LONDON: One recommends sitting in a cold bath after drinking black coffee, while another involves being fed through an intravenous drip.
They are among the top five celebrity fad diets that experts have warned should be avoided in the New Year.
The British Dietetic Association said that diets followed by the rich and famous were becoming "more extreme" and increasingly involved "medical intervention".
Dieticians warned there really is "no quick fix" to a slim, trim body for 2013 and said that following celebrity fads could lead to health problems.
Among the most disturbing entries was the Ketogenic enteral nutrition diet, said to be followed by top fashion models.
The KEN diet involves eating nothing at all. Instead, a liquid formula is administered through a feeding tube inserted through the dieter's nose. You are attached to a portable pump and liquid bag for 10 days and can unhook yourself for only 60 minutes every 24 hours.
BDA consultant dietician Sian Porter described the procedure as "shocking" and something "usually reserved for the chronically ill".
The list also included the bizarre party girl IV drip diet. Offered at private clinics for about STG225 (RM1,125) a time, it involves a high-dose cocktail of vitamins and nutrients administered via a drip of the type used to treat the severely malnourished and clinically ill, supposedly providing a "power boost".
Porter said: "There is little evidence that this even works in well people. Even if it did, food and drinking water or other healthy drinks is preferable to having an IV drip inserted into your body."
She added: "Our concern is that many of these diets are quite invasive. It shows the extreme lengths that people are willing to go to in order to lose weight.
"Eating is a pleasure and people should enjoy their food."
The carb-free Dukan diet was named as the worst offender for the third year in a row. The Dukan Diet became the bestselling diet book of all time, with more than a million copies sold in Britain alone. It is credited with Carole Middleton's svelte figure at her daughter Kate's wedding to Prince William.
But the BDA described it as "confusing, time-consuming, very rigid" and warned it could cause "lack of energy, constipation and bad breath".
The six weeks to OMG (Oh My God) diet was dismissed as "six weeks of hell and isolation". Its London-based creator, Venice A. Fulton, recommends doing exercise first thing in the morning after drinking black coffee, and sitting in a cold bath to burn stored fat.
The BDA attacked as "madness" the increasingly popular alcorexia or drunkorexia diet, which encourages followers to shun calories during the week so that they can binge on alcohol at the weekend. Porter said: "After Christmas, people often look for a quick fix. They see air-brushed celebrities and aspire to look like that.
"But if it looks too good to be true, it usually is. We see new health fads and diets every year but there is no substitute for exercising and a balanced diet."
Helen Davies, spokesperson on behalf of the Dukan Diet, said: "The BDA's only criticism of the Dukan diet is that it's 'confusing, time-consuming (and) very rigid' - some would say this is a very necessary part of changing any sort behaviour pattern - and somehow the BDA judge this to be worse than feeding yourself via a drip or replacing food with alcohol?" - DM
Credit to DM and NST