When researchers engineered mice with a tweaked liver protein and fed them the same soybean oil-rich diet as normal mice, the engineered mice stayed lean whilst their untampered with compatriots expanded rapidly. Interestingly, the culprit wasn't necessarily the oil itself but what happens when your liver breaks it down into compounds called oxylipins. More oxylipins = more fat.
The tricky bit is that oxylipins only show up in liver tissue, not blood, so standard health checks won't catch them until the damage is done, and the enzymes that create them vary by genetics, which explains why some people gain weight whilst others don’t.
The extraordinary thing is that soybean oil now makes up 10% of US calories, up from 2% a century ago and some estimates suggest 60% of processed foods now contain it. The researchers are also testing whether other vegetable oils trigger the same response, suggesting this might be less about soybeans and more about modern diets. Regardless, it looks like we have our first major scapegoat.
An artists’ impression of the trial results
🧐 What's in it for me? If you're metabolically unlucky, soybean oil could be sneakily sabotaging you in ways that don't show up in routine tests. And in case you weren’t already full of bad news, other high-linoleic oils like corn and sunflower oils may trigger the same response. If, on the other hand, you are Robert F. Kennedy Jr., well done, hears some vindication.
💵 Out of the Lab: The processed food industry won't welcome this research, but alternative oil producers certainly will.
If these effects gain broader recognition, expect a quiet shift towards oils with lower linoleic acid content. Zero Acre Farms, which produces cultured oils optimised for health could benefit from increased scrutiny of conventional seed oils.
Until next time, stay curious.
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