The Pulse


Hairshirt Diets

by Patrick Reynolds

Ever tried on an itchy wool sweater? There's nothing quite like that skin-crawling sensation as you rush to rip it off your body. Makes me cringe just thinking about it. 


For thousands of years people have been actually seeking that horrible feeling. They would fashion vests and robes out of rough, irritating fabric, often coarse goat hair. This came to be known as a hairshirt, or sackcloth, and it's a standard feature of medieval penitents. Everyone from the lowliest monk to the mightiest king would don the hairshirt for several hours a day, all in an effort to purify themselves and get closer to god.

The hairshirt is just one mild example of humanity's fascination with the mortification of the flesh. Since pre-history we have records of people beating, flailing, starving, and otherwise bringing harm to themselves for spiritual purposes. It still goes on today.

You'd think that life is hard enough, that we wouldn't try to make it harder by inflicting hardship and pain upon ourselves. But there seems to be this part of us that hates our bodies. It's kind of understandable. We pass our days pissing, pooping, farting, hungering, and lusting. We smell bad. We ooze fluids. We get sick. We die. The human body is about as far from "pure" as you can get.

And so there's something enticing about transcending the flesh. Intentionally bringing discomfort and pain on ourselves is a denial of our mere physicality. It's a proof of spiritual strength.

Whipping yourself and wearing sackcloth is no longer in fashion. But the urge to deny the flesh persists, and I see it a lot in the exercise and diet choices people make.

When someone has gotten into a bad spot with their body through poor eating and exercise habits, it can be tempting to seek penance through an overly strict and disruptive fitness routine. People make some hard swings, from eating and drinking whatever they want to super restrictive diets that would impress a mendicant monk.

I call these "hairshirt diets", because a significant part of the attraction is in denying the flesh and making your life more difficult than it has to be. 

They all work from the same premise; something that's rigid, inconvenient, and unpleasant must be good for you. Going through these challenges purifies your body and displays your superior spirituality for the world to see.

Some examples of hairshirt diets:

Diets that cut out major food groups

The biggest example here is something like the Paleo diet. If you go Paleo, you've signed on to cutting out all grains, dairy, beans, and sugar. This closes off major portions of the modern diet to you. A meal out with friends becomes a minefield you have to navigate to stay on your path.

The current gluten-free craze is also pretty hairshirty. If you're not in the 1% of the population with celiac disease, gluten poses no risk to your health. But when you bite into a hard, bland, gluten-free snack you think "this tastes so horrible it MUST be good for me."

Fasting diets

The latest diet fad is intermittent fasting. It goes by a lot of different names, (5:2 being the most popular) but the idea is simple. Throughout the week you stop all normal eating and go into fasting mode for 12 to 48 hours, where your food intake is stopped. This results in fewer calories and a mythical set of benefits including more alertness and increased immune response. And you get the bonus spiritual challenge of suffering through hunger pains every week.


Any diet that talks about cleansing or purifying the body is always a hairshirt diet. It could be a weekend juice fast, a seven day detox, or a chalky powder that promises to cleanse your colon, they all prey on the idea that the body is impure and must be purged for optimal health.

Liquid Diets

Drinking your meals is a pretty unpleasant experience, and so people invariably find it appealing as a hairshirt diet. From juicing enthusiasts to Slim-fast consumers, you know you must be doing something right when your meals come in a tall glass and provide zero pleasure.

I don't want to deconstruct each of these diets right here, (will do that in future posts!) But one thing I can say is that the medical consensus on eating is pretty clear. Here it is:

Eat a wide variety of fresh, whole foods, consisting mostly of vegetables and fruit. Have moderate amounts of grains, meat, dairy, and alcohol if you like. Don't go too crazy with the sweet stuff. There's no one good or bad food, rather it's your nutritional spectrum that's important. 

This sounds boring. It's not going to make headlines. But it has the merit of being medically and scientifically sound.

It means you can enjoy all kinds of foods. You don't need to go to extremes to purify the body, or self-flagellate yourself by never eating another piece of bread for the rest of your life. You just need to exercise moderation and reason. YAWN. I know!

The hairshirt diets are undeniably sexy. They scratch that itch we all have of wanting to transcend our weaknesses, to go through a trial by fire and come out pure. But that's not the way your body works. Your body doesn't like extremes. It functions best with a steady intake of fresh food and a steady output of exercise. Surprises are not welcome.

Hair-shirt-diets-image-2.jpgHairshirt diets might get you some short term gains, but decade after decade, fad after fad, they prove unsustainable. If you find yourself attracted to them, know that for all the food you'll be cutting, your ego is the one thing you're feeding. Because that's what all these ascetic practices boil down to. Harming your most beautiful, irreplaceable gift; your body, for the fleeting satisfaction of having done something "hardcore".

Your body isn't something to be conquered. It's something to be nourished and enjoyed. Take off the hairshirt and let it breathe!






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