As the Ashkenazi observant Jews among our readers know, after the pilgrimage holidays of Passover and Sukkot, we pray for the health and well being of those who fast on the B’hab days—an acronym meaning Monday-Thursday-Monday. On the month of Iyar, following Passover, and on the month of Cheshvan, following Sukkot, some Ashkenazi Jews observe three fast days on the first and second Monday and on the first Thursday.
There are still many synagogues out there where they say a special set of Selichot (supplications), for the protection of those who fast B’hab.
There are several sources for this minhag (custom), some recall the fast of Esther and Mordechai, others suggest that since the pilgrimage holidays are a time of great merriment, it’s possible that the pilgrims may have committed sins for which they wish to atone with fasting.
None of the Jewish sources have suggested that fasting on Monday and Thursday and eating all you want the rest of the week is a great diet recipe. But it appears to be taking over the world.
The 5:2 diet, or the 5/2 diet, involves severe calorie restriction for two days a week and normal eating the other five days. It originated and became popular in the UK, and spread to Europe and the USA, and, most important – it is claimed to promote weight loss and to have some additional beneficial effects on health.
“The Fast Diet” is the brainchild of TV medical journalist Michael Mosley and journalist Mimi Spencer. It allows dieters to eat anything they want for five days, but only 600 calories a day on the other two.
Mosley’s choice for his two weekly fast days? You guessed it – Monday and Thursday.
Their book, “The Fast Diet: The secret of intermittent fasting – lose weight, stay healthy, live longer,” has topped bestselling book lists in Britain and the United States this year, with more than a dozen reprints.
Mosley said the diet is based on work by British and U.S. scientists who found intermittent fasting helped people lose more fat, increase insulin sensitivity and cut cholesterol.
He tried this eating regime for a BBC television science program titled “Eat, Fast, Live Longer” last August, when his own cholesterol level was too high and his blood sugar was in the diabetic range. He says he was stunned by the results.
“I started doing intermittent fasting a year ago, lost 8 kgs (18 pounds) of fat over 3 months and my blood results went back to normal,” Mosley told Reuters.
Mosley attributes his diet’s success—an average loss of a pound a week for both women and men—to psychology. “The problem with standard diets is that you feel like you are constantly having to exercise restraint and that means you are thinking about food all the time, which becomes self-defeating,” he explains.
“On this regime you are only really on a diet two days a week. It is also extremely flexible and simple.”
The Shulchan Aruch suggests that Monday and Thursday were picked to be the two days of fasting because these are Yemei Ratzon (days of grace). It points out that Moses went up a second time to Mount Sinai to receive the Torah on a Thursday and came down on a Monday.
There are no supplications being offered along with the Mosley diet plan.