Dietary Fat Intake and Cardiovascular Health
What’s the Controversy?
Over the past few years, there has been an overwhelming amount of contradictory evidence and advice spewed out by the medical world regarding whether different types of dietary fats are healthy or good for us. This leads to a lot of confusion for the general public regarding what foods are considered healthy or unhealthy. However, the most recent science actually shows the opposite of what the American Heart Association has been recommending.
Different Types of Fats and What They Mean
Dietary Fats: SFA? MUFA? PUFA?
First off, let’s get a refresher on all the different types of fatty acids and what foods they are usually found in.
SFA stands for Saturated Fatty Acids. These types of dietary fats are solid at room temperature and are found mostly in animal sources, but also a few vegetable sources as well. Some examples are butter, lard, the marbling in meat, palm oil and coconut oil. They have been villainized for years, but recent research shows moderate consumption is not bad for you.
MUFA stands for Monounsaturated Fatty Acids. These are considered as healthy types of fat and tend to be liquid at room temperature. Some common examples are olives, avocados, almonds, hazelnuts, pecans, pumpkin and sesame seeds
PUFA stands for Polyunsaturated Fatty Acids. These are essential fats (required for normal bodily functions but your body can’t make it). However, PUFAs are highly unstable and oxidize at lower temperatures compared to saturated fats. They contain omega 3 and omega 6 fatty acids. They are found in both plant and animal foods. Some examples are vegetable oils such as corn, cottonseed, sunflower and soybean oils and in foods such as salmon, herring, tuna, pine nuts, walnuts, flax, pumpkin, sesame and sunflower seeds.
What the Science Says
The American Heart Association recommends aiming for a dietary pattern that achieves 5% to 6% of calories from saturated fat, especially if you have high cholesterol.
However, this recommendation does not take into account the source of the fats.
In fact, there may be more of an importance on the source of the dietary fats rather than the amount or type of fats themselves. Another factor not considered with these recommendations is the fact that virtually every source of food that contains fat, has some percentage of all 3 types, SFA, MUFA and PUFA. Even olive oil contains some saturated fat.
A current meta-analysis of cohort studies suggested that total fat, SFA, MUFA, and PUFA intake were not associated with the risk of cardiovascular disease. Furthermore, the subgroup analysis found a cardio-protective effect of PUFA in studies followed up for more than 10 years.
Another meta-analysis further demonstrated that a higher consumption of dietary SFA is associated with a lower risk of stroke, and every 10 g/day increase in SFA intake is associated with a 6% relative risk reduction in the rate of stroke. That being said, there is still research to be done in properly exploring the influence of specific SFA types and different macronutrient replacement models of SFA on stroke risk.
For cardiovascular health, substantial evidence supports the importance of the type of fat consumed, not total fat intake, and the elimination of industrially produced trans fats.
Controversies remain around the long term health effects of specific plant oils and high fat, low carbohydrate diets, thus continued research is needed to resolve these. The focus when providing dietary advice should be on the consumption of whole foods and overall dietary patterns, not on single nutrients.
If you have questions about dietary fats or low carb, high fat eating, we encourage you to contact us at anytime.