Can Yom Kippur Fasting Make You Fat? Yes, if You're Not Careful

A diet counselor serves up a survival guide to the High Holy Days.

It sounds counterintuitive to worry about getting fat on Yom Kippur.

It is, after all, a holiday that’s all about forgoing sustenance in order to repent for your sins. So how in the world, you may ask, can fasting get you to a place where it’s harder to button up your pants in the Jewish New Year?

Diet counselor Navah Uzan warns that it’s all too easy to end up consuming far more calories over Yom Kippur than during a typical 24-hour period eating three meals a day. The two big danger zones, she says, are the meal on the eve of the holiday, when the fast begins, and then the meal when one "breaks the fast" at Yom Kippur’s end.

“People are funny,” she says. “At the aruchat mafseket, the pre-fast dinner on the evening before the holiday, we feel that we have to eat much more than we usually do so we don’t feel hungry the next day. And then, afterwards, when we end the fast, we tell ourselves that we "deserve" to eat because we are so hungry after not eating all day. The big problem is that people think that breaking the fast is a free-for-all."

In the course of those two massive meals, she says, people can easily consume double the number of calories than they would normally over the course of a day. The key to preventing Yom Kippur weight gain is preparation, moderation and correct food choices - even if that means breaking with some timeworn family traditions.

She advises:

Withdraw from caffeine and hydrate before fasting. Uzan recommends that anyone who is used to drinking coffee or other caffeinated drinks slowly taper off over the course of the week before the fast. “Caffeine withdrawal is what’s going to make your fast harder - that’s what’s going to give you a headache and make you feel you are suffering.” The day before the fast, drink water often - have a glass of water at least every two hours, to get enough fluid in your body for the drought the next day.

Don’t eat too much before the fast. When people overeat in the pre-fast meal, Uzan says, their insulin level shoots up and they can easily start feeling hungry the very same evening, especially if many of the calories in their meal came from simple carbohydrates like pasta or potatoes or rice, or from sugary drinks or dessert. “If you need to load up, load up on the proteins - that’s what will hold you and keep you feeling full - fish or chicken or meat, and at least two kinds of vegetables - like a salad plus a cooked vegetable. You can have a small portion of complex carbohydrates like whole wheat bread or half a cup of beans. Watch the salt - too much salt will make you thirsty.”

The most challenging parts of the fast day, Uzan says, will be your regular meal times - when your body is used to being fed. For those who are normally on diet plans that strictly regulate when they eat, the urge to nosh at those times will be even stronger. “There’s nothing you can do - you’re going to be hungry. Just grit your teeth and get past it.”

You want your New Year to be sweet - but sugar is no way to break the fast. Many Jews traditionally break the Yom Kippur fast with something sweet to kick their blood sugar into gear quickly - a piece of sweet challah bread drizzled with honey, or a slice of cake and tea or coffee with sugar. That, Uzan says, is a recipe for disaster. “I grew up in a nice Polish house where we would break the fast with kugel and wine. That’s really bad news. When you start eating again with something sweet, your insulin spikes up and you get even hungrier than you were when you were fasting. Then the floodgates open and you’re ingesting 3000 calories before you know it. 

In the diet support groups she runs, Uzan instructs participants to break their fast with an unsweetened drink, and a sandwich comprised of light bread with ‘some form of protein’ like cheese, tuna, or a hard boiled egg or turkey, and lots of vegetables.

After they have their sandwich - and this is the key, she says - they must wait an hour. “After that hour, you should sit down to a nice normal, regular meal - it can be a festive meal - with a salad, many vegetables, and a main course that contains protein. By waiting for the meal, after you allow your body to be satiated with your sandwich, you don’t face a table full of food when you are starving.”

After that meal, she says, they must wait another hour - and if they are still hungry after that, have a few pieces of fruit. While a bite of dessert at the end of the meal “won’t kill you” - she cautions that it can be a trigger to continue to eat, and if you can resist the sugar, that’s best.

More than anything, the secret to staying sane and slim on a fast day, she contends, boils down to your attitude. People who are trying to lose weight or maintain a weight loss, she says “are terrified of the High Holy Days. It’s especially hard for people who are Orthodox Jews, but really - for everyone its a non-stop food fest, with one big meal right after the other, it has the potential for disaster. But you can’t go into it being scared and negative, think positive, be confident and tell yourself that you are in control.”

If, despite your best efforts, you "lose it" over the holiday, she says, don’t let it turn into a downward spiral. Even if you eat too much at one or two holiday meals, it’s important that afterwards, you carry on as usual. The day after breaking the fast, don’t skip meals the next day to try to compensate for the calories consumed, and fall in a pattern of starving and binging.

Instead, get back into a healthy routine, and soon, hopefully, you’ll get back into your jeans as well. 

Eran Wolkowski