Recent studies are again pointing to the potential of weekly intermittent fasting, where one greatly reduces or eliminates calories on a set number of weekdays, to fight disease and prolong life. Jewish tradition has long advocated weekly intermittent fasting, though the practice has become rare today. Maybe it’s time to bring it back.
“Periodic fasting shows the most promise in getting rid of bad cells and making good ones for regeneration and can be applied to all kinds of diseases,” Valter Longo, director of the Longevity Institute at University of Southern California, told the Washington Post.
Variations of periodic fasting have become popular, such as the 5:2 diet, which advocates five days of normal eating and two days of restricting calories by 75%. Studies suggest that such fasting may be beneficial for treating autoimmune diseases, asthma, rheumatoid arthritis, metabolic syndrome, and even cancer.
The 5:2 diet is associated with Mark Mosley, a BBC journalist who popularized it in the United Kingdom. In the United States, a more restrictive version of the diet, known as the “every other day diet,” which advocates restricting normal calorie intake by 75% every other day, has been studied and championed by Dr. Krista Varady at the University of Illinois at Chicago. Though she cautions that the 5:2 diet will only work if one does not binge on the other five days, an effect she says is avoided more easily on the “every other day” fast for reasons still being studied.
All of this reminds me of the ancient Jewish practice known as the Behab fast. Behab is formed of the Hebrew letters bet-hey-bet, numerically two-five-two, which refers to the second day of the week (Monday), the fifth (Thursday) and again the second (Monday). Without the repetition of the Mondays, the name of the diet is basically the 2:5 diet (5:2 read from left to right, ahem), though there is no known connection between Moses and Mosley.
Despite there being other fast days during the Jewish year, growing up, I had never heard of any fasts outside of the dreaded Yom Kippur deprivation, and my family’s idea of intermittent fasting was restricting oneself to little noshes between fresses. On family vacations, the favorite topic around the restaurant table was where we were going to go for the next meal. If the Behab is correctly thought of as an Ashkenazi custom, my family had long forgotten it.
For centuries, the Behab fast was used in the Ashkenazi world for repenting for inadvertent sins throughout the week – “advertent” sins would get their own specific fasts. The choice of days corresponds to the days the Torah is read, not counting Shabbat, of course, when fasting is not done. The custom of reading Torah Monday and Thursday refers to the belief that those are the days of the week Moses ascended Mount Sinai and descended again, respectively.
Despite the association with Ashkenazi custom, the Behab fast goes back earlier than Jewish settlement in Europe and is probably the fasting mentioned in the New Testament, which Jesus criticized as an attention grab. The early Christian Didache, a manual of discipline that almost made it into the Christian Bible, admonishes its readers not to do as the hypocrites (read “Pharisees”) do and fast Monday and Thursday, but rather to fast Wednesday and Friday! Among Jews, the fast was eventually restricted to periods following Pesach and Sukkot and, in recent centuries, has become obscure.
The original purpose of the Behab fast was not weight loss, of course, but repentance and spiritual purification. Regardless of where one falls on the spectrum of Jewish belief, it’s easy to envision fasting a couple of days a week as an act of repentance in our (culinary) consumer culture, and one of walking more lightly on the burdened earth – and it just might add a few years to our lives.
Matthew Gindin is a Vancouver freelance writer and journalist. He blogs on spirituality and social justice at seeking her voice (hashkata.com) and has been published in the Forward, Tikkun, Elephant Journal and elsewhere.