!  This is sensationalism at its finest, and, as can be expected, the science to back it up is quite dubious.  The science involved is a study of the brains of rats fed sugar water (effectively soda).  The article says that the rats binged on the soda, and that the soda released a surge of dopamine (the same stuff that is generated from cocaine!!!!!!!!!!!!) into the brain and activated the pleasure sensor.  When the soda was taken away, the rats went into withdrawal and were very unhappy.

Wow, you say… that sounds like addiction to me!  Well… not so much, and mostly because of the way that they went about actually *doing* the experiment.  They deprived the rats in the study of any food or water for twelve hours, then gave them soda, then deprived them of all food and water for another twelve hours, etc, etc, for three weeks.  Now, I’m sorry, but if I’ve been deprived of food for twelve hours (and rats eat more frequently than humans) and someone handed me a soda… I’d be very happy to drink it.  My brain would register immense pleasure at the taste and calorieness of the soda. (there’s the dopamine!).  Then, if I didnÂ’t get any more food for twelve more hours, then was handed another soda, you’d bet I’d want it again.  I’d also realize that between my sodas, I had to go hungry for twelve hours, and sugars leave your system pretty fast, so I’d get hungry quickly… now, that could make anyone unhappy and withdrawal-y.

So, if anyone tells you that sugar is ‘addictive’… they’re being creative with their words… unless better evidence comes out… I’m not at all convinced by something as pop-sci as this latest article jumping on the ‘sugar is bad, oh noes!’ bandwagon.  Does sugar perhaps prime your system for other quick carbohydrate sources?  Possibly.  Might it lead to overindulgence?  well, yes.  But is it addiction?  Not that I can see.

 

Well, there’s the first entry in this series… I need a name for it, though.  Any suggestions?  Food-Science-Article-Debunking seems… too long.

Advertisements

Responses

  1. I LOVE this.
    My name ideas seem long too:
    Debunking Pseudoscientific Claims?
    Thinking Critically About Research?
    Good Headlines Doesn’t Equal Good Science?
    Check Yo Methods
    LOL!

  2. ha, this is great. how about “That’s not science”

    food studies are hard, i don’t believe much of what i’ve heard… too much that can’t be controlled! and people themselves are so different, then factor in activity levels, age, genes… jeepers!

  3. Haha!! Yeah, it doesn’t sound like an addiction to me either.

  4. Wow, interesting post! It is actually very insightful.

  5. ‘That’s not science’ is great!

    Look for more coming soon!

  6. Neat idea!

    As for the sugar addiction, I think this article does go a bit far, but I know that when I stop eating sugar for a while and then eat it again suddenly I’m craving it all the time. So I do definitely think that sugar is addictive.

  7. […] modifications to the promoter regions that regulate when the gene is active and not (check my first THATS NOT SCIENCE for a talk about […]


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Categories

%d bloggers like this: