First up, let’s talk about the oil itself. When you dunk something in hot fat, you’re not just adding flavor (and calories). You’re starting a chemical party, and the guests are trans fats and advanced glycation end products (AGEs). Fun name, right? AGEs form when sugars react with proteins or fats under high heat, and they basically cause inflammation in your body. They’re like little gremlins that stiffen your arteries and mess with your cells.
And trans fats? The ones that are truly bad for you—industrial trans fats—are created when liquid oils are partially hydrogenated (a fancy way of saying “made solid by frying repeatedly”). They raise your bad cholesterol (LDL), lower your good cholesterol (HDL), and—surprise!—they increase your risk of heart disease, stroke, and type 2 diabetes. The World Health Organization wants to kick them out by 2026, but they still lurk in restaurant fryers and cheap snack foods. Lovely, huh?
