Can People be Addicted to Food?
A batch of articles have been in the press, citing a study out of Yale about food addiction. It was conducted by Ashley Gearhardt and Kelly Brownell. Of course as with a lot of popular reporting on science, finding a real reference to the article was hard to find. Here is where I found the first link to the actual article:
http://www.washingtonpost.com/blogs/the-checkup/post/yale-study-probes-food-addiction/2011/04/04/AFnXMggC_blog.html
If you want to read lots of articles about it, go to google news and search for food addiction.
It was published by the Archives of General Psychology, http://archpsyc.ama-assn.org/
A lot of the quotes in the popular articles are people not seeming to be surprised, and one common thread I see in the articles is the thought that:
Food addiction is like drug addiction.
I think this is backwards. It is interesting that our bodies can become addicted to drugs. That the body can take in a substance and change it’s functioning or homeostasis to the point where the normal state is having the drug in the system. It then sees the state of not having the drug as abnormal and takes measures to correct this. It induces a craving so that the organism will go out and correct the abnormal state.
How did this system come about? If you think evolutionarily, why would this happen? How would having such strong cravings for something that is causes the organism to go out and engage in possibly dangerous behaviors help in the long run. Maybe if it was something needed for life, like maybe food??? or water??? I think that the more accurate statement would be:
Drug addiction is like the need for food.
The drug addiction takes an evolutionary adaptation to eat when hungry, and to go out and perform a possibly dangerous task (hunting) to obtain food. In the short run, you could die today from hunting, but you will live for weeks or longer without food, so the body needs a way to motivate you to seek food. It does this by rewarding you when you eat. It increases the reward of eating (and drinking, and sex- reproduction is very important in evolution) to the point where it is worth it to sustain some danger and discomfort to get it, and it gives the body a craving for the substance that brings the reward.
It is drugs that hijack this system from food, not food that uses the addiction axis.
How did this system come about?
ReplyDeleteBasically our body produces pleasure chemicals i.e. opiods etc., as a matter of course. So when similar are ingested our feedback mechanisms respond by dampening down that internal production.
The swiftness, severity and above all intractability of that response forms the basis of chemical addiction, as you described.
You are right, they've got it backwards, drug addiction is sometimes a bit like eating/food, not the other way around, when it becomes (or feels like) a necessity, such as eating actually is.
It makes no sense to compare an essential need (eating), to a pathology, unless you see that necessity as pathological and/or wish to further pathologize it.