THE SKINNY ON FATS: How Dietary Fats Influence Cardiovascular Disease Risk

Poor diets are a key risk factor for cardiovascular disease (CVD), the leading cause of death among adults in developed countries.  While there is no doubt that poor diets contribute to CVD, precisely what constitutes a poor diet in terms of cardiovascular risk is still a matter of debate.  


The dietary fats at the center of the debate are saturated fatty acids, monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids PUFAs).  PUFA’s are further broken down into two groups; omega-6 and omega-3 fatty acids. Each of these types of fats, depending upon how much is consumed in relation to other types, has a different effect on blood lipids as well as on other risk factors for CVD.


Based upon he media and popular culture’s fixation with the saturated fat controversy, one could easily assume that reducing saturated fat is no longer important for heart health.  This recent movement fueled by both media and some health professionals can be compelling at first glance. Without taking the entire body of research linking saturated fat intake with increased CVD into account, incorrect conclusions are promoted.


While it is true that some saturated fat can certainly be a part of a healthy diet and that cholesterol is needed by the body for a number of critical biological functions, the fact remains that the vast majority of scientific evidence supports reducing saturated fat.  


The issue should not be whether saturated fat contributes to CVD, but what to replace it with.  Overall, the body of research indicates that when saturated fats are replaced with refined carbohydrates, such as added sugars, CVD risk is unchanged, and some risk factors such as triglycerides actually increase.  However, the consumption of fiber-rich carbohydrates is associated with a decreased risk of heart disease without any detrimental effects on triglycerides.


Replacing saturated fats in the diet with MUFA such as those found in olive oil, is also associated with improvements in many cardiovascular disease-related risk factors, such as cholesterol and blood pressure.


Dietary fat-what types and how much-is an important consideration for cardiovascular health.  While controversies persist, it is currently possible to come to some evidence-based conclusions.  Lowering the amount of saturated fat in the diet is beneficial for cardiovascular health. However, what replaces the saturated fat is crucial.  Selecting MUFAs and PUFA’s (particularly omega-3s) reduce the risk of CVD. Likewise, replacing the saturated fat with whole, unrefined carbohydrates, including whole grains, is beneficial.