Unsaturated fats

Structure of unsaturated fats
Unsaturated fats are on of the two main types of fat. They contain a minimum of one double bond between two carbons atoms in a fatty acid chain. This makes them take up more space, so the fat as a whole is less solid than a saturated fat. This means that they may stay in liquid form when stored in room temperature. If they have many double bonds, they are referred to as polyunsaturated fats.

Cis and trans fats
Cis and trans describe the bonds between carbon atoms in the fatty acid chains. Though both have double bonds, there are many differences in their appearance and structure. In a cis fat, the carbon chain continues on the same side as previously. Because of the double bond, this creates a change of direction in the fatty acid string, which will make a cell membrane more fluid. Trans fat, by contrast, will continue on the opposite side, and making the carbon atoms diagonal. This will preserve the original direction of the chain, leaving it straight, and contributing to more rigid cell membranes.

Consumption of unsaturated fats
Most humans should aim to consume more unsaturated fats than saturated ones, and in particular cis fats. This is not because saturated fats are more unhealthy in themselves, but because it is common to have a large baseline consumption of them that should be balanced out. Good sources of unsaturated fats are avocado, vegetable oil, fish, peanut butter, nuts and seeds.