Polyunsaturated omega-6 fatty acids are found in vegetable oils. The fatty acids are then processed into long-chain fatty acids. This means metabolism has a major influence on the level of circulating fatty acids. Researchers have already identified the link between the level of certain fatty acids (linolic acid or dihomo gamma-linolenic acid) and a lower or higher risk of diabetes; however, it remains unclear whether certain lipid classes in blood plasma, i.e., categories of lipid-like molecules, play a role.

To help determine this, Marcela Prada, Fabian Eichelmann and Matthias Schulze and further researchers from the DIfE and DZD cooperated with the European Prospective Investigation into Cancer and Nutrition (EPIC) Potsdam cohort. The investigation included 1,602 probands, 536 of whom have type 2 diabetes. At the start of the study, all participants provided detailed information regarding previous or preexisting conditions, lifestyle, height, and weight. Using state-of-the-art measuring technology, the researchers characterized hundreds of lipid molecules in the blood samples and the activity of the delta-5 desaturase enzyme, which plays an essential role in the processing of unsaturated fatty acids.

At the beginning of the study, all participants provided information on previous illnesses, their lifestyle as well as their height and weight. Using state-of-the-art measurement methods, the scientists characterized hundreds of lipid molecules from the blood samples and the activity of the enzyme delta-5-desaturase. It plays an important part in the processing of unsaturated fatty acids.

Fig.: Testing of various lipid classes shows that, in certain lipid classes, a higher level of linolic acid is associated with a lower risk of type 2 diabetes, meanwhile, in most lipid classes, a higher level of dihomo gamma-linolenic acid is linked to a higher risk. © Marcela Prada, Erand Llanaj / DIfE

Fatty Acids Provide Clues to Higher or Lower Risk of Developing Type 2 Diabetes
The fatty acid arachidonic acid was not found to be associated with the risk of diabetes in any of the tested examined lipid classes, although, in certain lipid classes, the researchers did find evidence that linolic acid is linked to a lower risk of type 2 diabetes. In contrast, a higher concentration of dihomo gamma-linolenic acid was found to correlate to a higher risk. Furthermore, the researchers also reported that, in certain lipid classes, those with greater delta-5 desaturase activity had a lower risk of developing diabetes.

“Our study offers new insights into the role of polyunsaturated fatty acids as a biomarker for type 2 diabetes,” says study lead author Marcela Prada who conducts her research at both DIfE and DZD. “If it proves possible to modify the concentration of certain types of fatty acids, this would result in a new approach for preventing type 2 diabetes”.

Original publication:
Marcela Prada, Fabian Eichelmann, Clemens Wittenbecher, Olga Kuxhaus, Matthias B. Schulze. Plasma Lipidomic n-6 Polyunsaturated Fatty Acids and Type 2 Diabetes Risk in the EPIC-Potsdam Prospective Cohort Study. Diabetes Care 2023, https://doi.org/10.2337/dc22-1435