A new editorial denying the role of saturated fats in heart disease has sparked controversy and an angry backlash from experts in the field.
The editorial states that a widely held belief that saturated fats clog up arteries, leading to coronary heart disease, is just "plain wrong".
The reason we're advised to avoid saturated fats is to do with blood cholesterol, the waxy stuff that can build up in your arteries. All cholesterol is not the same, though - there's a distinction between 'good' high-density lipoprotein (HDL) and 'bad' low-density lipoprotein (LDL) cholesterol.
Standard advice goes that if your diet has too much saturated fat - think junk food, cakes, processed foods, chips - LDL cholesterol can build up and increase your risk of heart disease.
Now a hotly debated editorial is saying we should forget all that, and instead focus on exercising and eating "real foods".
"Decades of emphasis on the primacy of lowering plasma cholesterol, as if this was an end in itself and driving a market of 'proven to lower cholesterol' and 'low-fat' foods and medications, has been misguided," a team of three cardiologists writes in the latest issue of the British Journal of Sports Medicine.
The lead author of the editorial is controversial British cardiologist Aseem Malhotra, who has an established media profile in the UK as a proponent of high fat diets.
In fact, just last year another report co-authored by Malhotra sparked outrage, as it gave people dietary recommendations in conflict with evidence-based guidelines put forward by other public health organisations.
The report was authored on behalf of the UK's National Obesity Forum, and four members of the organisation resigned in the fallout, stating they had not been consulted before the report was released.
"Eat fat to get slim. Don't fear fat. Fat is your friend. It's now truly time to bring back the fat," Malhotra told the Press Association last year.
Now his latest article is once again perpetuating that message, citing a "landmark systematic review and meta-analysis of observational studies", which showed no association between saturated fat intake and heart disease.
But it must be noted that observational studies are not really the most reliable type of evidence, as they don't establish causation, and it's hard to weed out possible bias.
There is so much research on dietary fat and heart disease that it would be easy to cherry-pick the studies that support your particular conclusion.
We do have solid evidence from clinical trials that cutting back on saturated fats in your diet reduces 'cardiovascular risk', such as heart disease and stroke.
And even though it's false to think that saturated fats directly clog the arteries, experts say that's not even what health authorities are claiming.
"Where the article is most misleading is the description of the current paradigm," says cardiologist Garry Jennings, chief medical advisor of Australia's National Heart Foundation.
Jennings adds that the authors of the editorial present "a mixture of truths, half-truths, and misconceptions".
"There are a number of poor and discredited studies quoted to support the arguments presented and confusion between high total fat in the diet and high saturated fats," he says.
Malhotra and colleagues conclude that evidence shows regular brisk walking is a good preventative measure of heart disease, and that it's important to address inflammation of the arteries instead of watching out for saturated fat which leads to high LDL cholesterol.
"People with high LDL cholesterol have more heart attacks," says Jennings. "There is more to it than this but leaving LDL cholesterol out of the story is misleading."
Physician David Sullivan from Royal Prince Alfred Hospital is also critical.
"[I]t is likely to exacerbate the confusion and distrust that surrounds dietary advice for the prevention of cardiovascular disease," he says.
"By recommending a cholesterol-raising nutrient without providing a counterbalance, the authors want to have their cake and eat it. They justify this high-risk approach with the assertion that one of the most thoroughly researched areas of medical science is a hoax, but this is not the case."
The editorial does recommend that the best lifestyle change you can make is regular light exercise and a Mediterranean diet (high in 'healthy fat' sources such as olive oil, nuts and oily fish), which at least is some advice that isn't controversial.
"The Mediterranean diet and daily exercise can help reduce heart disease risk," associate medical director at the British Heart Foundation, Mike Knapton, told Beth Mole at Ars Technica.
"But I'm afraid the claims about saturated fat made in this opinion piece are unhelpful and misleading."
Judging from expert opinions, it looks like this new editorial is more likely to confuse the public than help us understand the latest developments in heart disease research.
The editorial was published in the British Journal of Sports Medicine.