Finally, more evidence that points to what we already knew...
Dietary intakes of saturated fats are not linked to cardiovascular disease, so says a meta-analysis from across the world.
The conclusion that dietary intake of saturated fat was not associated with an increase in coronary heart disease or cardiovascular disease was reported in the American Journal of Clinical Nutrition this past February, 2010.
This study accumulated data from almost 350,000 subjects in twenty-one different studies. The data from these study subjects showed the development of approximately 11,000 cases of Coronary Heart Disease (CHD) or stroke. However, there was no link established between the subject's saturated fat intake and the incidence of CHD, stroke, or Cardiovascular Disease (CVD), and this did not change when the researchers focused their research to consider age or sex, or the quality of the study.
"Our meta-analysis showed that there is insufficient evidence from prospective epidemiologic studies to conclude that dietary saturated fat is associated with an increased risk of CHD, stroke, or CVD," wrote the researchers, led by Dr Ronald Krauss from the Children's Hospital Oakland Research Institute in California.
"[However,] nutritional epidemiologic studies provide only one category of evidence for evaluating the relation of saturated fat intake to risk for CHD, stroke, and CVD. An overall assessment requires consideration of results of clinical trials as well as information regarding the effects of saturated fat on underlying disease mechanisms, as discussed elsewhere in this issue. Nonetheless, a summary evaluation of the epidemiologic evidence to date provides important information as to the basis for relating dietary saturated fat to CVD risk," the researchers said.
The study, funded by the US National Dairy Council, Unilever, and the National Institutes of Health, challenges the mainstream majority thinking that saturated fats are detrimental to heart health.
The old "lipid hypothesis" tried to show a direct relationship between the amount of saturated fat and cholesterol in the diet and the incidence of coronary heart disease. This lipid hypothesis for heart disease received a huge amount of publicity and public favor, in spite of the fact that other studies showed this hypothesis to not be true many years ago.
In the last 50 years, big food processing companies jumped on the bandwagon and pushed the lipid hypothesis even further into the mainstream. Oddly enough though, prior to the 1920's, coronary heart disease was very rare in America. Americans ate lots of lard, butter, beef and cheese, but heart attacks and strokes were uncommon.
While vegetable oils and hydrogenated fats were pushed as the "healthy choice" over saturated fats for the next forty years, the incidence of coronary heart disease actually increased dramatically, so much so that today, heart disease remains a primary cause of death in the U.S. With the advent of the revised food pyramid, grains and carbohydrates pushed those numbers up even higher.
If heart disease had any connection to saturated fats in the diet, how could it be that the use of saturated fats has gone down, while the use of processed vegetable oils like margarine, shortening, and trans fats-as well as sugar and grain-based processed foods have increased dramatically?
Clearly something has been amiss here.
Oils like canola, corn, soybean, and sunflower have been pushed as the healthy substitutes over saturated fats. It is these oils, though, that contribute to inflammation in the body, and upset the ratio of Omega 3 fatty acids and Omega 6 fatty acids.
Diets high in vegetable oils -especially hydrogenated vegetable oils, cause a variety of health problems, including inflammation. This inflammation leads to an increased tendency to form blood clots, which leads to heart attacks and strokes, now at higher than ever levels in the U.S.
Most of the fat in our bodies and in the food we eat comes in the form of triglycerides, which are made of three fatty-acid chains attached to a glycerol molecule. Elevated triglycerides in the blood are usually linked to a higher than average potential for heart disease, but triglycerides do not come directly from dietary fats. Triglycerides are made in the liver from sugars that have not been burned for energy. Excess sugars in the body are from starchy carbohydrates, particularly refined sugar and white flour. It appears that triglycerides and vegetable oils and excessive Omega 6 fatty acids are causing much of the problem.
So you see, saturated fats are not the villains they have been portrayed to be, nor are they the cause of today's diseases; in fact quite the opposite is true.
Saturated fats play an important role in the body in several ways:
• Saturated fatty acids make up at least 50% of the cell membranes. They give cell walls their necessary stiffness and integrity.
• Saturated fats are extremely important for bone health. For calcium to be effectively utilized in our bones at least 50% of dietary fats should be saturated--so skim milk will not help your bones.
• Saturated fats are vital to the liver and help protect it from toxins such as alcohol and other drugs.
• Saturated fats strengthen the immune system.
• They are needed for the proper utilization of other essential fatty acids - Omega 3 fatty acids are better retained in the tissues and utilized by the body when the diet is rich in saturated fats as well.
• The fat around the heart muscle is actually highly saturated. The heart draws on this reserve of fat in times of physical stress.
• Saturated fats lower a substance in the blood called Lp(a), or Lipoprotein(a), that indicates a tendency towards heart disease.
• Short- and medium-chain saturated fatty acids have important antimicrobial properties. They protect us against harmful microorganisms in the digestive tract.
The scientific evidence is beginning to pile up and does not (and never did) support the assertion that saturated fats clog arteries and cause heart disease.
So while saturated fats have not yet been exonerated in the mainstream public, the tide is beginning to turn. You as an educated consumer, and your own health advocate know the truth about saturated fats vs. the evils of vegetable oils and refined foods. Enjoy your grass fed steaks, butter, cheese and lard and know you are doing your body good.
References:
Mary G. Enig, PhD, and Sally Fallon, "The Skinny on Fats", Weston A. Price Foundation, Jan, 1999.
Stephen Daniells, "Saturated Fats Not Linked to Heart Disease: Meta Analysis", Food Navigator.com, February 2010.
P.W. Siri-Tarino, Q. Sun, F.B. Hu, R.M. Krauss, "Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease", American Journal of Clinical Nutrition, February 2010.
To visit US Wellness Meats, click here.
For another great article on the importance of eating saturated fat by the Weston A. Price Foundation, click here.
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