Oxycholesterol or 5,6-epoxycholesterol is a form of oxidized cholesterol implicated in atherosclerosis.

[1] It is commonly formed from the reaction of fats and oxygen during high temperature cooking such as frying.

It is also shown to increase the amount of homocysteine and asymmetric dimethylarginine levels in the rabbits.

Asymmetric dimethylarginine is shown to cause adverse effects on humans in the form of cardiovascular and metabolic diseases.

Therefore it was concluded that adding oxycholesterol into diets of animals with hypercholesterolemia increases endothelial dysfunction and inflammatory response.