There is little scientific evaluation of the relatively recent paleolithic phenomenon. Some dietitians are more declarative. "There is no scientific research to back it up at this stage," says Margaret Hayes , spokesperson for the Dietitians Association of Australia.

The pillars of the paleo regime are lean meat, nuts, fruits and vegetables – foods that our ancestors would have hunted or gathered. Processed foods, dairy, legumes and carbohydrates are out. But there are three major pitfalls that can ensare the paleo dieter.

Balance

Paleo, popularised in a 2002 book by health professor Loren Cordain, instructs followers to balance their consumption of lean meats with fruits and vegetables. But maintaining that balance can prove difficult.

Nutritionist Julie Upton told The Huffington Post many of her clients – mostly athletes – gain weight because they binge on meat and protein but forgo veggies.

"They miss the point that you're supposed to eat a lot of vegetables and some fruit while following paleo," she said.

As with any diet or nutritional program, discipline often goes out the window, Ms Hayes says.

"People take out of it what they want to hear," she says. "For some people, they'll do their own version of it. If it means that they're choosing a diet higher in fruit and vegetables than they would have previously then that's a great thing, but if they're just choosing the meat part of things, that's not a great thing."

Eliminating carbohydrates, dairy and legumes is also contrary to best nutritional practice, Ms Hayes  advises.

Calories

The paleo diet does not count calorie intake – that's up to the individual. Whether this is liberating or ruinous depends on how well you can rely on your own judgment.

At its most rudimentary, weight loss is about restricting the calories you consume while increasing the amount you burn off. And some food groups included on the paleo platter are rich in calories, according to Ms Hays.

"Nuts and seeds and fats and oils are very dense sources of calories. You don't have to eat very many to get a large calorie whack," she says.

If someone doesn't lose weight on paleo or any diet, it's because they are eating too many calories," nutritionist Dawn Blatner told The Huffington Post.

Snacks

Adding to the calorie count, and often flagrantly breaking the rules of paleo, are the snacks people buy from supermarkets and grocery stores – which may be sold as paleo products but actually contain artificial sugars.

"You may think you're on a paleo diet when you're not; you're eating paleo-branded junk food," says Dave Asprey, author of The Bulletproof Diet.

For example, recipes abound this Easter for low-sugar, low-gluten paleo hot cross buns. Ms Hayes  has seen "paleo muesli" and says products marketing themselves as paleo-friendly are often expensive and make it hard for people to stick with the diet.

Her recommendation? Follow the Australian dietary guidelines, which are based on decades of scientific research, eat in moderation and beware fads that may not work for you.

"As a dietitian, it's not one blanket rule [that] fits all. It's tailormade for the individual," she says.