Paleo diets = weight gain
Researchers working with mice say low-carb, high-fat diets don't work and can cause health problems. (Video courtesy University of Melbourne)
Paleo devotee and My Kitchen Rules judge Pete Evans has hit out at reports that the caveman-style diet could actually make you gain weight and put you on the path to diabetes.
A study by Melbourne University researchers on mice has found that following the low-carbohydrate, high-fat diet for just eight weeks could lead to rapid weight gain and a spike in insulin levels.
But in a 573 word post on his Facebook page, the celebrity chef questioned the veracity of the findings and its methodology, and posted results of an alternative study whose results were more positive.
Mr Evans said the Melbourne University study could not be conclusive as it was conducted on mice, rather than human beings.
"The media and also the health organisations are once again clutching at straws. This time it is a study done on Mice - yep you heard that right...mice! You do have to ask the question...who is funding this study, does this university or the professor have any ties with any pharmeceutical [sic] or multinational funding?"
Mr Evans said he had been contacted by many people who said the diet had helped them get better.
"The amount of Australians that have reached out to me to say how the paleo way have helped their type 2 diabetes is amazing, so much so that a lot are off all their medication, proves and illustrates that this way of life is working for so many people. With close to 1 million Australians with type 2 diabetes, the paleo way is a bloody good place to start and of course consult with your healthy health professional that is up to do date with the latest science."
He also pointed to other findings about the effects of the diet published in the European Journal of Clinical Nutrition in April 2015, as well as asking people to visit his website for information on the Paleo diet.
That study, he said, was conducted on human beings and showed that the Paleo diet had benefits for glucose control and lipid profiles.
The post has been liked by 3549 people, it was shared by more than 600 people, and attracted 518 comments, most in support.
Many of those leaving comments on the page shared their own experience of being on the Paleo diet and having achieved positive results.
Commenter Karen Collins said even her doctor was impressed by the results of her being on the diet.
"What would they know!!!!! I've experienced the results and never eaten so well!!!!! Even my blood tests show the results. They don't understand and haven't even got their facts right. My Doctor was impressed with how I'm doing."
Another response from Kelly Martin said they were all "living proof it works well for Humans."
"They don't speak of the fermented cultured intake of foods we eat for good gut health. Just grains, bread, and sugar we have removed?? Etc. Etc."
However, the Melbourne University study's findings are so alarming, they have prompted the study's lead author, Associate Professor Sof Andrikopoulos, to issue a warning about the fad diet.
Professor Andrikopoulos said the diet could be most risky for people who are already overweight and lead sedentary lifestyles and even more dangerous for people with pre-diabetes or diabetes.
The study, published in online Nature journal Nutrition and Diabetes, was originally intended to demonstrate the benefits of a low-carbohydrate, high-fat diet for people with pre-diabetes.
Researchers took two groups of overweight mice with pre-diabetes symptoms and put one group on a low-carbohydrate, high-fat diet.
The proportion of fat in their diet increased from 3 per cent to 60 per cent. Their carbs were reduced to only 20 per cent.
The other group ate their normal diet.
After eight weeks, the weight of the Paleo mice ballooned by 15 per cent and their fat mass doubled from 2 per cent to almost 4 per cent.
"We are told to eat zero carbs and lots of fat on the Paleo diet. Our model tried to mimic that, but we didn't see any improvements in weight or symptoms," Professor Andrikopoulos said.
"In actual fact, they gained more weight, their blood sugar levels were higher, their glucose was even worse."
Researchers believe the results would be mirrored in humans, because of the similarities in mouse and human genomes.
To put that in perspective, a 100 kilogram person on a Paleo diet could pile on 15 kilograms in two months.
"That's extreme weight gain," Professor Andrikopoulos said.
"In humans, this level of weight gain will increase blood pressure and the risk of anxiety and depression and may even cause bone issues and arthritis.
"The bottom line is it's not good to eat too much fat."
Professor Andrikopoulos urged would-be dieters to seek professional advice.
"What people don't understand is that looking good is a celebrity's day job," he said.
"When you think about it, celebrity advocates of these diets are often very active and can handle an increased fat load, rather than your average Australian who is a lot less active.
"If you put someone with a sedentary lifestyle on a high-fat, low-carb diet, I bet you that person will gain weight."
Professor Andrikopoulos said the Mediterranean diet was the best for people with pre-diabetes or diabetes.
"It's backed by evidence and is a low-refined sugar diet with healthy oils and fats from fish and extra virgin olive oil, legumes and protein," he said.