A new meta-analysis contends that limiting dietary saturated fat does nothing for reducing heart disease events or for heart disease prevention. The conclusion is based upon a review of over 100 studies, representing over 75,000 participants. By sheer numbers alone, that starts to feel pretty compelling.
The study's conclusions run against the advice of most health authorities, including the American Heart Association, which advocates limiting saturated fat intake to under 6% of calories. In case you’re wondering, that works out to under 13 grams for an average 2000 kcal per day diet.
And against common knowledge. After all, doesn't everyone know that saturated fat increases LDL (bad) cholesterol?
Even though dietary saturated fatty acid intake tends to increase LDL levels, the researchers argue that in most individuals the precise type of LDL that is increased is not the type most closely linked to heart disease risk. LDL comes in many forms including small dense particles – the ones most associated with cardiovascular risk – and big fluffy particles, which appear to be less toxic. Saturated fat tends to increase the big fluffy portion, leaving the small dense proportion unaffected. Ergo, all good to eat more butter – and steak, and put gobs of cream in your coffee.
This all sounds good – well, actually GREAT - until you read the study carefully and discover a couple of important caveats:
- First, the authors primarily bolster their argument by comparing the health outcomes of people who continue to eat a high sat fat diet to those who switch to a low fat but highly processed high carb diet. DUH. We already know that diets based on highly processed foods are bad for health regardless of fat content.
- Second, the trials that consistently link LDL and heart disease have studied total LDL not LDL composition markers. So yes, there may be variability in small dense and big fluffy fractions, but total LDL seems to matter a lot as well.
- Finally, most of the authors receive financial support from various Dairy Councils, as well as the National Cattleman’s Beef Association. Caveat emptor.
But I won’t throw out the baby with the bathwater here. To their credit, the researchers also came to another consensus that is incredibly important and that we SHOULD always keep in mind: “the health effects of foods cannot be predicted by their content in any nutrient group, without considering the overall macronutrient distribution.”
Food is a complex bioactive substance acting on an incredibly complex biologic system. It’s almost impossible to take one nutrient and determine its effects without considering the context or delivery vehicle of that nutrient. The saturated fat in dark chocolate, for example, comes in a delivery vehicle that has multiple beneficial health effects including anti-oxidative, antihypertensive, anti-inflammatory, anti-atherogenic, and anti-thrombotic properties, as well as preventive effects against cardiovascular disease and type 2 diabetes. Meanwhile, the saturated fat in a bratwurst comes in a package that has been shown to increase overall death rates, including those from cancer.
This has been seen in other nutritional contexts as well: it may be why supplements don’t work.
At Step One Foods we’ve always remained focused not only on lowering LDL cholesterol but the ingredients we use to attain that outcome. We understand that nutrition is much more complex than one nutrient or even one health effect.
In the end, the study is another good argument as to why it’s so hard to judge the healthiness of food by a nutrition panel. And, of course, yet another reason to follow the simplest dietary advice ever: Eat real food. Not too much. Mostly plants. That dietary advice actually allows for the inclusion of some saturated fat – just not too much and more likely from the right sources.
And now I'm going to go and have my Dark Chocolate Crunch bar!