Where the ‘kink’ is in the fat molecule decides whether it harms blood vessels — a kink at position 9 or 9+12 is bad, but at position 11 is harmless.

Two types of artificial trans fats found in fried and baked foods make blood vessel cells more inflamed and less able to produce a chemical that helps blood vessels relax, but a different trans fat found in dairy doesn’t do this.

A type of trans fat found naturally in dairy and meat doesn’t harm blood vessel cells in the lab, even though it looks similar to the harmful ones in fried foods.

These two harmful trans fats cause blood vessel cells to produce excess harmful oxygen molecules, which then trigger inflammation and block the production of a key chemical that keeps blood vessels healthy.

These two trans fats interfere with how insulin tells blood vessels to relax by blocking key signals in the cell, but other fats don’t have this effect.