Lipids (4) – Should we stop consuming saturated fat?
“Why are my older patients, after a lifetime of eating eggs, meat and butter, in excellent health?”
Dr. Kate Shanahan
Among other things, saturated fat is essential for the integrity and function of the brain and cell membrane, great source of energy, antiviral, helps in the absorption of minerals, is a carrier of fat-soluble vitamins, in the absence of carbohydrates it is a cleaner fuel because it generates less oxidation in its combustion, protects the liver, is fuel for the brain (ketone bodies), is essential for a wide variety of hormones, and is the heart’s preferred fuel (1).
Meanwhile, the studies against it are weak (2). In fact, the studies cited by the American Heart Association, were highly questioned by the journalist, Gary Taubes, who stated…
“They have many flaws and the information has been collected in a very convenient way“
Gary Taubes is an investigative journalist that has spent the last 3 decades covering controversial scientific topics.
In the early 1990s, he wrote Bad Science, a book on the controversial science behind cold fusion. But his interest in the difference between evidence and “the interpretation of the evidence” had only just begun.
According to Taubes (3), his acquaintances in the area of physics told him that if he was interested in bad science, he should investigate the area of public health … and he did.
After a few years of research, in 2002 he wrote an article for the New York Times magazine called What if It’s All Been a Big Fat Lie? (4).
The article has that title as a play on words, hinting at how dietary recommendations have led to an obesity epidemic.
This article had an international impact and became a more in-depth investigation of the medical science establishment, prompting Taubes to publish the books, Good Calories, Bad Calories and Why We Get Fat: and What To Do About It. Books in which he talked about how scientists fool themselves into believing what they want the results of their studies to be, and not what the results actually show…
“When Ancel Keys presented the study of the 7 countries, they automatically put America on a diet low in saturated fat”
“It’s good to have a hypothesis, but then you have to prove it with science. When this myth arose, they did a dozen studies that cost around $ 250 million trying to prove these theories, in which they failed miserably and have never been able to show that you can prolong life by reducing saturated fat … and what was the response of the authorities? … that such studies must be badly done“
“The best way to do bad science is to take the information that supports your theory and discard the information that does not.“
Gary Taubes
So, what does science say?
Not only have there been dozens of studies between 1960 and 1975, but many have continued to this day and the lipid hypothesis has never been proven, which is why more than six decades later, it is still called a hypothesis.
“Numerous meta-analyses and systematic reviews of both the historical and current literature, reveals that the diet-heart hypothesis was not, and still is not, supported by the evidence. There appears to be no consistent benefit to all-cause or CVD mortality from the reduction of dietary saturated fat. Further, saturated fat has been shown in some cases to have an inverse relationship with obesity-related type 2 diabetes. Rather than focus on a single nutrient, the overall diet quality and elimination of processed foods, including simple carbohydrates, would likely do more to improve CVD and overall health. It is in the best interest of the American public to clarify dietary guidelines to recognize that dietary saturated fat is not the villain we once thought it was.”
Saturated Fat: Part of a Healthy Diet (2)
More studies:
- In a large review (5) based on 32 observational studies on dietary fatty acids (512,420 participants), 17 observational studies of fatty acid biomarkers (25,721 participants) and 27 randomized controlled trials of fatty acid supplementation (105,085 participants), the conclusion was …
“Current evidence does not support the recommendations of a high consumption of polyunsaturated fatty acids and a low consumption of total saturated fat“
- In 2016, a very comprehensive study came to light that was done more than 40 years before (6) and was never published.
In this double-blind control trial, the idea that vegetable oils are better for health than saturated fats was completely challenged.
After one year, the group that consumed vegetable oils had a 14% decrease in cholesterol, but this translated into worse health. For every 30 percentage points of total cholesterol that dropped, all-cause mortality increased by 22%, and for people over 65 years of age in this group, there were 15% more deaths and twice as many heart attacks.
- In the Sydney heart study review, consuming polyunsaturated fatty acids instead of saturated fats, increased rates of all-cause mortality, coronary heart disease, and cardiovascular disease (7).
- A meta-analysis of 21 studies including nearly 350,000 participants found no difference between people with higher or lower saturated fat consumption when it comes to cardiovascular risk or stroke (8).
- In a study in humans, supplementation with saturated fatty acids (stearic acid) fueled a process called mitochondrial fusion and made mitochondria more efficient at using fat for energy (9).
- In mice, supplementation with saturated fat high in stearic acid reduced the toxic effects of ethanol consumption on the liver (10).
- A 22-year study of saturated fat in dairy found no difference between people who ate large or small amounts (11).
- The studies on coconut oil with negative results were made with partially hydrogenated and refined oil, and not with the extra virgin, which leads to very different results. In fact, coconut oil has been shown to raise HDL without affecting LDL (12), which is considered very positive when it comes to heart disease even by the standards.
- When in a breast cancer metastasis model the mice were fed a diet enriched with saturated fatty acids (stearic acid), safflower oil (linoleic acid), corn oil (oleic acid) or a diet low in fat ad libitum. The result was that visceral fat was reduced by approximately 70% in the group fed saturated fatty acids (13).
- Cell composition analysis showed that women with larger adipocytes have a lower content of saturated fatty acids in these cells (14).
What does evolution tell us?
Recent research from Tel Aviv University in collaboration with Portugal’s Minho University (15), studying the nutrition of Stone Age humans, present very strong evidence that the species passed about 2 million years as hypercarnivorous “apex predators”, feeding mainly on meat from large animals…
“We propose a picture that is unprecedented in its inclusiveness and breadth, which clearly shows that humans were initially apex predators, who specialized in hunting large animals”
“It is hard to convince a devout vegetarian that his/her ancestors were not vegetarians, and people tend to confuse personal beliefs with scientific reality. Our study is both multidisciplinary and interdisciplinary”
Dr. Ran Barkai (16)
“Human behavior changes rapidly, but evolution is slow. The body remembers”
Dr Miki Ben-Dor (16)
A cow, for example, has four stomachs full of bacteria that are capable of digesting any type of plant component; while on the contrary, the stomach of a carnivorous animal is extremely acidic and inhospitable to microorganisms.
The acidity of our stomach is high even for predators…
“Producing and maintaining strong acidity require large amounts of energy, and its existence is evidence for consuming animal products”
“Strong acidity provides protection from harmful bacteria found in meat, and prehistoric humans, hunting large animals whose meat sufficed for days or even weeks, often consumed old meat containing large quantities of bacteria, and thus needed to maintain a high level of acidity”
Dr. Miki Ben-Dor (17)
The researchers also highlighted that the structure of fat in human cells is similar to that of predators, stored in a large number of small adipocytes, whereas in omnivores, it tends to be the other way around.
“Geneticists have concluded that ‘areas of the human genome were closed off to enable a fat-rich diet, while in chimpanzees, areas of the genome were opened to enable a sugar-rich diet”
Dr Miki Ben-Dor(17)
To all this evidence, they’ve also added the study of stable isotopes in the bones of prehistoric humans, which point to the consumption of meat with a high fat content.
Most of the studies on the diet of ancient humans have been based mainly on the observation of hunter-gatherer societies of the last centuries; therefore, they do not reflect the availability of larger animals. Even so, many agrarian tribes still existing that before the introduction of the Western diet were unaware of cognitive diseases, coronary heart disease or diabetes, had (and some still have) a diet high in saturated fat for millennia (40 to 70% of total calories) such as the Masai, Hadza, Rendille, Tokelau or Inuit tribes.
In these societies, the consumption of saturated fats was accompanied by a moderate to low carbohydrate intake and lacking in refined sugars, processed foods or vegetable seed oils. But in our society, this changes radically.
Epidemiological studies do not provide reliable information:
Have you ever heard that “there are studies” that “show” that carnivores live less or have worse health? …
For decades the population has been convinced that saturated fats were harmful, therefore, those who were not concerned about consuming these fats were usually individuals with unhealthy habits.
These studies that suggest that a high consumption of meat is related to higher mortality are not interventional studies, but epidemiological … that is, they are based on statistics (what people report eating) and without any type of double-blind control.
Do you have a friend who has decided to eat a vegetarian diet, started doing meditation, exercise and quit smoking? Have you noticed that these changes always come hand in hand?
This is exactly why when it comes to nutrition, epidemiological studies are inaccurate.
In these types of statistics, the carnivorous population is basically “the standard” of the Western diet, while the vegetarian population is usually people who try to do something for their health.
These epidemiological studies generally do not take into account whether the participants are smokers, have a sedentary lifestyle or worse, from which foods these saturated fats are obtained since in this context, in the group of “carnivores” there is usually a high consumption of fast foods, processed, deprived of nutrients and rich in sugars, refined carbohydrates and oxidized polyunsaturated fatty acids, components that, unlike saturated fat, have proven to seriously affect health.
The only way to have a more solid reference is to do a controlled study in a group that consumes high amounts of saturated fat in a healthy context and where each piece of food is taken into account.
Although there aren’t practically such studies, in one of the few studies that was done in a controlled environment (6) comparing saturated fats with vegetable oils, those who consumed vegetable oils had more heart attacks and deaths.
On the other hand, and even if it cannot be considered “scientific evidence” according to the standards, in all the forums of low carbohydrates diets (ketogenic, paleo, carnivorous) anywhere in the world, where 50 to 80% of calories are obtained from fat, most people report marked improvements in many aspects of health.
This type of group would be more appropriate if you want to do an epidemiological study on the impact of meat and saturated fats on health, since it would be the equivalent of vegetarians, that is, people who have introduced dietary changes in the lifestyle to improve your health.
Could we have prevented the epidemic of metabolic diseases of the last decades?
- Since the 1950s Dr Fred Kummerow has been warning the authorities about the dangers of trans fats (18) and in fact, when the FDA finally decided to ban them in 2013, Dr Kummerow, with almost 100 years old, sued them for the delay (19).
- When the study of the seven countries was published, Dr. John Yudkin of the University of London found that the countries indicated by Keys were exactly the ones with the highest sugar consumption, but as we already know, this relationship was not mentioned and Dr. Yudkin, was publicly ridiculed.
- For decades, lipid scientist Dr. Gerhard Spiteller has shown that processed polyunsaturated fatty acids are the ones that affect the arteries.
- Another voice, which like many others who tried to warn of the dangers of these lipids was ignored, was that of the brilliant scientist Dr. Mary Enig, another lipid scientist.
- In 2001, nutrition scientists met at the Harvard School of Public Health (20), where it was argued that this “low-fat, anti-cholesterol” campaign has not only not done much for health, but could have aggravated the problem. These scientists suggested that the campaign was based on miniscule evidence and that it could have caused health consequences (unintentionally).
(TakeAway and Conclusions:
- When a hypothesis comes up, then you have to test it. In Keys’s graph, both sugar and saturated fat showed a relationship with heart disease, but years of research have failed to show that restricting saturated fat improves health in any way, while as we have already seen, refined sugar has proven to have harmful effects on health for decades and its restriction has proven to radically improve it.
- Saturated fats provide a large number of benefits; reducing them has not proven to prolong life and on the contrary, replacing them with certain vegetable oils has proven to shorten it.
- This hypothesis grew only out of interest and never had the intention of protecting public health.
- The first step of science is observation. In any forum in the world, where thousands of users share their experience with low carb diets in general (Paleo, ketogenic, carnivorous etc.), the vast majority reported only benefits.
- In my personal experience, both in my own health and that of my clients, eliminating refined carbohydrates and vegetable seed oils while maintaining a good consumption of natural fats, has marked a before and after in innumerable aspects)
In the next blog we are going to talk about one of the most controversial molecules…cholesterol.
References:
1 – Section 30.2 Each Organ Has a Unique Metabolic Profile.
2 – Saturated Fat: Part of a Healthy Diet.
4 – What if It’s All Been a Big Fat Lie?
9 – Dietary stearic acid regulates mitochondria in vivo in humans
13 – Dietary Stearic Acid Leads to a Reduction of Visceral Adipose Tissue in Athymic Nude Mice
14 – Stearic acid content of abdominal adipose tissues in obese women
15 – The evolution of the human trophic level during the Pleistocene.
16 – For 2 million years, humans ate meat and little else — study.
17 – Israeli study: Humans were hyper-carnivorous apex predators for 2 million years.
18 – Hydrogenation. Trans fats. Dietary cholesterol Fred Kummerow’s double victory.
19 – Entrevista a Fred Kummerow.
20 – Types of dietary fat and risk of coronary heart disease: a critical review.