Friday, July 15, 2016

Why We Binge Eat (maybe)

I've been chubby my entire life. I once dated a fairly slim woman whose mother was equally slim. One day, while talking about pie, she (the mother) wondered why anybody ever overeats pie - she asked, "why don't you just have a single piece of pie, then stop?" She legitimately didn't understand. Don't worry, I resisted the urge to punch her. It was hard.

Not everyone who trains in martial arts needs to lose bodyfat, and not everyone who needs to lose bodyfat has a problem with binge eating, but I suspect that a significant number of us belong to both groups. I personally have had problems with binge eating for my entire life. I'm the type of person who usually consumes fewer than 3,000 kcal/day, but I can easily scarf down 2,000 + kcal in a single sitting and still find myself tearing through the refrigerator looking for more food. I've eaten half gallons of ice cream in a single sitting. So I've thought about this topic quite a bit.

There are a few odd things about binge eating.

  • Most binge eaters do NOT binge every time they eat, but only on certain occasions. So it's not as simple as saying that for certain people food is "addictive" or that they can't control their food intake.
  • Binge eaters will repeatedly binge despite the unpleasant immediate (upset stomachache) and long term (unwanted weight gain) side effects.
  • Binge eaters will often eat long past the point of enjoying the eating experience - the food no longer tastes or feels good to eat.
  • Food does not seem to have the kind of chemical impact that might explain this behavior, the way illicit drugs or alcohol do - we don't see the kind of dopamine spike from donuts that we get from snorting cocaine, and eating doesn't in itself impair judgment (making us more likely to continue eating) the way psychoactive chemicals (like alcohol) do.
So why does this happen? It seems counterintuitive that people would engage in this sort of behavior, yet many of us do. Over and over again.

I've always had a few hypotheses about binges (these are not original to me). First, binges were the result of out of control blood sugar - if our blood sugar got too high ("spiked") and insulin levels rose too high, the excess insulin would drive blood sugar down too low, triggering a binge. In other words, low blood sugar triggers a binge. Another hypothesis was that if we dieted too long or denied our favorite foods for too long a kind of psychological pressure would build up, resulting in an inevitable binge, like a volcano erupting. Third, binges were the result of some nutritional deficiency, the body's way of desperately trying to acquire some micronutrient that wasn't present in the diet.

I was listing to my new favorite podcast, Sigma Nutrition, and in episode 23 the host interviewed a man named Marc David who works in the field of nutritional psychology. I highly recommend listening to the entire show, but at one point Mr. David suggested a cause for binges that really resonated with me.

Please remember the important distinction between the sympathetic and parasympathetic nervous systems - the sympathetic is activated during fight or flight situations, when you are stressed or anxious. The parasympathetic is activated when  you're relaxed and feeling safe and secure. The sympathetic directs blood away from the gut and into the limbs (so you can run or fight), the parasympathetic directs blood back to the gut (so you can digest your meal) and lowers blood pressure and overall stress.

Now obviously a big meal puts an unusual stimulus on the body - not the kind of stimulus that would make us need to run or fight, but a stimulus that forces the body away from the sympathetic system and towards the parasympathetic. In other words, really overeating signals your systems that you need more blood in your gut, not less, to digest that meal. And that can only happen when the sympathetic system is depressed and the parasympathetic system is activated.

In other words, overeating leads to an immediate, short term activation of the parasympathetic nervous system, which makes you relaxed, calm, and feeling safe and secure.

Now, if you're a binge eater, think to times when you binge eat. I'm going to bet you anything that most binges are triggered by stressful situations, times when you're unconsciously seeking to relax and de-stress, times when life has pushed you into the anxious, jittery end of the parasympathetic-sympathetic axis. 

In other words, for at least some binge eaters some of the time, binge eating might not be the result of a craving for food. It is, instead, the result of a craving for deep relaxation.

Why does it matter why we binge eat?

The approach we take to avoid binge eating has a lot to do with what we believe causes our binges in the first place. If you think that your binges are the result of out of control hypoglycemia (low blood sugar), you're going to try to avoid binges by altering your diet to keep your blood sugar normalized (which isn't a bad thing in itself). However, if your binges is really caused by stress, the blood sugar regulation might not help, and then you're both demoralized and failing to control your binges.

If you think your binges are caused by micronutrient deficiency, you might attempt to stave them off by eating a nutrient rich diet, or carefully going over food logs to find the 'thing' you're missing. Again, this would be doomed to fail. And if you're convinced that binges are caused by some psychological pressure from food deprivation, you might schedule 'cheat' meals (or cheat days! cheat weeks!) in a vain attempt to alleviate that pressure in a somewhat controlled way.

And this, I think, is why so many binge eaters fail to control the binges. 

However, if Mr. David's suggestion is correct, and binges are the result of a search for parasympathetic stimulation, what could we do to address that?

Maybe the way to stave off an oncoming binge is to do something deeply relaxing. Take a walk in the woods. A bubble bath. Meditate for 20 minutes. Watch a comedy show. Whatever you do to de-stress.

This is, of course, easier said than done. Please don't punch me for suggesting that you can overlook that pint of Ben & Jerry's in the freezer by meditating. But it can't hurt to try, can it? 

One 'trick' I use is to promise myself the thing I'm craving... but only after some intervention. I'm not denying myself the ice cream, I'm promising it to myself, but only after the walk, or the meditation. Then, once the intervention is over, re-evaluate and you might be okay breaking that promise and skipping the binge.

Take home point: being aware of your position along the parasympathetic - sympathetic axis may help you alter hard to control behaviors, like binge eating, more efficiently.

And if all else fails, please remember that your binge has not ended the world. Get right back on the healthy eating horse and waste as little time in self recrimination as possible.

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