What in the world are "saturated fats"?
Chemically, saturated fat is fat that has no double bonds between carbon molecules because they are "saturated" with hydrogen molecules. Saturated fats are typically solid at room temperature and can be found in a wide variety of food sources, such as beef, lamb, pork, poultry with skin, tallow, lard, cream, butter, cheese, and dairy products made from milk.
So, what are people so worried about? Let's delve into the main concerns surrounding saturated fats...
For example, in 1996, Ascherio and colleagues conducted a study on 43,757 health professionals aged 40 to 75 that did not have either heart disease or diabetes (as of 1986). The participants were asked to complete a 131 item food frequency questionnaire and provide information about medical history, risk factors for heart disease, and dietary changes. Three follow up questionnaires were sent over the next six years for additional data. The study reported that intakes of saturated fat, total fat, and cholesterol were associated with an increased risk of myocardial infarction (heart attack) and fatal coronary heart disease.
(Find the link for this and similar studies at the end of the post below)
Of course, the main conclusion that was broadcasted in the media from this and similar studies was: saturated fat = heart problems = bad.
But, is the real story so black and white... or is there more going on?
The article also mentioned that this association between saturated fat and cardiac issues had a lot to do with fiber intakes, which has been supported by recent research.
So what does the recent research say? Let's find out...
In 2015 de Souza and colleagues conducted a meta-analysis to find potential associations of saturated fat and/or trans unsaturated fat with all cause mortality, coronary heart disease/cardiovascular disease mortality, total coronary heart disease, ischemic stroke, or type 2 diabetes from five different databases dating until May 2015. The total number from all the studies ranged between 90,501 – 339,090 participants (depending on which condition was being analyzed). The authors concluded that saturated fats are not associated with all cause mortality, cardiovascular disease, coronary heart disease, ischemic stroke, or type 2 diabetes.
(Find the links to these and similar studies at the end of the post below)
So what does all this science mean?
Please keep in mind that this is simply general information. If you are concerned about how much fat you should be consuming based on your own personal health condition, please contact your clinical nutritionist.
Ascherio, A., Rimm, E.B., Giovannucci, E.L., Spiegelman, D., Meir, S., & Willett, W.C. (1996) Dietary Fat and Risk of Coronary Heart Disease in Men: Cohort Follow Up Study in the United States. BMJ, 313, 84.
Siri-Tarino, P.W., Sun, Q., Hu, F.B., & Krauss, R.M. (2010) Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr, 91(3), 535-546.
de Souza, R.J., Mente, A., Maroleanu, A., Cozuma, A.I., Ha, V., Kishibe, T., Uleryk, E., et.al. (2015) Intake of Saturated and and Trans Unsaturated Fatty Acids and Risk of All Cause Mortality, Cardiovascular Disease, and Type 2 Diabetes: Systematic Review and Meta-analysis of Observational Studies. Brit Med J, 351, h3978.
Scarborough, P., Rayner, M., van Dis, I., & Norum, K. (2010) Meta-analysis of Effect of Saturated Fat Intake on Cardiovascular Disease: Overadjustment Obscures True Associations. Retrieved from http://ajcn.nutrition.org/content/92/2/458.long. Accessed September 11, 2015.
Shilhavy, B. (2015) Study: Government Guidelines on Low-Fat Diet Were Not Supported by Science. Retrieved from http://healthimpactnews.com/2015/ study-government-guidelines-on-low-fat-diet-were-not-supported-by-science/. Accessed September 16, 2015.