Can High-Temperature Cooking Create Trans Fat?

Yes—but the amount depends strongly on temperature and time, and routine cooking should not be described as if it turns vegetable oil into partially hydrogenated shortening.

A systematic review and meta-analysis of 33 studies covering 21 oils found that heating below 200°C had minimal impact on trans-fat levels. Between about 200 and 240°C, trans-fat levels increased with temperature, and prolonged heating increased them further.

Everyday Lipid takeaway Normal cooking temperatures at or below roughly 200°C appear to generate little additional trans fat. Very high temperatures and prolonged heating can increase trans isomers, another reason to avoid severe overheating.

Can High-Temperature Cooking Create Trans Fat?

Everyday Lipid takeaway Normal cooking temperatures at or below roughly 200°C appear to generate little additional trans fat. Very high temperatures and prolonged heating can increase trans isomers, another reason to avoid severe overheating.

References - Influence of Heating during Cooking on Trans Fatty Acid Content of Edible Oils: A Systematic Review and Meta-Analysis. PMID: 35406103.