Reductive Assumptions About Fatty Acids

Fir ForestAre we reaching a point where the reductive assumptions embedded in dietary recommendations are more confusing than helpful? A new paper in Scientific Reports begs this question. Yutang Wang and colleagues find evidence that polyunsaturated fatty acids are associated with a small reduction in cardiovascular mortality in the general population of the U.S., but not for persons with existing cardiovascular disease.

These results are consistent with systematic reviews of the evidence for primary prevention of cardiovascular disease. A Cochrane review tells us “reducing saturated fat intake for at least two years causes a potentially important reduction in combined cardiovascular events.”

The Problem with Broad Generalizations and Reductive Assumptions

Certainly, on some levels, the advice to cut back on saturated fatty acids across the board makes perfect sense. But if you look a little closer, the picture is not totally consistent. For instance, the authors note:

“Whether the food sources of fatty acids affect the associations between fatty acids and heart disease mortality in our study is unclear. Of note, French fries represented a major source of polyunsaturated fatty acids. French fries are generally perceived as less healthy; however, two recent studies (here and here) showed that French fries were not associated with cardiovascular disease mortality.”

So is it the individual foods that matter? Or should we dive into the reductionist rabbit hole and obsess about individual components of our food?

Fries and Milk and Energy Bars

Shall we think of French fries as a healthy snack because they’re a good source of polyunsaturated fats? Not really. Is whole milk and cheese bad for us because of all that saturated fat? Probably not. Is an ultra-processed energy bar a healthier choice because it has all the right nutritional entities? Maybe not.

In our view, the strongest argument favors stepping back from all of this and concerning ourselves with overall dietary patterns. A reductive approach to nutrition and food can do more harm than good – especially if it serves mainly to help us rationalize unhealthy patterns for eating. That’s because it helps food marketers prop up their health claims. And their health claims are mainly about selling us ever more units of food.

Click here for the study by Wang et al and here for more on nutrition claims in food marketing.

Fir Forest, painting by Gustav Klimt / WikiArt

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January 30, 2023

One Response to “Reductive Assumptions About Fatty Acids”

  1. January 30, 2023 at 8:31 am, David Brown said:

    Reductive assumptions about saturated and polyunsaturated fatty acids perpetuates this dispute.

    Concerning ourselves with overall dietary patterns does not hold much promise of resolving the dispute. Why? Because dietary pattern research lacks precision. To explain how the fatty acid profile of the food supply affects health status requires experiment and measurement.

    A plant-based food pattern is widely endorsed these days because it results in favorable health outcomes. However, that approach generates its own set of problems.