cardiovascular disease Centre for Global Dialogue cholesterol CVD diabetes diet heart hypothesis Heart Disease low-carb low-fat Pharmacy Swiss Re The BMJ

Diet-heart hypothesis: zombie or written in scientific stone?

Diet-heart hypothesis: zombie or written in scientific stone?

Diet-heart speculation: zombie or written in scientific stone?

By Marika Sboros

The diet-heart speculation is a curious creature. To some scientists and physicians, the speculation that saturated fats causes coronary heart illness is a zombie. Regardless of all of the stakes they drive deep into its coronary heart, it simply gained’t die.

To others, it’s written in scientific stone. That’s even when supporters, akin to Harvard vitamin and epidemiology professor Walter Willett, name it “incomplete” and “overly optimistic” in its classical type.

The speculation hovered in the wings at a groundbreaking convention in Zurich, Switzerland in June. That’s when it wasn’t taking centre stage. Willett and others vigorously dispute the notion of any terminal gap in the diet-heart speculation.

That is the second of a two-part evaluate of an occasion that was a singular collaboration between international reinsurer SwissRe and The BMJ.  The venue was auspicious, Swiss Re’s Centre for International Dialogue in Rüschlikon that homes its analysis arm, the Swiss Re Institute.

Dr John Schoonbee. Image: David Ausserhofer

That raised the query why the world’s second-largest reinsurer is concerned in contentious vitamin science debates. Swiss Re’s chief medical officer Dr John Schoonbee stated tons about that.

“If more people die, we pay out more,” Schoonbee stated. “If less people die, we pay out less. So, we want to keep people living longer, healthier lives.”

He and Swiss Re’s head of life and well being merchandise Canada Emile Elefteriadis elaborated in observations in The BMJ. Their article was half a collection that The BMJ commissioned and revealed as a part of the convention. Co-authors of scientific papers needed to embrace at the very least one scientist or skilled with vastly divergent views from the remaining.

Of their observations, Schoonbee and Elefteriadis pose and reply the query: Why would a number one international reinsurer have an interest in vitamin?

Questionable coverage selections

They are saying that understanding of vitamin is usually poor due to conflicting proof and vested curiosity affect. This has led to “questionable downstream policy decisions”.

These selections have “massively influenced the outcome of world health and individual wellbeing”. And the monetary well being of life insurance coverage portfolios and nationwide well being methods, they are saying.

The appropriate coverage selections would have measurably totally different influence on particular person and societal well being.

Click on right here to learn: Teicholz: How low-fat diets may cause a coronary heart assault


To that finish, Swiss Re has developed a focused life insurance coverage mannequin. The purpose: to evaluate the inhabitants impact of vitamin methods on well being. Particularly, methods to scale back longer-term danger markers related to sort 2 diabetes, prediabetes, and metabolic syndrome.

If all these affected adopted such a technique, the mannequin estimates an annual discount in complete demise claims of 13%, Schoonbee and Elefteriadis say. That interprets to substantial features for all times insurers paying billions in dying claims yearly.

Additionally they say that it might scale back untimely lack of life from preventable, reversible circumstances.

The convention organisers clearly hoped to clear some confusion with the four-day occasion.

The primary two days coated Meals for Thought, the Science and Politics of Vitamin. Click on right here for a full speaker record. The final two days coated Redefining Diabetes, Placing a “Chronic, Progressive” Illness into Remission. Click on right here for a full speaker record.

Miracle assembly?

Dr Fiona Godlee. Image: David Ausserhofer

BMJ editor-in-chief Fiona Godlee opened the primary day with the assertion: “There is no such thing as a miracle diet, but there is such a thing as a miracle meeting. And in my view, this is it.”

Godlee wasn’t incorrect. There have been “miracles” of types, although not in the best way she might have hoped.

Audio system with vastly totally different opinions on optimum vitamin and on each side of the plant- versus animal-foods divide engaged on the identical stage for the primary time. They usually debated main scientific controversies.

Chief amongst these: well being claims round saturated fat – in different phrases, the diet-heart speculation. And low-carbohydrate, high-fat (LCHF) diets and their polar reverse low-fat, high-carb diets that dietary tips enshrine.

Canadian cardiology professor Salim Yusuf stated that the speculation is the results of “brainwashing” by a “questionable study” a few years in the past. Yusuf is chair in heart problems at McMaster College Medical Faculty in Hamilton, Ontario.

Prof Salim Yusuf. Image: David Auserhoffer

He was referring, in fact, to Ancel Key’s Seven Nations Research that he launched in 1958 however solely revealed 20 years later. It has turn into “ingrained in our DNA”, Yusuf stated.

It’s also the bedrock on which specialists constructed the dietary tips that the US launched onto an unsuspecting public in 1977. And the remainder of the English-speaking world adopted thereafter.

Rising consensus?

Yusuf can also be principal writer of the PURE research. PURE is the most important research investigating hyperlinks between carbs, fat, heart problems (CVD) and dying. Amongst conclusions: the extra fats you eat, together with saturated fats, the decrease your danger of dying from coronary heart illness. And the upper your carb consumption, the extra your danger of untimely demise rises.

That led to rising consensus of types. Yusuf and Tufts College vitamin professor Dariush Mozaffarian have been amongst those that agreed that there was no proof to help present guideline caps on saturated fats.

Supply: D Mozaffarian

That would have seemed just like the demise knell for the diet-heart speculation. As an alternative, it highlighted one other main convention theme: what proof to belief – or not, because the case could also be. And thru all of them ran the divide of plant-based diets versus animal meals.

Mozaffarian can seem like he sits in the center together with his graphic on meals to want, eat reasonably (in the center) and keep away from utterly. (See proper)

Amongst proponents of plant-based diets have been Willett and Nita Ghandi Forouhi (Cambridge) in the UK who help the view that plant-based diets are more healthy.

And that “much of the evidence (epidemiological) suggests that replacing saturated fat with polyunsaturated fats (including plant oils) reduces the risk of coronary heart disease”.

Jaundice view of epidemiology

On the opposite aspect have been these selling animal meals as more healthy – and a jaundiced view of epidemiology. The US contingent included Prof Stephen Phinney,  Dr Sarah Hallberg and science writers and authors Nina Teicholz and Gary Taubes from the US. From the UK have been heart specialist Dr Aseem Malhotra, public well being researcher Dr Zoë Harcombe and others.

US science journalist Nina Teicholz and UK Prof Martin White. Image: David Auserhoffer

The plant-versus-animal-foods divide was not as clear-cut as epidemiology versus randomised managed trials (RCTs).

Harcombe stated that she doesn’t mechanically belief RCTs both. There must be much more reporting and selling non-significant outcomes that was presently the case, she stated.

Harcombe cited Hooper 2011 on Decreased or modified dietary fats for stopping heart problems (CVD). The researchers discovered one vital outcome regarding CVD occasions (coronary heart assault and stroke) and 11 non-significant outcomes.

Non-significant findings inform us “what we don’t need to worry about, which is far more than the one claim that we do (CVD events – which doesn’t hold either)”, Harcombe stated.

Each epidemiology and RCTs got here in for a sound thrashing by way of video hyperlink from Stanford College Prof John Ioannidis. Ioannidis stated that 95% of vitamin analysis is “in bias”.

Epidemiology’s “typical recipe” of vitamin analysis results in failure. He recognized “large measurement error”,  “cherry-picking among multiple hypotheses” and meals business affect as obstacles. Additionally “strong beliefs” – private, spiritual and cultural –  and “white hat bias”. That’s the time period for “bias resulting in distortion of research-based info in the service of what could also be perceived as ‘righteous ends’“.

‘Hijacking’ of the proof

RCTs even have “tremendous bias”, Ioannidis stated.

Prof Dariush Mozaffarian (left) and Dr Aseem Malhotra. Image” David Auserhoffer

Malhotra later advised the convention that business pursuits have “hijacked” the most effective obtainable medical proof. He additionally stated that root explanation for weight problems and sort 2 diabetes is “flawed science”.

Godlee soldiered on, in search of consensus. There was one huge reversal in typical considering, she stated: the demonization of fats. Nevertheless, she expressed shock that there didn’t look like any vital “mea culpa” from the scientific group that it had received issues so improper.

Taubes disagreed that there was any reversal. The talk has simply  “transformed” from saturated fats as dangerous to impartial, he stated. However the difficulty is now: “neutral compared to what?”.

Saturated fats is meant to be “neutral” in comparison with carbohydrates however to not polyunsaturated fat (PUFAs) and vegetable oils. This suggests both that saturated fats is dangerous or that PUFAs and vegetable oils are useful.

Subsequently, the argument clearly hasn’t gone away”, he stated.

Harcombe has proven that there isn’t a strong proof to point out that changing saturated fats with PUFAs is a good suggestion.

Silence a greater choice?

Teicholz stated that the place robust proof was missing, it will be higher for specialists to “remain silent” than make misguided claims. She steered a means ahead:  the rules ought to include a brand new low-carb recommendation choice. That may keep away from modifications to different tips – and anybody having to confess to error.

In a convention evaluation, Harcombe famous that  “in any business strategy book, negotiation advice includes the principle “always give your opponent an out”. Teicholz’s suggestion does “exactly that”.

She has additionally stated that there’s little probability of the “mea culpa” that Godlee suggests may be in order ever materialising.

In an e mail to me, Willett stated that the classical diet-heart speculation is confirmed. And there are “layers of evidence” to help advantages of a largely plant-based weight loss plan (similar to a standard Mediterranean weight-reduction plan) versus a primarily animal-based weight-reduction plan, he stated.

The proof consists of superior results on blood lipids, long-term epidemiologic research and RCTs. These present “significant benefit of replacing saturated fat with PUFA that includes both N-6 and N-3 fatty acids”.

“All the evidence is in this direction, none in the opposite direction,” he stated.

For proof, he referred to his Dietary Epidemiology textbook, now in its third version.

“Replacing saturated fat with refined starch and sugar will not reduce risk of heart disease and could increase risk,” Willett stated. Alternative, subsequently, “is key”.

Meat and dairy fats not optimum?

On the core of a lot of dialogue, excessive dietary glycemic load is a “serious problem”, Willett stated. “However, it doesn’t mean that eating a lot of red meat and dairy fat is an optimal solution. There is a huge body of data of many types showing that it is not.”

He additionally described Ioannidis as “completely ignorant” in his presentation to the convention.

Ioannidis misrepresents how epidemiology is definitely carried out and the outcomes of research, Willett stated. “He makes his living by trashing other people’s work and has never done any serious research himself – the greatest COI (conflict of interest) of all.”

Prof David Diamond

US specialist Dr David Diamond watched the convention on live-streaming and shared his impressions with me by way of e mail.

Diamond is professor of psychology and molecular pharmacology and physiology on the College of South Florida. He has a private and professional curiosity in weight-reduction plan and heart problems. He misplaced weight and improved his triglycerides by chopping carbs and consuming butter, eggs and pink meat.

Diamond shares his information in on-line lectures, hospital “grand rounds” and invited lectures at worldwide medical conferences.

He delivered the keynote lecture on statins and coronary heart illness on the World Congress on Diabetes & Weight problems in Riga, Latvia in 2015. His lecture so impressed clinicians that they honoured him with their award for “outstanding contribution to science”.

Diamond has his share of detractors who help the diet-heart speculation. Right here’s his rebuttal to a heart specialist who stated his views on statins are “dangerous”.

Flaws in diet-heart speculation

Diamond described the diet-heart speculation as “flawed and antiquated”. Keys based mostly the simplicity of the speculation solely on his private beliefs, fairly than robust empirical science, he stated.

In a single research, Diamond and 16 co-authors (all MDs and/or PhDs, together with cardiologists) rigorously assessed the speculation that folks over the age of 60 with excessive ranges of LDL-C ( so-called “bad cholesterol”) would have a better price of demise from coronary heart illness and all-causes.

They discovered the other. Aged people with the very best ranges of LDL-C had an equal or, in most instances, a decrease price of demise, than these with the bottom ranges. That was one other stake in the diet-heart speculation.


Prof Jennie Model-Miller

Diamond was strongly crucial of College of Sydney vitamin professor Jenni Model-Miller’s presentation.

Model-Miller stated that processed meals had nice worth as a result of it made ladies’s lives simpler by “allowing them to go back to work”.

(Diamond wasn’t the one who discovered Model-Miller’s opinions astonishing and even primitive from a scientific perspective. She was fortunate to be chatting with a well-behaved viewers.)

Model-Miller additional claimed that a pregnant lady might hurt her rising foetus if she lowered her carbohydrate consumption.

New Zealand-based dietitian and educational Dr Caryn Zinn discovered that declare extraordinary, as Diamond and others discovered it.

‘Piffle quotient’

Diamond referred to as it “perhaps the (conference’s) worst scientific moment”. Model-Miller was “perhaps paid well by the food industry”, he stated – a sentiment that others on the convention echoed. She in all probability didn’t assist her crediblity a lot by additionally saying that we will’t blame the meals business for doing what we informed it to do: produce low-fat, high-carb meals.

Diamond stated that Model-Miller’s opinions represented a “piffle quotient”. It reached its highest degree when an MD in the viewers said that it was “well-known that the Atkins diet (with its reckless sanctioning of consumption of saturated fat) caused every form of disease known to Western civilization, including cancer, obesity and diabetes”.

Click on right here to learn: PHC lays low-fat diets to relaxation


Diamond paid tribute to Hallberg for responding to “this twaddle” by stating the apparent: Rigorously carried out analysis has proven that the Atkins weight-reduction plan has not been linked to those illnesses.

The coup de grâce for Diamond was criticism from a panel of Hallberg’s current Virta research displaying an enchancment of all main biomarkers of well being for diabetics and pre-diabetics with a really low-carb food plan in comparison with typical care.

Hallberg confirmed that a personalised (vegetarian or omnivorous) low-carb eating regimen could possibly be of nice worth. But panelists “obsessed over the fact that subjects could choose their own treatment option, rather than the study being sterilized with a random design”, Diamond stated.

He described Willett as “a force in the nutrition field by virtue of the fact that he’s a Harvard professor and has published a vast amount of (largely epidemiological) research to support his plant-based diet agenda”.

‘Weapons of mass cardiovascular destruction’

With regards to saturated fats, Willett considers beef and butter to be “weapons of mass cardiovascular destruction”, Diamond stated.

The convention gathering reminded him of his main space of analysis: one of the well-known, intense neuroscience debates. These concerned two nice neuroanatomists of the 19th century who had opposing views of the mind’s construction.

 Spanish anatomist Ramon y Cajal offered robust proof that mind cells have been distinctive and separate parts. Regardless of the overwhelming proof in favour of Cajal’s place, Italian anatomist Camillo Golgi believed that the mind was composed of a steady community of neural fibres.

Click on right here to learn: Saturated fats causes coronary heart illness? Bollocks – Kendrick

Once they shared a Nobel Prize for his or her analysis in 1906, the talk continued in their acceptance speeches. In it, every one stated he was proper and the opposite was improper.

Many years later, after each had died, the invention of the electron microscope ended the talk, Diamond stated. Pictures of particular person neurons unequivocally demonstrated that every mind cell was a separate factor bodily remoted from different cells. Subsequently, the proof proved Cajal proper, he says.

Golgi refused to simply accept overwhelming proof that his reticular concept of the mind was mistaken. Equally, Willett’s assertion that a plant-based weight-reduction plan is more healthy than a weight loss plan with animal fats is predicated on “a myopic approach that ignores or dismisses contrary findings”, Diamond stated.

The ‘Golgi’ of vitamin?

Willett will “prove to be the Camillo Golgi of the nutrition field”, he stated.

Vitamin science wants the equal of an electron microscope photograph to finish the talk on problems with saturated fats and the worth of the low-carbohydrate eating regimen as a diabetes and weight problems remedy.

“Ultimately, the equivalent of the decisive photograph in the nutrition field would be recognition that food that raises blood sugar, not consumption of meat, cheese, butter and eggs in large part cause the diseases of Western civilization,” Diamond stated.

From my vantage level, it was instructive to listen to an “eclectic” group (as Godlee described it ) of worldwide specialists supporting plant-based diets, giving proof and debating alongside animal-foods “enemies”. Harcombe famous in her evaluate that the convention was primarily a chance that allowed “some foes to become friends or at least acquaintances”.

Many, if not most, divisions disappeared over the past two convention days. Hallberg, medical director at Virta Well being, took centre stage to current her staff’s analysis. It’s the first clinically-proven remedy to point out that sort 2 diabetes actually is reversible safely and sustainably with out medicine or surgical procedure.

There have been no dissenting voices and rightly in order Hallberg did what good scientists do. She let the proof converse for itself.

She additionally dismissed the diet-heart speculation. The saturated fats debate is “over”, Hallberg stated. “We are pretty much done with it and we now need to get that message across.”

Hallberg additionally stated that low-carb is only one of three efficient choices to deal with and reverse sort 2 diabetes that embrace bariatric (abdomen) surgical procedure and caloric restriction.

No weight loss plan is one-size-fits-all and affected person selection “is key”, she stated.