- Solid at room temperature
- Available carbon bonds are occupied by a hydrogen atom
- All the carbon-atom linkages are filled-or saturated-with
- Found in animal fats
- Found in some plant sources
- cocoa butter, coconut, palm and palm kernel oils
- Proper utilization of essential fatty acids.
- Consumption of Saturated fats may allow for better retention
of Omega-3 fatty acids
in serum and liver (Garg 1989, 1990)
- Protect liver from alcohol and possibly other toxins (Cha
& Sachan 1994, Nanji 1995)
- Saturated fatty acids are resistant to heat-induced degradation,
unlike Polyunsaturated fats
(Grootveld 2001, Halvorsen 2011)
The role of saturated fat in cardiovascular disease has become
- Prevailing hypothesis influencing US public policy
- High Saturated Fat --> High Cholesterol --> Heart Disease
- Saturated fats can be converted to cholesterol
- Main cause of high blood cholesterol, according to American
- For each 5 percent increase of energy intake from saturated
fat, a 17 percent increase in the risk of coronary disease (relative
risk, 1.17%; 95 percent confidence interval) as compared with
equivalent energy intake from carbohydrates (Hu 1997)
- Total fat intake was not significantly related to the risk
of coronary disease
- Meta-analysis of randomized controlled trials finds that
increasing consumption of polyunsaturated
fat as a replacement for saturated fat reduces the risk of
coronary heart disease (Mozaffarian 2010).
- Plasma concentrations of even chain saturated phospholipid
fatty acid are positively related to subsequent coronary heart
disease risk, whereas, concentrations of omega-6 phospholipid
fatty acid are inversely related (Khaw 2012).
- Interestingly, blood monounsaturated fatty acids, omega-3
poly-unsaturated fatty acids, and trans-fatty
acids were not consistently associated with coronary heart
- Authors admit factors other than diet (eg: genetic differences
in metabolism) may alter blood fatty acid levels.
- Other studies listed under Alternative Hypothesis (below)
are frequently presented in support of the Lipid Hypothesis,
but in fact refute the Lipid hypothesis upon closer scrutiny.
- Alternative hypothesis suggests cardiovascular disease is
not a result of high saturated fat intakes as once widely believed
- but instead a biological response resulting in chronic
- likely triggered by sedentary lifestyle and other dietary
issues including, but not limited to high Linoleic
to Linolenic fatty
acid ratio and over consumption of sugars.
- misunderstandings of saturated fats have been attributed
to studies design flaws, unethical manipulation of data, and
misrepresentation or misinterpreted of findings. (Texon 1989)
- Others have suggested publication biases favoring studies
that continue to reinforce particular political and industrial
agendas to influence public policy. (Also see USDA
The Seven Countries Study
- First landmark study that linked the consumption of dietary
fat to coronary heart disease
- This study served as the basis for nearly all of the initial
scientific support for the Cholesterol Theory.
- It was later discovered that the author unethically selectively
analyzed information from only
seven countries to prove his correlation
- rather than comparing all available data from all 22 countries,
which it turns out, showed no correlation between dietary fat
and heart disease after all.
- Began 1948 and involved 6,000 subjects from Framingham, Massachusetts,
- Identified heart disease risk factors such as smoking, high
blood pressure, lack of exercise and high cholesterol.
- The cholesterol link was weak.
- Subject who weighed more and had abnormally high blood cholesterol
levels were slightly more at risk for future heart disease
- However, subject who ate more saturated fat, more dietary
cholesterol and more calories actually were the most physically
active, weighed the least and had lower serum cholesterol levels.
- Noted by Dr. William Castelli, a former director of the Framingham
Heart study (Catelli 1992).
The Cholesterol-heart Disease Hypothesis Critique (Texon
- Meyer Texon, MD calls into question the lipid hypothesis
- Claims that the American Heart Association and the National
Institute of Health misrepresent scientific data.
- Pointed out abuses of statistical analysis in studies such
as the Helsinki Heart Study and the National Heart, Lung, and
Blood Institute's multimillion dollar studies.
- "Thus, after seven years at a cost of $150 million dollars
studying 3,806 men, the difference in death was 3 men."
- Questioned the proposed benefit to cost relationship for
attempting to lower cholesterol.
- Calls for more promising alternative directions for atherosclerosis
U.S. Multiple Risk Factor Intervention
- Sponsored by the National Heart, Lung, and Blood Institute
- Compared mortality rates and eating habits of over 12,000
- Men with "good" dietary habits (reduced saturated
fat and cholesterol, reduced smoking, etc.)
- Demonstrated marginal reduction in total coronary heart disease.
- Demonstrated higher overall mortality from all causes.
- increase in deaths from cancer, brain hemorrhage, suicide,
and violent death.
- After 10 years, no significant difference in death from heart
disease or total death.
The South Carolina Experience (Lackland 1990)
- A survey of South Carolina adults found no correlation of
blood cholesterol levels with consumption of nine fat intake
habits, including the consumption of red meat, fat on meat, fried
fish/chicken, butter, eggs, whole milk, bacon/sausage, cheese,
and the use of solid fats when cooking vegetables.
Post-mortem Autopsies (Felton 1994)
- Comparisons of aortic plaques with serum and adipose tissue
imply a direct influence of dietary polyunsaturated fatty acids
on aortic plaque formation.
- No associations were found with saturated fats
- Arterial plaque is primarily composed of unsaturated fats,
particularly polyunsaturated fats.
Review of Literature (Ravnskov 1998)
- Reviewed studies examining direct link between dietary fats
and atherosclerotic vascular disease in humans.
- The review included ecological, dynamic population, cross-sectional,
cohort, case-control studies, and controlled, randomized trials
of the effect of fat reduction alone.
- He concludes that there is little evidence that Saturated
Fatty Acids as a group are harmful or that Polyunsaturated Fatty
Acids as a group are beneficial.
Meta-analysis (Siri-Tarino 2010)
"A meta-analysis of the prospective epidemiologic
studies showed that there is no significant evidence for concluding
that dietary saturated fat is associated with an increase of
risk of CHD or CVD."
Review of Literature (Hoenselaar 2011)
- Results and conclusions about saturated fat intake in relation
to cardiovascular disease from leading advisory committees, do
not reflect the available scientific literature.
Review of Dietary Fat Guidelines (Harcombe 2016)
- Dietary fat guidelines have prevailed for almost 40 years.
- The evidence base at the time of their introduction has been
examined for the first time and found lacking.
- Evidence currently available provides no additional support.
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polyunsaturated fatty acids and composition of human aortic plaques.
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BA, Hennekens CH, Willett WC (1997). Dietary fat intake and the
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