Common Cooking Oil โLinked to Weight Gain and Metabolic Issues, New Research Shows
A recent study from the University of California, Riverside (UCR) โฃhas pinpointed a potential linkโ between the widespread consumption of soybean oil and obesity, as well as โคrelated metabolic problems like fatty liver disease. โคWhile notโค inherently harmful, the sheer quantity of soybean oil in โฃthe modern Americanโ diet appears to be exceeding the capacityโ of our bodies to process โขit effectively.
The research, published in November 2023, builds upon earlier UCR findings from 2015 demonstrating that soybean oil promotesโ weight gain moreโ readily than coconut oil.โค This latest examination goes deeper, identifying specific molecules created within the body after consuming soybean oil as โฃkey drivers of these effects.
The culprit isn’t the oil itself,or even its primary fatty acid,linoleic acid,but ratherโฃ what linoleic โคacid transforms into: oxylipins. โExcessive intake of linoleic acid leads to increased oxylipin production, โขwich is associated with inflammation and fat accumulation.
Researchers โutilized genetically engineered โmice with reduced levels of enzymes responsible for converting linoleicโฃ acid and alpha-linolenic acid (another fatty acidโข in โsoybean oil)โฃ intoโค oxylipins.These โฃaltered mice exhibited healthier livers and โฃenhanced mitochondrial function, โขdemonstrating resistance to weight gain โdespite consuming aโข high-fat โคsoybean oil diet. Crucially,the study found that oxylipin levels in the liver,not โฃthe blood,correlatedโ with body weight,suggesting standard blood tests may miss early metabolic changes.
The study also revealed a โฃsurprising connection toโค cholesterol.โฃ Despite soybean oil containing no cholesterol, miceโ consuming it showed higher cholesterol levels.
The findings โare particularly relevant given theโค dramatic increase in soybean oil consumption in the United states over the pastโ century. In 1923, soybeanโ oil accounted forโค approximately 2% of total calorie intake.โ Today, that number hasโ risen to nearly 10%. This surge coincides withโฃ aโ rise in ultra-processed foods, which frequently utilize soybean oil.
“Soybean oil โisn’tโ inherently evil,” explainsโ Professor Pritpalโข Deol of UCR. “But โthe quantities in โwhich we โconsume it is triggering pathways our bodiesโค didn’t evolve to handle.”
Researchers โคareโฃ now investigating the mechanisms โคby which oxylipin formation leads to weight gain and exploring โขwhether similar effects are observed with other oils high in linoleic acid, suchโค as corn, sunflower, and safflower oil. Whileโค human trialsโ are not currently planned, theโ UCR team hopes their research will inform future nutrition policy โand public health awareness,โ drawing a parallel to the decades-long delay between identifying the link between tobacco and cancer and implementing warning labels.
Source: UC Riverside – https://news.ucr.edu/articles/2025/11/26/study-links-americas-favorite-cooking-oil-obesity