Seed Oils Probably Aren’t Giving You Colorectal Cancer

Some of the worst media coverage of science I’ve ever seen

Did you know that “Canola” is an acronym that was developed because the British name for the plant — rapeseed — was considered to be hard to market for North American consumers? Now you do! Photo by Denes Kozma on Unsplash

Seed oils are a perennial favourite. We love to hate them, because they are such an easy target. We use canola, sunflower, and similar oils quite a lot in unhealthy foods because they have properties that make them easier to, for example, use in a deep fryer than things like olive oil. They’re also far cheaper than many other options, which means that they’re often used in the least healthy things you can buy in a supermarket.

And according to recent headlines, the haters were right. A range of media sources which depressingly includes the generally excellent Scientific American have been proclaiming that seed oils could be fueling colorectal cancer. According to the news, seed oils like corn, canola, and sunflower may be causing inflammation that can lead to cancer down the line.

Except, the study in question didn’t show that at all. This is quite a remarkable case in which the reporting is almost entirely divorced from the data at hand. Seed oils may not be ideal for your health — at best they are a calorie-dense food just like any other oil — but the data that they are directly causing colorectal cancer is scant.

Let’s look at the evidence.

The Study

The new piece of research that has the world going wild about seed oils was a lab-bench piece of research looking at biopsies taken from cancer patients. The authors took cells from each person’s cancer and also some extra cells from about 10cm away on their body, and compared the two groups of cells. The study was primarily looking at lipidomics, which is basically identifying the quantity and distribution of different types of fat within these cells.

This is actually a photo from the National Cancer Institute of Robert Charles Gallo, a researcher, looking at what is apparently tumor cells under a microscope. Very cool! Photo by National Cancer Institute on Unsplash

This sort of research is very complex, and also highly specific. To give you an idea of both the specificity and the complexity, here’s the results section from the abstract of the paper:

“Targeted, quantitative LC–MS/MS demonstrated a marked imbalance of pro-inflammatory mediators, with a…