Recently by Mark Sisson: No More Styrofoam Rice Crackers forUs!
We all make poor choices against our better judgment. It’s kind of what makes us human — the tendency to actively and willfully make decisions that will result in unfavorable outcomes. Sure, the candy bar tastes good, but you know you’ll feel awful after eating it. Yeah, that blog is fun to read, but you know you’d be much happier if you finished that essay for class first. And yet five minutes later, a candy bar wrapper sits, emptied of its contents; your molars house fragments of nougat and sport a caramel sheen; light nausea approaches; and you find yourself wading knee deep through comment sections, MS Word window minimized. What just happened? Why did you do those things that you told yourself you wouldn’t, that you warned yourself against, and whose negative ramifications are already coming to fruition — just as you predicted?
Last week, we began the dialog with my introductory post on akrasia — the act of knowingly working against one’s own interests — but we didn’t get into any details. Today, I’m going to try to provide a few answers. I’m going to delve into the reasons for akrasia, particularly as it pertains to making bad eating choices. I won’t discuss psychological issues, per se, instead focusing on physiological explanations, but keep in mind that the two are often one and the same. You can’t really separate the mind from the body (well, without killing the person, that is).
Whether we pick up the phone to order takeout, open the candy wrapper, shove the spoon into the jar of Nutella, or accept the offered slice of cake, we are making a decision. Most health experts say making the healthy decision is a matter of willpower. So that if you make an unhealthy decision you simply don’t want it badly enough. Like Bob Newhart in that old Mad TV sketch, they seem to think all you have to do is just “STOP IT!”
Well, it’s not that easy. Otherwise, folks wouldn’t be making these decisions that go against their better judgment. Otherwise, they’d indeed be “stopping it.”
So why do we do it?
Many — perhaps most — poor dietary choices stem from an inability to resist cravings. And who can blame you, really? Whether they’re for chips, sweets, or something specific like wheat, cravings are difficult to ignore by design. Their very purpose is to get you to give in to them, to override your rational side and promote decisive, single-minded pursuit of whatever it is you crave. Something, then, is at the heart of these cravings. Something physiological. But what?
1. You’re missing something from your diet and your ancient genes are misinterpreting the modern cravings.
There’s often a disconnect between what our animal bodies need or desire and what our human minds know is best. When the animal body perceives a deficiency, some nutrient lacking in the diet, like salt, it often develops a craving for that nutrient. 20,000 years ago, if you were salt-deficient you would have gone looking for shellfish or rock salt, because those are the salt sources you knew. Your food memory bank was rather limited in scope. Today, that same salt deficiency might manifest as a craving for Pringles or Cheezits, because those foods are listed under “salt” in your food memory bank.
Let’s look at some research on the subject. In one study (PDF), human volunteers were put on a strict low-sodium diet and treated with diuretics for ten days, rendering “substantial sodium depletion.” The effects were pretty telling. Salt thresholds — the minimum detectable level of sodium chloride dissolved in water — lowered dramatically; the subjects could detect lower levels of salt during sodium-depletion than they could during sodium-repletion. Furthermore, salt depletion made salty foods taste better than they had before the study, and salt-depleted subjects rated the saltiest foods as the most attractive and desirable.
It’s quite possible that your “Pringles cravings” are actually salt cravings, and that the former is simply what your animal body associates with “salty.”
2. You’re missing something from your diet and your modern self is misinterpreting the ancient cravings.
What about sweet cravings? Paul Jaminet thinks that sugar cravings might actually be fatty meat cravings. It sounds crazy on the face of it, but he makes some salient points. First, certain amino acids are actually slightly sweet. These sweeter amino acids are also hydrophobic, which means they are found inside cells with fats, and they repel water (fat doesn’t mix with water). Hydrophilic amino acids, which are water-soluble, do not associate with fat, and trigger the umami tastebuds, are not sweet. A leading theory of sweetness even suggests that in order for a compound to be sweet (to interact with sweetness receptors), it must be hydrophobic. Paul suggests that in a Paleolithic environment with ample prey, bland (rather than sweet) tubers and less abundant/seasonal fruits, cravings for sweets drove us to eat calorie-dense, nutrient-rich fatty meat.
It’s possible, yet again, that our animal bodies are confused by the modern (and totally understandable) conflation of sweet with sugar and misinterpret what is actually a need for fat. Perhaps those sweet cravings turn into sugar binges because sugar isn’t actually what your body wants.
3. You’re addicted to wheat.
Wheat contains opioid peptides that may be able to activate opioid receptors in our bodies. You know what else activates opioid receptors? Opium, morphine, and heroin. (I’ve never tried any of them, but I hear they can inspire some real devotion from their users. See: Trainspotters, Requiem for a Dream.) I know that may sound glib, and I’ll be the first to admit that research into this is still very preliminary. You won’t find any ironclad evidence on PubMed that wheat is addictive. But the thinking goes that rather than hitting you like a ton of bricks and rendering you speechless from the sublime triggering of your opioid receptors, wheat addiction manifests as a stubborn lingering thing.
Evidence does exist, however limited. One older paper (PDF) that identifies multiple opioid peptides in wheat gluten, suggests that they are capable of binding to brain opioid receptors via a “plausible biomechanical mechanism,” and deems them of “physiological significance.” Dr. Emily Deans, of Evolutionary Psychiatry, has actually used naltrexone — a drug that blocks opiate receptors — to curb wheat cravings in celiac patients who are trying to kick the “habit.”
Wheat plays a huge role in the diets of industrialized nations. If you’re reading this, you probably grew up eating it. You may still be eating it from time to time — and that may be at least partly responsible for your urge to eat that slice of bread.