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Rajiv Chowdhury

Fresh Insight into Saturated Fats and Nutrition

Dr Rajiv Chowdhury, Senior Research Associate in Global Cardiovascular Health at the University of Cambridge in England, is a qualified physician who was trained in Cardiovascular Epidemiology at the University of Cambridge with the support of a prestigious Gates Cambridge scholarship. Following completion of his PhD in 2013, he embarked on his current position of Senior Research Associate in Global Cardiovascular Health within this department. He was elected a Fellow of the UK Royal Society for Public Health in 2011.

In an interview, he addresses key issues in the debate on saturated fats and nutrition. He also expresses the need for public health practitioners to better inform consumers about the significant health risks associated with consuming trans fats.

1) Debate around nutrition is complex, including on saturated fats, sugar and carbohydrates. What do you feel are the key points that need to be addressed?

When it comes to the individual effect of fats, the principal reason why saturated fats have been considered harmful is their detrimental supplement effects on low-density (or bad) lipoprotein cholesterols in blood, observed in the earlier metabolic ward trials.

Nonetheless, these trials also reported that saturated fats tended to enhance high-density (or good) lipoprotein cholesterols and apo-A1, and reduce Lp(a) concentrations – all of which are potentially beneficial circumstances for coronary heart disease (CHD). Therefore, judging the effect of a nutrient on disease risk through its effect on a single intermediate factor may not be optimal.

It is also crucial to appreciate that the traditional crude grouping of fatty acids (such as ‘total’ saturated fats) is less helpful. This is because when specific fatty acid subtypes are examined, associations for these individual fats seem to vary significantly within each broad fatty acid family considered.

For example, recent evidence indicates that while odd-chain saturated fat subtypes (which correlate with dairy products) are beneficial for cardiometabolic health, even-chain saturated fat subtypes (which correlate with refined carbohydrates, sugary drinks and alcohol consumption, among others) tend to raise this risk. This suggests that food sources of specific fatty acid subtypes might be more important to determine subsequent disease susceptibility than any composite fatty acid group alone.

Finally, based on the available evidence from observational studies that assessed substitution effects of various nutrients, a key aspect to consider is what we are replacing the saturated fats with. It is often the case that when food manufacturers take out fats from food products, they replace those with carbohydrates from refined grain or sugar.

These refined carbohydrates get digested in our body rapidly, causing blood sugar and insulin levels to first rise and then dip, leading in turn to hunger, overeating and weight gain. Over time, these can enhance the risk of CHD. Therefore, when foods such as red or processed meats are reduced, they should perhaps be replaced with oily fish, nuts, beans and healthy oils.

2) There is an ongoing debate around the world about limiting trans fats. Do you feel there is an adequate understanding of the dangers of trans fats?

One of the key findings that we reported in our Annals of Internal Medicine review was a significant strong positive association of trans (or artificial) fats in diet with CHD risk (meta-analysing data from more than 150,000 participants from five long-term observational studies).

This is in line with the key nutritional guidelines that encourage avoidance of trans fats consumption. Eating trans fats raises bad cholesterols, reduces good cholesterols, and promotes inflammation and loss of optimal endothelial function in humans – all of which are cardiotoxic. Since there are absolutely no known requirements for trans fats for our body functions, the consumption of trans fats should be kept as minimal as possible.

While mandatory inclusion of the trans fats content in food labels has helped Western consumers to identify and avoid products with trans fats content, and encouraged many food manufacturers to reduce inclusion of trans fats in their products, I believe, however, that greater awareness worldwide is needed to inform members of the public and health practitioners about the significant health risks associated with consuming this artificial bad fat.

3) Palm oil is well-known as a replacement for trans fats in many foodstuffs. Is replacement of trans fats generally seen as a positive move by the scientific community?

There is little doubt, given the current evidence base, about the significant detrimental effect of trans fats on health, and the fact that this harmful artificial fat in food should be replaced by a healthier, natural alternative. Therefore, complete removal or replacement of trans fats from food products is definitely viewed as the right move forward.

However, when it comes to replacement, the scientific community appears to be somewhat divided on which alternative should be used to replace trans fats optimally. Natural choices such as palm oil are generally higher in even-chain saturated fat content than other plant oils. However, they seem to be less harmful than partially hydrogenated oil high in trans fats.

In dietary intervention studies, comparing a palm oil-rich diet with diets rich in trans fats yields significant higher levels of HDL cholesterol and apolipoprotein A-I, and significantly lower apolipoprotein B, triacylglycerols, and TC/HDL cholesterol.

4) Do you plan to conduct further research in this area, and what other questions do you feel need to be looked into?

There should be more research done to better understand individual and substitution effects of specific fat subtypes (and their food sources) on clinical cardiovascular outcomes, since the majority of previous work focused on intermediate factors (such as lipids).

This is also true for palm oil since the majority of studies that looked at palmitic acid (the predominant fatty acid in palm oil) in blood in relation to CHD generally included a few hundred coronary outcomes; were not optimally adjusted for wide range of potential dietary and non-dietary confounding factors; and none were carried out in non-Western populations (where levels of palm oil consumption is high).

Such studies are required to definitively answer which natural and healthier cooking oil is best suited to replace artificial trans fats for coronary disease reduction worldwide. We are currently working on several large-scale observational studies of incident CHD involving both Europeans and South Asians to answer some of these intriguing questions.

5) Would you be able to tell us a little more about these new studies, and when you would expect them to be published?

We are presently working on data from a large pan-European cohort and a large South-Asian cohort looking at specific fatty acids in relation to a large number of coronary disease outcomes. We expect preliminary results to be available potentially by middle of 2016.

MPOC

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Dr Guy-André Pelouze

Hazards of the ‘Low-fat’ Dogma

According to the World Health Organisation (WHO), obesity worldwide has more than doubled since 1980. In 2014, over 1.9 billion adults (18 years and older) were overweight – 600 million of them were obese.

That means 39% of adults aged 18 years and over were overweight in 2014, and 13% were obese. Furthermore, 42 million children under the age of 5 were overweight or obese in 2013.

Those figures and statistics are extremely worrisome. They take the obesity issue to a whole new level: obesity is an epidemic. As such, it should be considered a global emergency for many reasons, including:

  1. Most of the world’s population lives in countries where being overweight or obese is a substantial killer.
  1. The cost of these illnesses will be “astronomical”, as stated by Marion Nestle, who chairs the Department of Nutrition and Food Studies at New York University.

But, as is elegantly put in the summary of the fact sheet on the WHO website, ‘obesity is preventable’. The WHO goes on to explain the fundamental cause of obesity. Far from being unexpected, the assumption is that there is an energy imbalance between calories consumed and calories expended. Globally, there has been:

  • an increased intake of energy-dense foods that are high in fat; and
  • an increase in physical inactivity due to the increasingly sedentary nature of many forms of work, changing modes of transportation and increasing urbanisation.

 

Unfortunately, the answer to this global public health issue is not even close to helping patients. The WHO’s answer as to what causes the obesity epidemic is part of the reason why we inefficiently try to deal with it.

To me, it is very clear by now that the energy imbalance between calories consumed and calories expended is to blame. However, the concept of calories is most likely wrong and cannot explain obesity alone.

In this, the work of Dr Robert H Lustig (Professor of Paediatrics in the Division of Endocrinology; and Director of the Weight Assessment for Teen and Child Health Programme at University of California, San Francisco) is more than noteworthy.

But more importantly, WHO’s answer pointing towards fat as the main issue (‘increased intake of energy-dense foods that are high in fat’) needs to be reassessed. Evidence clearly shows that such foods are not solely responsible for the obesity epidemic. Fat alone cannot explain obesity.

Rising incidence of diabetes

According to the WHO, the number of people with diabetes has risen from 108 million in 1980 to 422 million in 2014. The global prevalence among adults over 18 years of age rose from 4.7% in 1980 to 8.5% in 2014 and has been rising more rapidly in middle- and low-income countries.

Diabetes is a major cause of heart attacks, stroke, blindness, kidney failure and lower limb amputation. One death every six seconds can be attributed to Type 2 diabetes.

Worldwide, approximately 1 in 10 adults has Type 2 diabetes mellitus. A significant fraction of the population has some degree of insulin resistance – approximately 40% in the US. The projection the WHO makes is that diabetes will be the seventh leading cause of death in 2030.

The incidence of diabetes is expanding extremely quickly and is a legitimate cause of worry. This is particularly because – as the WHO fact sheet reminds us – diabetes can be prevented or delayed with a healthy diet, regular physical activity, maintaining a normal body weight and avoiding tobacco use.

The WHO is actively promoting diabetes prevention and care management. There even is a World Diabetes Day. However, as surprising as it may seem, sugar is still not a definite target in the fight against diabetes.

Fat, sugar and prevention behaviour

With preventable diseases, patients can actually be part of the prevention behaviour. That is one of the most interesting aspects of nutrition as a field of study. Patients are in control of what food they purchase and consume. Provided they understand the consequences of their choices, they can be responsible. They need to understand the impact that the food they eat has on their health.

In previous papers and articles, we have shown that scientific evidence does not support the theory that was seen as the truth for so long. For ages, fat has been considered the cause of metabolic disease – but it obviously is not.

The fact that we have believed it for so long has led to room for concepts like that of Ancel Keys to grow and prosper. This destroyed perfectly good food habits that we used to have, leading to what we might now call the worst food epidemic ever known.

Those beliefs have driven us to take fat off our plates over time. That in itself is not the issue (although the body needs fat to work properly). But since fat and flavours are very closely related, fat-free or low-fat products were literally not edible. Neither were they satiable.

With close to no fat in our food, we had to find a solution; something to replace it in order to make food products palatable. And if that solution could be affordable, then the food industry would thrive.

Sugar was the answer everyone was looking for at the time. It replaced fat, made the food taste good and was inexpensive. It may even have been the easiest and cheapest solution at the time.

More importantly, it generated that strong positive reward in your brain – such a reaction in fact, that one can be addicted to sugar and crave it more and more.

Contrary to popular belief, fat does not make you fat; sugar does. The more sugar we ingest, the fatter we become. We then look for dietary solutions and end up consuming more low-fat, diet-food products. This adds to the problem by providing fewer fats and even more sugar to the body. All the sugar consumed stresses the pancreas; this, in turn, has an effect on insulin resistance.

The assumption that fat is unhealthy is therefore erroneous, as is the assumption that we consume too much of it. As a case in point, palm oil is a healthy source of lipids and vitamins, and is also free of trans fats. Yet, it has suffered a smear campaign over the last few years. As with many ‘low-fat’ products, we have found ‘palm oil-free’ products on shelves.

Fat in general, and palm oil in particular, is not – and never was – the culprit it was made out to be. Palm oil has a balanced composition that makes it one of the healthier options among oils and fats. Studies published over the last 10 years show precisely that we should not worry about palm oil, as it can be part of a balanced diet.

Sugar is not as easy to defend. Fructose – one of the dozens of forms of sugar – has always been present in fruit; but other kinds of sugar added to just about every food product have no particular metabolic benefit. Over-consumed, sugar does more harm than good. It promotes obesity and is responsible for diabetes, two epidemics that are among the leading causes of mortality.

Solutions at hand

Let me be straightforward: you should cut added sugars in order to reduce the amount consumed. But sugar is often hidden in food products; and since it has so many different names, it is difficult to identify. Low-fat products in particular, are riddled with hidden sugars.

We should move away from the low-fat dogma, and governments and regulators should absolutely support that shift. We should be looking to restore food habits we once had, where fat was considered healthy and sugar was not so frequently found in food. Those in charge of publishing dietary guidelines should recognise the scientific evidence supporting fat over sugar and take immediate action.

A healthy balance of fats should always be a key component of the diet. Palm oil is a prime example of this – it is good and healthy; and its balanced composition of saturated and unsaturated fat makes it also ideal for cooking.

Furthermore, it is very difficult to over-consume fat, as it is very satiating. Consuming fat in a low-carbohydrate diet also makes it easier for the body to access fat for energy.

Consumers are able to decide what they eat. However, they should be guided by the best available science. Moving away from added sugars and other carbohydrates, while adding more natural fats like palm oil, will rapidly improve health. It is time that regulators recognise, and endorse, this fact.

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Dr Guy-André Pelouze

Why Fatty Foods Do Not Have to Mean ‘Getting Fat’: An Explanation of Human Metabolism

It sounds intuitive: eat food-containing fat, and you will get fat. And yet it simply is not always true. For many people, this is very difficult to grasp, because this principle, this assertion is intuitive.  And as is usually the case, the intuitive always seems to override the actual facts.

Unfortunately, biology is not there to be simplistic.  It teaches us that it is not the fat that we eat that will be deposited in our arteries.  Indeed, there is no clear established link between the cholesterol that we eat, between the fat that we ingest and what gets deposited or not in our arteries.  Why?

Metabolic machine

It is actually quite easy to understand.  In between what we eat and our arteries, there is a massive metabolic machine to begin with.

The liver reconverts, reconfigures, and readjusts everything we eat after it has been digested by the digestive tract, in such a way that our needs are met. This metabolic machine makes little droplets in the bloodstream to transport fat towards peripheral tissues, in order to use it, produce energy, create membranes, produce hormones…  The liver regulates all this.

The liver as conductor

The second point that needs to be taken into consideration is that the liver is capable of transforming sugar into fat in a situation of surplus calories.  Now, what do we eat in great quantity today?  Starch: bread, pasta, wheat, corn, a certain number of cereals for breakfast etc.  All this represents much more than 50%, sometimes 60%, or even 80% of sugar, of carbohydrate. This is being discussed more and more, in dietary circles that the focus should not be on fats, but rather on sugar.
What does the liver do in the face of this situation of flooding?  It converts, slowly but surely, this carbohydrate into lipid, these little droplets that it then sends into the adipose tissue.  So much so that you can eat very little fat and nonetheless produce masses of triglycerides, that is fat, through the liver.  This is where lies the failure of all that is low-fat – that is light, without fat, without palm oil – because in reality, by substitution effect, we are often compelled to replace the fat by carbohydrate.

Low-fat is tasteless; because taste is often carried by fat.  Thus, to compensate for the lack of taste, we add carbohydrate, sugar. The body needs the intake of balanced fats that you can find in palm oil (50% saturated fats and 50% unsaturated) and substituting it with carbohydrates and sugar is not healthy for the body. It is a mistake to want to replace fats by carbohydrates or sugars that are real source of calories. This should be a warning: do not trust the foods where you read ‘no palm oil’ or ‘no fat’. It may sound enticing, but will not make you healthier. It is simply spin from the companies involved, without any science.

 

 

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Rajiv Chowdhury

Palm oil: Cambridge study, good alternative to bad fats

ROME – ”Palm oil can be considered as a healthier alternative to trans fats with its perfect balance of saturated and unsaturated fats and while maintaining reasonable shelf-life”, says Rajiv Chowdhury, associate professor in the department Global Cardiovascular Health of the University of Cambridge, who has published a research mentioned in a study just published by the National Obesity Forum, which reviewed the current UK dietary guidelines, acquitting precisely saturated fats.

” Our study, published in 2014, systematically combined results from all previously published observational studies, and found that a high intake of total saturated fat was not significantly associated with heart disease risk ”, says the professor, according to which it is not correct to speak of saturated fats as a whole; this because, coming from a wide range of foods, they vary as to their effects on health.
” For example  – explains the professor – saturated fats, which correlate strongly with foods high in carbohydrates and alcohol consumption, are associated with increased risk of diabetes and cardiovascular risk. By contrast, saturated fats, that correlate highly with dairy products, are associated with a reduced risk.”. As for the ideal diet, the watchword for Chowdhury, is balance. Yes and a combination of vegetables, fruits, whole grains and healthy proteins. ”Personally – the professor said – I prefer green, leafy vegetables, and sufficient amount of fruits in various colours;  Choose whole grains like whole-wheat bread and brown rice, avoid refine grains like white bread or white rice”.
As for proteins, those contained in fish, beans and nuts are optimal. Limit red meats and avoid processed meats. For milk and dairy products, one may wish to go for the natural whole-fat options given the recent growing evidence, in place of skimmed or semi skimmed products 1-2 servings/day. Finally, according to Dr Chowdhury, we should avoid trans fats, and limit salt consumption. Avoid having sugary drinks and alcohol. Drink water, tea or coffee, but with little or no sugar, and avoid artificial sweeteners.
Read article in ANSA
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Anne-Laure Meunier

Palm Oil Tax an Unhealthy Move

In early May, senators in the French Parlia­ment discussed a proposed Bill on biodiversity, nature and landscapes – commonly known as the Biodiversity Bill.

Although the text is lengthy, the Bill is still a clear demonstration of the common will of the French Parliament to put the debate on biodiversity on the right track. Like many others, I clearly support the stated intention of this Bill.

However, there is a critical part of the Bill that is directly linked to my professional expertise, and which is therefore puzzling to me.

As the parliamentary game of back-and-forth progressed, with discussions and amendments in both Houses, an additional tax on palm oil made its way into the National Assembly version of the Bill. This tax was put forward by MPs, based at least in part by allegations about palm oil’s effects on health.

For me, as a nutritionist, it is clear that the health allegations made against palm oil, voiced as justification for the tax, are nonsense.

It’s very important, first of all, to understand why palm oil is widely used in food products. The choice of a vegetable fat or vegetable oil by the food industry is often directly linked to the manufacturing and functional properties of a particular ingredient compared to competing oils or fats.

Food manufacturers that use palm oil as an ingredient do so for the same reasons, one of which is that palm oil has an important “technical” benefit compared to other vegetable oils – it is naturally semi-solid.

This means that palm oil can be added to food products without requiring partial hydrogenation – an industrial process that is instead needed to “harden” softer oils, and in so doing creating so-called “partially hydrogenated oils”.

Partially hydrogenated oils are very unhealthy, as they contain trans fatty acids (known as trans fats), whose harmful effects have been recognised unanimously by the scientific community.

Many countries have decided to ban trans fats in food products altogether, but neither France nor the European Union has taken any action thus far.

Palm oil, because of its natural state, does not require this industrial process of partial hydrogenation – and therefore palm oil never has trans fats. This is a major reason why the use of palm oil in food products has risen, not just in France, but also around the world.

Understanding this fact is fundamental to understanding why palm oil’s use is rising.

Palm oil is a healthy vegetable oil, naturally made up of 50% saturated and 50% unsaturated fatty acids. This balance, added to the total lack of trans fats, explains why palm oil is so popular and so widely used.

For some, this increase in palm oil use is seen as a problem. However, studies clearly show that French consumers actually consume very little palm oil.

It’s true that palm oil is found in many products, but it is present only in small quantities. This research has been conclusively published by the French agency for Food, Environmental and Occupational Health and Safety (Anses) in France.

The level of palm oil consumption, therefore, should not be a matter of concern at all. In fact, it seems that the palm oil tax is based on multiple, unfounded, fears.

If a tax is to be introduced – which is really not justifiable, especially when looking at the failed Danish experience with a “fat tax” – I believe it would be wiser to apply it to trans fats whose impact on public health is unde­­niable, and globally-recognised.

The problem with taxes based on fear and misunderstanding is that they can often have unintended negative consequences.

First, a tax on palm oil could lead to unhealthy alternatives – such as trans fats – being used in higher quantities in food in France. That is a bad outcome.

Second, a tax on palm oil would, as a direct result, raise prices for food products.

Yet we know that eating well is often a matter of available budget. The least fortunate families are also those that consume manufactured food products the most.

So, taxing palm oil will lead to higher prices for people buying food. That is also a very bad outcome.

As a nutritionist – not a politician – my message to the Members of the French Parliament is simple: when you evaluate this biodiversity bill project, take into account the harmful effects of your decision, both on public health and on the cost of living. The tax should be scrapped.

Read article in The Star

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Rajiv Chowdhury

What Do We Really Know About Saturated Fats?

A general argument often endorsed in the media suggests that intake of any saturated fat should be reduced due to potential links to high risks of coronary heart disease (CHD).

In an interview with Global Oils & Fats Business Magazine, University of Cambridge, United Kingdom, Global Cardiovascular Health senior research associate Dr Rajiv Chowdhury discusses his latest findings on saturated fats and cardiovascular disease, and the new debate on fats and nutrition.

He explains his views on these broad assumptions that were based on somewhat inconsistent evidence.

He also expresses the need for public health practitioners to better inform consumers about the significant health risks associated with consuming trans fats.

Your study, published in the Annals of Internal Medicine, generated a lot of interest. Can you explain the findings of the study?

Our meta-analysis, published in March 2014, investigated how fatty acids consumption or circulating composition might be related to future risk of CHD.

According to Dr Rajiv, the meta-analysis found no significant association for total or composite saturated fats in the diet with the risk of heart disease.
According to Dr Rajiv, the meta-analysis found no significant association for total or composite saturated fats in the diet with the risk of heart disease.

In our analyses, we included estimates from observational studies that measured “total” fatty acids from dietary intake; observational biomarkers studies that looked at “individual” fatty acid subtypes; and randomised controlled trials of fatty acid supplementation.

Taken together, this quantitative review combined data from 72 unique studies involving over 600,000 participants from approximately 20 countries.

First, we considered results on dietary total fatty acid intake from 32 prospective studies (with 512,420 participants).

We found essentially nil associations for total saturated, monounsaturated and omega-6 polyunsaturated fatty acids with CHD, whereas intake of long-chain omega-3 polyunsaturated fatty acids was associated with lower CHD risk, and intake of trans fatty acids was associated with higher CHD risk.

Second, we considered results on individual circulating fatty acid subtypes from 17 prospective biomarker studies (with 25,721 participants).

We found a significant inverse association between margaric acid and CHD, and non-significant positive associations of palmitic and stearic acids with CHD.

We found some evidence that circulating levels of eicosapentaenoic and docosahexaenoic acid (the two main types of long-chain omega-3), and arachidonic acid, were each associated with lower CHD risk.

Third, we considered 27 randomised controlled trials of fatty acid supplementation or replacement (with 105,085 participants).

In aggregate, these trials have not suggested clear benefits after supplementation with alpha-linolenic acid or with long-chain omega-3 fatty acid, or replacement of saturated fats with omega-6 polyunsaturated fatty acid.

Real full interview here

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Dr Guy-André Pelouze

Myth and Fat: How One Inaccurate Hypothesis Mislead Public Health Policies for Generations

Dr Ancel Keys (Jan 26, 1904–Nov 20, 2004) was an American scientist who studied the influence of diet on health. He is responsible, almost more than any other individual, for the public health misconception around fats that exists today. Through published work that was vaunted across the world, Dr Keys has had a far-reaching impact on how we think about the role of fats.

When Dr Keys first published his theories, alleging that saturated fats were uniquely harmful, they were controversial. This controversy remains strong today as the debate on the roles of fat and sugar in relation to cardiovascular disease (CVD) associated with atheroma (the fatty material that forms plaques in arteries) goes on.

This article reflects upon two main subjects: understanding the complexity of chronic diseases as the antithesis of acute infectious diseases; and the principle of falsifiability applied to atheroma theories and the practical consequences this entails.

After World War II, the work of Dr Keys played a fundamental role in the debate around fats. How?

Because it claimed to demonstrate a link between saturated fats consumption and atheroma: “Many factors are probably involved in the atherosclerotic development and in the clinical appearance of coronary heart disease, but there is no longer any doubt that one central item is the concentration, over time, of cholesterol and related lipids and lipoproteins in the blood serum. No other etiological (sic) influence of comparable importance is as yet identified.” ( A. Keys, American Journal of Public Health, Nov 1953, vol 43, 1399-1407.)

Today, in reality, scientists see tobacco, diabetes and hypertension to be much more powerful risk factors. We condemn researchers who, for over 40 years, have not been keen to verify the data and the conclusions it suggested.

Epidemiology in modern history

Epidemiologic observations have drawn the attention of scientists for a long time on the link between dietary change and cardiovascular diseases. Examples of populations with low CVD prevalence or populations where CVD are the first cause of mortality have led epidemiologists to do research on food.

This is what we called the DietHeart Hypothesis. But it is so incredibly complex that even till today, we have yet to come up with a definitive answer. Simple hypotheses (i.e. single-factor cause) and invalid experimental models have produced abundant literature, of which little is actually helpful.

We can, however, wonder about the recent dietary changes brought by the recent industrial transition. In the West, those changes can be qualified with three factors:

  • Abundance of calories
  • Abundance of carbohydrates
  • Abundance of processed foods

Further to these, we should not forget about calorie expenditure. In industrialised countries, we have shifted to a sedentary lifestyle (at work, in public transportation or for personal activities).

Dr Keys supported his hypothesis with charisma. How is that possible? He and his team set out to study the dietary characteristics and lifestyles of different populations worldwide and compare the prevalence of coronary diseases. It was a rather large study at the time and needed significant funding.

This study addressed the issue of the heart attack epidemic that was hitting the United States and other developed countries at the time. He quickly focused on diet-related risk factors, mostly because they were easier to measure, particularly through blood levels.

Among macronutrients, Dr Keys had already explored fat and the indirect measure of blood lipids via blood cholesterol.

The study would be published in a book in 1980 ( Seven Countries. A multivariate analysis of death and coronary heart disease).

In the meantime, Dr Keys got more famous, was interviewed often, and in January 1961, was on the cover of Time Magazine.

Dr Keys described a link in the studied cohorts between the percentage of saturated fats in the diet and the death rate by coronary events. The correlation was dependent on the number of countries studied, but it was significant in the cohorts he chose.

As there was a correlation between total blood cholesterol and the same events, and as Dr Keys highlighted that saturated fats (especially palmitic acid as it is the most common) increased blood cholesterol, a conclusion appeared.

He stated that saturated fats, including palmitic acid, were linked to coronary atheroma. Others have then bridged the gap, saying they cause coronary diseases.

Obviously, all of this was not true. Inaccuracies and biases made his observations invalid.

Even Dr Keys ended up publishing more balanced conclusions than others: “Our 10 year finding, and concordance with other studies, make it clear that the big three risk factors for coronary heart disease now established are age, blood pressure, and serum cholesterol. The findings about cigarette smoking as a risk factor indicate that here, too, relationships are not as simple as first supposed.” ( Seven Countries, page 341).

He later became an advocate of the Mediterranean diet and kept studying it for a while. In 1975, he published How to Eat Well and Stay Well the Mediterranean Way.

Consequences still felt today

Dietary guidelines from experts and governments have been largely based on Dr Keys’ work.

To lower our intake in cholesterol and saturated fats, populations have massively consumed food products in which fats have been replaced with carbohydrates, and saturated fats with vegetable oils rich in omega-6.

This did not change the prevalence of atheroma-related diseases. New research even shows these changes may be linked to the obesity epidemic and type 2 diabetes.

Palm oil for one, which has a good balance between saturated and unsaturated fats, constitutes a healthy alternative – but it has been unjustly maligned for containing saturated fats.

There have been economic consequences too. This is linked to the food industry’s ability to quickly find a new market opportunity with low-fat food products. It has, as always, been shown to be very innovative in that regard.

Its lobby was powerful and the “low-fat” concept developed globally even though it is not possible as of yet to show it has any positive impact of cardiovascular health.

In the 40 years between Dr Keys’ work and the shadow cast upon it, many scientific articles have been published to try and explain the anomalies observed in real populations.

None ever questioned what had become a dogma. The different paradoxes, including the famous French Paradox, have only started to shake the foundation of his hypothesis.

Who bears the responsibility?

Surely, Dr Keys cannot be held responsible for how his data was used.

But his vision clearly influenced medicine for generations and overstated the importance of saturated fats and cholesterol in cardiovascular risk.

A summary of the Seven Countries Study on the University of Minnesota, US (where the study was coordinated), website, had this to say: “The main implications of the Seven Countries Study are that the mass burden and epidemic of atherosclerotic diseases has cultural origins, is preventable, can change rapidly, and is strongly influenced by the fatty composition of the habitual diet.

“The study implies the universal susceptibility of humans to CVD, but that the frequency of susceptible phenotypes is greatly reduced in favourable environments. It suggests there may be other and important protective elements in the diet and lifestyles of Crete and Japan.”

The only concession made to Dr Keys’ theories is the confirmation of a strong influence of the composition of lipids in the diet, but the words “saturated fats” are no longer used.

The Journal of the American College of Cardiology recently reminded physicians:“Atherosclerosis is a multifactorial disease and requires a multifactorial approach with smoking cessation, dietary modification and weight management, regular physical activity, attention to psychosocial risk factors, and pharmacological therapy of lipid and nonlipid risk factors.

“Comprehensive risk factor control is associated with improved prognosis, and our challenge is to develop care models that will allow us to achieve such control.”

We need to keep in mind that tobacco, type 2 diabetes and hypertension are, in that order, more powerful atheroma risk factors than LDL particles. There is no interest in dietary cholesterol in preventing CVD.

Saturated fats, like monounsaturated fats, and like carbohydrates, increase the amount of LDL particles when in calorie excess and promotes atheroma if other risk factors are present, and if phenotype is susceptible.

This is the reason why we cannot predict among high-LDL patients those who will have a cardiovascular, cerebral or peripheral event, other than watching the three aforementioned powerful risk factors, or having proper atheroma plaques exams.

In summary, Dr Keys was wrong, and his mistake has been compounded over the decades. It is time now to end the crusade against saturated fats.

The Star Malaysia 24 Apr 2016

Categories
Anne-Laure Meunier

European Parliament Recommends Removing Trans Fats in Europe

Contrepoints – EU report shows that using palm oil can help improve health outcomes in Europe.

The European Parliament’s research service has published an important contribution to the European debate around trans fats. The Parliament’s eight-page document is currently on its website and anyone can clearly understand from reading it, what trans fats are and the impact they have today on public health.

The European Parliament’s document essentially reaches three primary conclusions – first, that trans fats are agreed by consensus to be uniquely harmful; second, that they can be replaced easily and beneficially with currently available natural products, such as palm oil; and third, that the EU needs to step up work on this areas as to date only four countries in the EU have actually taken sufficient action against trans fats.

The European Parliament’s conclusions show that on this subject, the whole scientific community has reached a consensus: industrial trans fats, created from partial hydrogenation of fluid oils, significantly increase the risk of cardiovascular disease, obesity and type 2 diabetes. They also argue that we would collectively benefit from promoting the limitation of consumption – or even a complete ban – and use alternative fats instead, such as certain transformed unsaturated oils, animal fats such as butter, and of course vegetable oils naturally rich in saturated fatty acids.. Palm oil for example, as highlighted by the Parliamentary research service, is already widely used around the world as a natural replacement for trans fats.

Trans fats targeted by organisations worldwide

If there is a globally accepted truth, it is that trans fatty acids are a health hazard that must be addressed. In fact, cardiovascular disease is the leading cause of death in Europe and WHO warns that consumption of about 2% of daily energy intake increases by 23% the risk of a cardiovascular event. In response, health authorities have resolved to take action. In 2015, the Food and Drug Administration of the USA issued a decision stipulating that trans fats were not recognised as generally safe for human consumption anymore. Denmark was the first member country of the EU in 2003 to limit the amount of trans fat in a product, setting the 2% of total fat objective. The question is, why are other countries – and the EU itself – not following these pioneers?

Why do we still find these fats in our food?

The answer is uncertain. What is certain however is that trans fats were brought in during the 1950s as an alternative to animal fats. It was believed that the content of saturated fat in animal products made them less healthy. This advice, which led to the reduction of saturated fat consumption and the rise of trans fat consumption, has been shown to be a colossal mistake. In retrospect, such irony. But the functional properties of partially hydrogenated oils made them very popular with agribusiness companies.

Choosing healthy alternatives

With results as significant as those observed in Denmark, where a recent study showed that cardiovascular health improved more quickly after the measures against trans fats were taken, compared to that of the average in OECD countries, Europe must take the matter in its own hands. For ten years now, many European countries have opted for a restriction of the use of partially hydrogenated oils, pushing towards healthy, natural fats. These include palm oil, which is an entirely rational choice, though often unfairly demonised in the media. Naturally semi-solid at room temperature, it requires no transformation or hydrogenation to be usable by the industry. Its functional properties give it a clear advantage over other less saturated oils, which must be processed. In addition, it contains absolutely no GMOs.

Moreover, and this is probably the most important point, any effort towards the reduction (or elimination) of the consumption of trans fats is a step in the right direction. Several serious studies were able to show that substituting it with saturated or unsaturated fatty acids in human diet represented significant progress.

As for the still-active debate about the impact of saturated fatty acids on health, this is an outdated 50-year old dogma, which is contradicted by dozens of studies. Even for those laggards who have not quite accepted this new paradigm, one certainty remains: unlike saturated fats, trans fats are unanimously recognised as dangerous. The European Parliament’s report is welcome: it needs to be not just words, but a spur to action for all of us across Europe.

https://www.contrepoints.org/2016/04/02/245264-lue-recommande-de-remplacer-les-graisses-trans

 

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Authors Dr Guy-André Pelouze

Fats and Mortality: Beginning of the End of a Myth

The conventional wisdom that saturated fats are problematic for human nutrition is simply not credible any more, in the face of increasing scientific evidence. The latest evidence comes from De Souza et al, who have published in the British Medical Journal (http://www.bmj.com/content/351/bmj.h3978) looking into saturated fat consumption. I will examine the scientific details in this blogpost – but the important headline is that we, as medical professionals, media, society, need to challenge the previously assumed link between saturated fats and CVD. The evidence now shows that the old advice was wrong.

Palm oil is one saturated fat that has suffered from this misperception: my hope is that the more evidence emerges, the more difficult it will be for anti-palm oil activists to persist with their erroneous negative claims.

Saturated fat consumption, scientific interest and political issues

Fat consumption has been scrutinised by researchers and government agencies since the aftermath of World War 2. This is mainly the consequence of the lipid heart hypothesis formulated by the scientist Ancel Keys, in the 1950s, which was never confirmed but has passed into dietary guidance ever since. This study suffered all the bias of retrospective or prospective non-interventional epidemiological studies about diet and CVD. Particular weaknesses include –

  • Very poor quality of diet analysis and questionnaires
  • No control group and a lot of confounding parameters
  • Weak correlations and very low absolute risk differences
  • Wide range of metabolic responses among individuals to intake of carbs / lipids / proteins
  • Ignorance of the type of fat and especially the amount of industrially produced trans fats
  • Selection of countries and/ or avoidance of those with high intake of saturated fats and low CVD rates like France or Spain.

To illustrate this, let me review the selection process of the studies as shown in Figure 1 of the paper (http://www.bmj.com/content/351/bmj.h3978). THE BMJ paper finds that os much of the literature on saturated fats following Ancel Keys was not of sufficient scientific quality. From 20,413 studies in the database, only 41 were selected (because of lack of information, low quality, and other insufficiencies). For instance, from the 445 studies resulting of a process of eligibility based on the full text, 372 were excluded because:

  • They did not assess saturated fat exposure
  • They did not measure outcomes of interest
  • They duplicate data from previous publications
  • They did not present a measure of associations
  • They have an inappropriate study design.

There is more, the GRADE (http://www.gradeworkinggroup.org/index.htm) evidence profile of quality is very low for all the comparisons done in the selected studies in the past around saturated fats, as found yb the BMJ (http://www.bmj.com/content/bmj/suppl/2015/08/11/bmj.h3978.DC1/sour025275.ww5_default.pdf).

What are the findings?

Once more, I have to insist on a critical point in human observational studies about diet: mortality is crucial. Without any effect on mortality, observational studies should be taken with extreme precautions for further conclusions. Figure 2, which is displayed below, illustrates very precisely how saturated fat are neutral on different risks and the great heterogeneity of studies on CHD and saturated fats.

 

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Recently the number of papers by nutrition specialists who doubt or challenge results of studies about saturated fats and CVD has increased because the statistical reality as assessed by meta-analysis or recalculating old data is indeed against any detrimental effect of saturated fats on cardiovascular health.

Atheroma and CVD are complex issues, which are not caused by fat (or cholesterol) in your plate, and therefore not caused by palm oil.

Without a doubt, we are near the end of a myth. The only surprise is the slowness of the process i.e. the extraordinary conservatism of the scientific community about the diet heart hypothesis. No doubt that economic interests (the low-fat industry, the sugar industry and at large the agro-food industry) and the traditional reluctance to change of highly centralised bureaucracy are key explanations for exceptional lasting of this myth. But enough is enough because this advice is not neutral and even deleterious to populations following it and consequently do not engage in actual and efficient prevention of CVD.

 

Categories
Authors Dr Guy-André Pelouze

Palm Oil is an Excellent Cooking Oil: Heat-Resistant and Healthy

In an article published recently, The UK Daily Telegraph journalist Robert Mendick wrote about how vegetable oils become toxic when heated, because they release “toxic cancer-causing chemicals”. In this article, five different fats are compared: two saturated fats (coconut oil and butter) and three vegetable, highly-unsaturated oils (extra virgin olive oil, corn and sunflower oil).

It is indeed true that not all fats are equal. It is also true that no fat is perfect. What is important to understand is that some fats, whether animal fat or vegetable oil, are good when used cold, in salad dressings or marinades for instance; while others are better suited for cooking, sautéing or frying. Heat can be harsh on some fats, especially vegetable oils, as was stated on The Telegraph article.

 

Vegetable oil doesn’t mean unsaturated fat

The journalist compared vegetable oils often considered healthy (corn, sunflower) to other fats rich in saturated fatty acids, such as coconut oil or butter. Saturated oils and fats are more stable when heat is applied. Therefore, as shown by the study quoted in the article, they are a healthier alternative when it comes to cooking. So coconut oil is ideal, as it contains roughly 85% of saturated fatty acids, so is butter with 65% saturated fatty acids.

What is odd, though, is that palm oil is not mentioned. With a balanced composition (50% saturated and 50% unsaturated), palm oil is perfect for cooking, even frying, as it is very heat-resistant. It doesn’t break down or mutate when used for frying. It is also naturally trans-fat free and cholesterol free.

 

Healthy, balanced alternative

A truly accurate article would have established palm oil as one of the best alternatives to corn or sunflower oil for cooking. Palm oil’s excellent heat resistance and balanced composition make it one of the healthier options available.

Education about food and cooking is essential if Europeans are to improve their diets and overall health outcomes. Using palm oil as a cooking oil, in place of the potentially-hazardous unsaturated oils (sunflower, corn) is a prime example of this.