This Common Fat Could Be Fueling Type 2 Diabetes, Researchers Warn

Scientists are uncovering why some dietary fats may worsen metabolic disease while others appear to help protect against it.

A new study is shedding light on how two common dietary fats may influence the risk of developing type 2 diabetes, a disease linked to serious health complications worldwide.

The research, published in Trends in Endocrinology & Metabolism, was led by scientists from the CIBER Area for Diabetes and Associated Metabolic Diseases (CIBERDEM) at the University of Barcelona.

According to Professor Manuel Vázquez-Carrera, palmitic acid and oleic acid appear to affect the body in very different ways.

“Palmitic acid, a saturated fatty acid widely found in foods, is associated with impaired insulin sensitivity, whereas oleic acid, abundant in olive oil, may have a protective effect against these metabolic disorders,” says Vázquez-Carrera.

Other contributors to the study include Ricardo Rodríguez-Calvo of the Pere Virgili Institute for Health Research (IISPV), Marta Tajes of the Bellvitge Biomedical Research Institute (IDIBELL), and Walter Wahli of the University of Lausanne (Switzerland).

The Importance of Fat Quality

The researchers say the findings reinforce the idea that the type of fat people consume may matter more than the total amount.

“This review highlights the significant role of the quality of dietary fat, rather than the total amount consumed,” notes Professor Manuel Vázquez-Carrera, who is a group leader at CIBERDEM at the UB.

As Xavier Palomer (UB-IBUB-CIBER-IRSJD), the article’s first author, says, “at the molecular level, palmitic acid promotes the accumulation of potentially toxic bioactive lipids, fosters low-grade chronic inflammation, and contributes to the dysfunction of cellular organelles, such as the endoplasmic reticulum and the mitochondria.” The researchers add that these processes “are closely linked to impaired insulin action and the progression of metabolic disease.”

Contrasting Effects on Metabolism

Oleic acid appears to have a much more beneficial metabolic profile. Found in high amounts in olive oil, it helps store fats in forms that have less impact on normal body functions. It also supports healthy insulin signaling in important tissues including the liver, muscles, and adipose tissue.

The researchers say oleic acid may also reduce many of the damaging effects linked to palmitic acid. This could help explain why diets rich in monounsaturated fats, including the Mediterranean diet, are often associated with a lower risk of type 2 diabetes and other metabolic conditions.

The study also calls for more targeted research to better understand conflicting results seen in some epidemiological studies. “It is important to consider variables such as the source of fatty acids, their dietary context, interactions with other nutrients, and different food processing methods,” says Vázquez-Carrera.

The team believes a clearer understanding of these factors could improve how scientists evaluate the effects of dietary fats on metabolic health and help guide more effective nutrition strategies for preventing and managing type 2 diabetes.

Reference: “Palmitic and oleic acids in type 2 diabetes mellitus” by Xavier Palomer, Ricardo Rodríguez-Calvo, Marta Tajes, Walter Wahli and Manuel Vázquez-Carrera, 29 March 2026, Trends in Endocrinology & Metabolism.
DOI: 10.1016/j.tem.2026.01.003

Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.