It’s the diet fad that refuses to go away: juicing. Yes, despite the fact that it’s more-or-less starvation otherwise-sane folk are opting to juice away their lumps and bumps via three-, five-, or even (gulp!) seven-day programmes.

Wheatgrass, kale, spinach, lime, celery, cucumber, beetroot, and carrot are for the more ambitious juicers – novices opt to integrate apple, kiwi, orange, berries, and grapefruits in a bid to make their concoctions more palatable.

Most plans recommend a course of four juices over the course of the day. Water and herbal teas are permitted to keep those (many) hunger pangs at bay, but caffeine, alcohol, and – more importantly – food is out. Still, advocates swear you can shed up to a stone in five days.

Some opt to go it alone, whizzing up ingredients freshly themselves. Others feel they need expert intervention, having the juices delivered to their door at a cost of at least €80.

Kathryn Thomas, Julianne Moore, and Millie Mackintosh are just some of the names who have given juice a go. Nicole Richie is another fan, admitting “I am what you can call a juice fanatic. I always carry around a green juice. They provide lots of energy when I’m running around.”

Gwyneth Paltrow is more cautious, however. Writing for the Telegraph, she commented: "I've done juice cleanses in the past, and in my 20s I did the Master Cleanse, which left me hallucinating after 10 days," adding: "Be aware: a juice detox can crash your metabolism and lead to future weight gain."

Here, we take a cold hard look at the pros and cons of juice diets:

Good: Stick with it and the plans are a great way to kick-start a general healthy-eating plan and crack bad dietary habits. Your stomach will shrink and you’ll subsequently be satisfied on less food.

Bad: Mid-way through day two you’ll be sorely tempted to dive head first into the biscuit tin while simultaneously ringing the chipper for an emergency delivery.

Good: If you don’t regularly integrate fruits and vegetables into your diet, juicing is a great way to make sure you’re hitting your vitamin and mineral targets

Bad: Most Irish people don’t eat enough fibre as it is – and by blending your ingredients into a juice, you’re removing pretty much all the fibre present in the first place.

Good: If you’re panicking because you don’t fit into your wedding dress a week before your Big Day, juicing could well solve that problem for you.

Bad: Unless you’re committed to overhauling your diet long-term, you’ll quickly put back on any weight lost via juicing very quickly.

Good: Some people claim that once ketosis – where your body begins to break down stored fats – kicks in around day three you’ll no longer be hungry.

Bad: You’ll be miserable for most of the diet. Every tiny morsel of food will seem almost impossibly tempting; every waft of freshly-baked bread or hint of sausages grilling on a barbecue will send you insane.

Good: You’ll free up time ordinarily spent preparing and eating meals, allowing you to read the book you never finished, catch up on much-needed sleep, or watch a box set.

Bad: You’ll become a social recluse. You won’t be able to meet friends for a drink, lunch, brunch or dinner. Being around food while you sip water would probably prove too much, but you won’t have the energy or concentration span to bother anyway.