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It’s proven to be one of the most popular (and controversial) diets in recent years, but new research suggests that the modern Paleo dieters are, well, doing it wrong.

A key principle of the Paleo diet is the exclusion of starch-rich vegetables and grains – a food group that findings published in the Quarterly Study of Biology say not only played a major factor in the evolution of the human brain. Apparently, it’s also a food group that the original Palaeolithic humans would not have evolved without.

It challenges the long-held belief that increased meat consumption was solely responsible for the evolutionary increase in brain size that got humankind to the point we’re at today.

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“Our research suggests that dietary carbohydrates, along with meat, were essential for the evolution of modern big-brained humans,” says co-author Professor Jennie Brand-Miller from the Charles Perkins Centre.

According to the study, a low carbohydrate diet similar to the modern Paleo diet would not have provided enough glucose needed to enable the development of modern human’s large brains. (Post continues after gallery.)

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While starches have been readily available in seeds, fruits and nuts since some of the earliest human populations, it was when cooking became more of a common practice (researchers pinpoint this as around one million years ago) that more evolutionary changes occurred.

“After cooking became widespread, starch digestion advanced and became the source of pre-formed dietary glucose that permitted the acceleration in brain size,” co-author Professor Les Copeland said.

Researchers say that their evidence shows a change in the number of salivary amylase genes, which increase the amount of salivary enzymes produced in order to digest starch, occurred at a similar time.

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So where do we go from here?

Amidst all the current concern about global obesity rates, which many believe is what has made the Paleo diet so popular today, the study’s researchers argue that a diet similar to the one eaten in the Palaeolithic era would still be good for us today.

But unlike the rules the modern Paleo diet abides by, the diet should include foods like potatoes, yams and sweet potatoes in addition to newer starchy grains like quinoa, corn, wheat, oats and rye.

“It is clear that our physiology should be optimised to the diet we experienced in our evolutionary past,” Professor Brand-Miller said.

This is not the first time the Paleo diet, which encourages consumption of mainly meat, fish, a restricted list of vegetables and fruit and bans dairy and carbohydrates, has come under fire.

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Nutritionists have previously raised concerns about its nutritional value, as well as the inaccuracies and double standards of including foods like 'Paleo brownies' in the diet.

Celebrity chef Pete Evans, a prominent Paleo supporter, also faced backlash after it was claimed a recipe for bone broth in 'Bubba Yum Yum', a Paleo children's cookbook he co-authored, could be potentially harmful for babies.

Are you for or against the Paleo diet?

10 foods you never knew were healthy

Bread

KATIE THOMSITT, Dieticians Australia spokesperson says: "Lots of people shy away from bread to achieve weight loss. But bread is such an important source of fibre, and plays such a helpful role in weight loss and preventing bowel cancer. A couple of slices of a dark, seedy bread per day is absolutely fine."

Cheese

KATIE SAYS: "Cheese is definitely a higher fat source of dairy, but still a good dairy fat. Choose low-fat options if you have it regularly, otherwise consume it in moderation. One serve of dairy is 30g, so a couple of slices is absolutely fine."

Chocolate

KARA LANDAU, The Travelling Dietician says: "Studies have been able to show that dark chocolate can improve insulin sensitivity, reduce blood pressure in healthy individuals, protect against heart disease, and improve HDL good cholesterol (not a bad start for such a tasty food!). Dark chocolate also contains polyphenols, whilst white chocolate does not. These polyphenolic compounds are able to relax blood vessels allowing for better blood circulation, and thereby assisting with the maintenance of healthy blood pressure levels."

Coffee

KATIE SAYS: "Coffee is a really good snack, in particular if its milk-based to get the dairy in - for example, a skim latte. As long as its in moderation - daily guidelines say a maximum of three per day! And you want lots of water on top of that."

Eggs

KARA SAYS: "Yes, even the yolks are good for you! Healthy fat soluble vitamins, as well as half the protein found in an egg, are all found in the yolk!"

Avocado

KATIE SAYS: "Avocado is a healthy fat. Lots of people think its high-fat and not good for you, but its rich in mono unsaturated fats, which give you protection against heart disease. It also helps with controlling lower cholesterol levels."

nuts

KATIE SAYS: "Nuts fall into the same category as avocado - they have lots of healthy oils and fibre."

dairy

KARA SAYS: "Often milk and yoghurts are fortified with Vitamin D (a fat soluble vitamin) which requires a small amount of fat to be present in order for the body to absorb it, therefore having the full fat variety can be of value to enhance the nutritional benefits from the products' consumption. The fat in the dairy also aids with satiety, which could prevent unhealthy snacking at a later point in the day."

Potato

KATIE SAYS: "Potato always gets a bad rap as a starchy vegetable, but it's an excellent source of fibre. Sweet potato in particular is great for weight management and sugar level control. Potatoes are also really rich in potassium."

Red meat

KARA SAYS: People tend to restrict red meat unnecessarily, thinking that its high in saturated fat. "But lean red meat is high in protein, CLA (which has been found to be associated with lower body fat percentages), B12, iron and zinc. These are all nutrients we want to get into our body!"