Hall says he gave up all food except for beer for Lent – an idea inspired by Bavarian monks.
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“As a student of beer I had always heard the story of the Bavarian monks who gave up solid food and lived on beer,” says Hall, who does not identify as religious. “I wanted to fact check that idea by recreating it in modern times.”
In addition to the two to five daily pints of beer, Hall’s 20-day diet – which he documented on his YouTube channel – included black coffee and tea (without sugar, sweetener or milk), water and a daily multivitamin.
However, Hall, who works as director of sales at Fifty West Brewing Company, says he would not recommend his diet to others.
“I would not recommend this as I am in a unique situation. I drink beer for a living.”
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Few would endorse this kind of diet, and unsurprisingly it has been criticised by a medical expert.
Dr Clare Morrison, GP for online doctor and pharmacy MedExpress, says she would not endorse this sort of dieting.
“There are a lot of drawbacks to this extreme diet, and therefore, I wouldn’t recommend it,” Dr Morrison tells Press Association.
“The overall lack of macro-nutrients, such as protein and fat, will cause a big reduction in the body’s metabolic rate, leading to fatigue, light-headedness and poor concentration.
“The lack of protein will also cause muscle wasting and weakness, as well as lowering resistance to infection.”
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Morrison also stressed the dangers of drinking so much alcohol – the effects of which have been extensively reported in the past.
Hall isn’t the first to lose weight with a technically unhealthy diet. Last year, a man lost over a stone after eating nothing but McDonald’s for 30 days.