Saturated Fat Is
Good For You
by Uffe Ravnskov
Saturated fat is the
type of fat that dominates in animal food such as eggs, cream, meat
and cheese and is also abundant in palm and coconut oil. Today many
of our scientists consider too much saturated fat just as dangerous
to our arteries as are greasy food leftovers for the drains of our
kitchen sink. Since only 10,000 years ago, as hunter-gatherers, our
paleolithic diet cotained abundant saturated fat, other scientists
For several years
sceptical scientists including myself have asked the experts on the
Swedish National Food
Administration after the
scientific studies that allow them to warn against saturated fat.
Their usual answer have been that “there are thousands of such
studies”, or they refer to the WHO guidelines,1
said to have been written by the world’s greatest experts.
The main argument in
that document is that saturated fat raises cholesterol, but we now
know that high cholesterol is not a disease. What we want to know is
if we shorten our life or if we run a greater risk of getting a
heart attack or a stroke by eating too much saturated fat.
Recently the Swedish
Food Administration published a list of 72 studies that they claimed
were in support of their warnings. Together with eleven colleagues I
scrutinized the list and found was that only two of them were in
Eleven studies did not
concern saturated fat at all.
Sixteen studies were
about saturated fat, but were not in support.
Three reviews had
ignored all contradictory studies.
Eleven studies gave
partially or doubtful support.
Eight studies concerned
reviews of experiments where the treatment included not only a
“healthy” diet, but also weight reduction, smoking cessation and
physical exercise. So how did they know whether the small effect was
due to less saturated fat or to something else? Furthermore, all of
them had excluded trials with a negative outcome.
Twenty-one studies were
about surrogate outcomes. In most of the reports the authors claimed
that saturated fat raises cholesterol. But again, high cholesterol
is not a disease.
Twelve studies were
listed because they had shown that people on a diet with much
saturated fat and little carbohydrates reacted more slowly on
insulin than normally, From that observation the authors claimed
that saturated fat causes diabetes, but they had jumped to the wrong
Saturated fat does not
produce diabetes; on the contrary. More than a dozen experiments
have shown that the best cure for people with type 2 diabetes is a
diet with much saturated fat and very little carbohydrates. In a few
days their blood sugar normalizes and many of the patients are able
to stop their medication.2 Another contradiction to
saturated fat causing diabetes is that for many years the
consumption of saturated fat has decreased in most countries and
during the same period we have seen a steady rise in type 2
The Food Administration
also published another list with eight studies which they said
contradicted their warnings. However, that list was incomplete, to
put it mildly. For instance, why didn’t they include the many
studies of the Masai people who have the lowest cholesterol ever
measured in healthy people although more than sixty percent of the
calories in their food come from saturated fat?3 And why
didn´t they mention that no study has ever found an association
between people´s cholesterol and their intake of saturated fat?
I reviewed also the
more than thirty studies having shown that patients with heart
disease or stroke have not eaten more saturated fat than healthy
individuals.4 Indeed, seven studies have found that
stroke patients had eaten less.5
The strongest proof for
causality is experiments on human beings. If saturated fat causes
heart disease, a reduction of such fat in the diet should lower the
risk, this is pure logic. But up to 1997, nine such trials had been
published and when all the results were put together in a so-called
meta-analysis, no effect was seen whatsoever. In a few of the trials
the experiment resulted in a little fewer deaths in heart disease,
but in other studies mortality had increased.4,6
How come that still
to-day saturated fat is seen as a menace to health? What is the
The truth is that there
is none. As I shall demonstrate in the following, the warnings
against saturated fat are based on manipulated data.
Ask any scientist in
this area to list the names of those who have created the diet-heart
idea and nine out of ten probably put the name Ancel Keys on the
top. Keys had no clinical experience; he was an American professor
in physiology. Maybe this explains the many curious conclusions he
has drawn from his studies about heart disease
One of his first
contributions in this area of science was a paper from 1953 where he
stated that heart disease was caused by too much fat in the diet. As
an argument he used a diagram showing the association between fat
consumption and heart mortality in six countries. It looked very
convincing, because all observations were in accord. On top was the
figures from the US; at the bottom those from Japan. In the US
people ate five times more fat than in Japan, and heart mortality
was fifteen times higher. The data from the other countries lay all
between forming a beautiful curve starting in the lower left corner
and ending in the upper right.7
But Keys’ paper was a fake. At that
time information was available from twenty-two countries. This is
what two American scientists revealed four years later.8
Their conclusion was clear: “The apparent association is greatly
reduced when tested on all countries for which data are available
instead of the six countries used by another investigator.” The
death rate from coronary heart disease in Finland, for instance, was
seven times that of Mexico, although fat consumption in the two
nations was almost the same.
But nobody reacted, and
his paper is still used by to-day’s experts as an argument for their
Also used is another of Keys´
papers, called Seven Countries.9 In that study he
followed sixteen population groups in seven different countries and
from his observations he concluded that one of the most important
factors behind heart disease was too much saturated fat in the diet.
If you eat too much saturated fat,
he claimed, your cholesterol goes up. This was what he and other
researchers had seen in dietary experiments where they had given
healthy people various amounts of fats. When they gave them much
saturated fat and little polyunsaturated fat, the fat that dominate
in most vegetable oils, their cholesterol went up. And when they did
the opposite, cholesterol went down. Their message was swallowed by
the rest of the world. Anyone who question this sacred dogma today
is considered a quack.
His idea was questioned
by Raymond Reiser, an American professor in biochemistry, who
pointed to several errors in Keys’ argumentation.10
Instead of giving the test individuals natural saturated fat from
animal food in the experiments, many authors had used vegetable oils
saturated by hydrogenation, a process that also produces trans fat,
and to-day we know that trans fat indeed causes cholesterol to go
up. In addition, when cholesterol went up, researchers attributed
the effect to high intakes of saturated fat when in fact it could
have been due to low intakes of polyunsaturated fat, and vice versa.
doesn’t raise cholesterol
What definitely argues
against a cholesterol lowering effect from saturated fat is the
outcome of modern dietary trials where scientists have used a diet
low in carbohydrates with a high content of saturated fat to combat
diabetes and/or obesity. By avoiding bread, potatoes, cakes,
cookies, candies and soft drinks these scientists have achieved
amazing results. In a few days many diabetic patients were able to
skip their insulin and the effect on body weight was much better
than those who followed the dietary guidelines.11 And
here comes the surprising finding. Even if the diet covered 20-50
percent of calories with saturated fat, nothing happened with the
patients’ cholesterol, a finding that has been confirmed in many
And there is more.
Already in the eighties American researcher Ronald Krauss found that
the most useful risk marker, the best predictor of heart disease
among the blood lipids, wasn’t the total amount of cholesterol in
the blood, neither the bad guy LDL cholesterol, but a special type
of LDL particles, the small, dense ones. The most surprising finding
was that if somebody ate much saturated fat the number of these
small, dense LDL particles decreased.13
Krauss is not only a
brilliant researcher, he is also a member of the committee who write
the dietary guidelines for the American people. When I met him in
Chicago a few years ago I asked him why they with his results in
hand still warned against saturated fat.
“Oh, you see”, he
answered, “the members of the committee do not always agree, and
when we don’t agree, we decide what to recommend by voting”.
I wonder if the
committee voted also when they discussed the study by Indian
researcher Malhotra. For six years he registered how many who died
from a heart attack among the more than one million employees of the
Indian railways. According to Malhotra’s report employees who lived
in Madras had the highest mortality. It was six to seven times
higher than in Punjab, the district with the lowest mortality, and
they died at a much younger age. But people in Punjab ate almost
seventeen times more fat than people from Madras and most of it was
animal fat. In addition they smoked much more.14
Many of the experts in
the committee must have been sceptical to Malhotra’s result: “How is
that possible? How many of you believe in such nonsense? Raise your
Maybe they hadn’t read
Malhotra’s paper? But they did know the Japanese migrant study,
because it is used again and again in the official papers as one of
their strongest arguments.
At the time of that
study Japanese ate little animal fat, their cholesterol was low, and
coronary heart disease was rare, as it is still to-day. It is of
course tempting to link them together and use it as an argument for
avoiding animal fat, in particular with the results from the migrant
study in hand.
What the investigators
found was that when Japanese people emigrated to the US, their
cholesterol went up and they died more often from heart disease, and
at that time saturated fat was a major ingredient of the food.
Isn’t this a wonderful
demonstration of the importance of avoiding saturated fat?
One of the members of
the research team was Dr. Michael Marmot, a British researcher who
has taught us much about the influence of stress and social factors
on heart disease. Marmot
found that it was not the food that raised the Japanese emigrants’
cholesterol, nor the higher cholesterol that increased their risk of
heart disease. He could state that with certainty because Japanese
emigrants who maintained their cultural traditions kept their low
risk of heart attacks, although their cholesterol increased as much
as in those who adopted a Western lifestyle. The most striking of
Marmot´s findings was that emigrants who stuck with the Japanese
traditions but preferred the fat American food ran a smaller risk
of heart disease than those who accustomed to the American way of
life but ate the lean, Japanese food.
Isn’t this a
wonderful demonstration of the unimportance of avoiding saturated
But let me return to
Seven Countries. Apparently very few have read the full 260 pages
report, because if you do that meticulously, as I have done, you
will soon discover findings that are at odds with Keys´ idea that
saturated fat causes heart disease. For instance, although the
intake was almost equal in the Finnish population groups from Turku
and North Karelia, heart mortality was five times higher in North
Karelia than in Turku. And although the intake was equal on the two
Greek islands Crete and Corfu, heart mortality was almost seven
times higher on Corfu than on Crete.
Are dairy products
Saturated fat is the
type of fat that dominates in milk, cream and cheese. Therefore,
most authorities warn against them and recommend low-fat milk, even
for the children. But where is the evidence? Is cream really
In a British report the
authors had put together data from ten large studies including more
than 400,000 men and women who had been followed for several years.
What they wanted to know was whether intake of dairy products was
deleterious to health. What they found was that the number of heart
attacks and strokes were smaller among those who consumed the most
dairy products compared with those whose intake was the lowest.16
Can we trust the WHO?
I assume that you are
curious to know how the Swedish Food Administration responded to our
criticism. They did respond, but we couldn’t find an answer to our
questions about saturated fat. Indeed, we could not even find the
term saturated fat in their text. Instead we could read statements
such as ”Our dietary guidelines are based on science….they are a
synthesis of thousands of studies…they are similar with the
Have you heard that
before?After close to twenty
years of meticulous reading of the scientific reports about this
issue I haven’t found any valid argument against saturated fat, and
I am not alone; other researchers have sought in vain as well.17
Instead, as you know already, there are a large number of
contradictory observations. Let me therefore return to the WHO/FAO
Expert Consultation1 to see what the world’s best experts
have to say about it.
According to that paper
“the relationship between dietary fats and CVD (cardiovascular
disease), especially coronary heart disease, has been extensively
investigated, with strong and consistent associations emerging from
a wide body of evidence”. This statement is followed by a reference
to a consensus report from the Nutrition Committee of the American
Heart Association.18 The only evidence presented in that
paper or in other official documents for an unhealthy effect of
saturated fat is its effect on cholesterol, and a single study
claiming that intake of saturated fat may cause heart disease.19
The first statement
that saturated fat causes cholesterol elevation is not true, as you
know by now. That intake of saturated fat causes heart disease is
not true either, although the authors said so in the summary of the
paper: “Our findings suggest that replacing saturated and trans
unsaturated fats with unhydrogenated monounsaturated and
polyunsaturated fats is more effective in preventing coronary heart
disease in women than reducing overall fat intake.”19
Probably you think that
the study was a dietary trial, but it was not. It was a study of
80,000 healthy nurses who had been followed for almost twenty
years. At the start and every other year the researchers from
Harvard asked them in detail about their usual diet. At the end of
the study the diet of those who had suffered a heart attack was
compared with the diet of those who had remained healthy. The term
“replacing” did not mean that they had replaced anything; it was a
result of complicated statistical calculations based on the dietary
information. The truth is, that on average there were just as many
statistically significant heart attacks among those who had the
lowest intake of saturated fat as among those with the highest; this
fact appears clearly from the tables in their report.
Furthermore, the research group from
Harvard has published a number of similar reports during the
previous years and none of them found a difference, and as mentioned
above, at least twenty other research groups from all over the world
haven’t succeeded either.
A relevant argument
against such studies is that what the participants tell you about
their diet is not necessarily true. Who can remember what they ate
yesterday and how much? And can we be confident that they eat
similar food and similar amounts of that food next week or next
A better way to know
how much saturated fat we have eaten is to analyze the amount of
various fatty acids present in our fat cells. It has been shown that
the number of the short saturated fatty acids reflects the intake of
saturated fat during the previous weeks or months.20 In
at least nine studies researchers have determined the amount of
these fatty acids in the fat cells. In six of them the content was
similar in patients with cardiovascular disease and in healthy
individual meaning that the patients evidently hadn’t eaten more
saturated fat than healthy people. In the rest the patients had
fewer short chain fatty acids, meaning that they had eaten less
saturated fat than the healthy control subjects.21
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