Cis fatty acid

A cis fatty acid is an unsaturated fatty acid that has similar or identical groups (usually –H groups) on the same side of a double bond. cis fatty acids are isomers of trans fatty acids, in which the –H are arranged one on each side of the double bond.

Fatty acids with cis double bonds are not straight chains but have a "knee" at the point where the double bond is; On the contrary, trans are rectilinear; cis double bonds are much more common in living beings than trans ones.

Molecular structure diagram of different fatty acids
Saturated fatty acid	Fatty acid cis- unsaturated	Fatty acid trans- unsaturated
Saturated carbon atoms (each with 2 hydrogens) joined by a single link	Unsaturated carbon atoms (each with 1 hydrogen) joined by double link. Settings cis	Unsaturated carbon atoms (each with 1 hydrogen) joined by double link. Settings trans