Is saturated fat the enemy? Update on current research
Like many aspects of nutrition, the message around fat is ultra confusing.
For many years we were told to cut down fat. Now we are told that sugar is actually the enemy and we shouldn't worry about fatty food. Yet, doctors are still recommending to reduce your saturated fat intake to prevent cardiovascular diseases (CVD).
So, should we stop eating saturated fat?
In a world where we all crave for simple answers, I am afraid to report that there isn't one. Or, if there is, we don't know it, yet!
Nevertheless, research is making progress and there are some useful and evidence-based recommendations that I can share with you.
For the bottom-line on saturated fat scroll down to the last paragraph, otherwise read my summary on Minihane's paper on "The big fat debate", Nutrition Bulletin March 2018
For many years the recommendation was to reduce saturated fat (or SFA, standing for saturated fatty acids). This was mainly based on findings from a large observational study, where high intake of SFAs were associated with higher CVD risk (Keys et al. 1986)
But a more recent research paper (a meta-analysis and systematic review by Chowdhury et al. 2014) consolidated all the existing evidence from the past decades and challenged the initial findings: the association between SFA and CVD risk was not consistent across all studies and they concluded that the link between the two wasn't evidence-based.
So, came this question: Should the recommendations of reducing SFAs intake be revised?
The truth is, as often in nutrition, that the picture is slightly more complexe than we initially thought.
The recommendations on SFAs and CVD risk were based on an incomplete understanding of the topic: we ignored presence of confounding factors (lifestyle, diet as a whole), we assumed that all SFAs had the same effect on CVD, and we didn’t consider the importance of what would people be replacing SFAs with (Givens et al. 2017).
A more in-depth analysis of all the mechanisms at play is required and the current recommendations need to be refined (and the SACN - Scientific Advisory Committee on Nutrition - is working on this) but that doesn't mean that we should ditch completely the current principle that SFA should be consumed with caution.
Based on what we know to date, here are some useful advice about Saturated Fatty Acids (SFAs):
Reducing all SFAs in our diet might not be the ultimate answer to reducing CVD risk because not all SFA are equals.
For instance, dairy products (with the exclusion of butter) appear to have a protective effect against CVD risk (possibly due to the calcium content and the food matrix).
Meanwhile food high in SFA such as lauric, myristic and palmitic acids - found in meat, coconut and palm oils - are considered to raise levels of bad cholesterol (LDL-cholesterol)
What we replace the SFAs with is possibly as important as reducing their intake.
If replaced with simple carbs (refined sugar, white bread, white rice, pasta) the risk on CVD might be higher!
instead, prefer replacing them by complex carbs such as brown rice, barley, wholegrain or pulses; and by unsaturated fats such as fish, olive, nuts and seed oils.
make sure that you eat two portions of fish (including one of oily fish) weekly. More research are required but current evidence highlight a possible benefit of omega 3 on CVD risk (in addition to cognitive function benefit. It would be silly to avoid them)