All living things store usable chemical energy in the bonds of chemical compounds. Most organisms store energy as [ fats]] and oils. These biomolecules are very large; large means more bonds and therefore more stored . The main component of animal fats and vegetable oils are triglycerides. Each triglyceride molecule is made of one molecule as the backbone and three fatty acids. The formula for a triglyceride can vary because (1) the length of each fatty acid chain can vary from 14 to 24 carbons; (2) it may contain as many as three different fatty acids; and (3) the bonds between atoms may be either single and/or double covalent bonds. See the figure above. In a fatty acid only single bonds are found between carbon atoms. “Saturated” indicates that the carbon atoms hold all the possible hydrogen atoms that can be attached. Saturated fats contain only saturated fatty acid chains. An unsaturated fatty acid contains one or more double bonds in the carbon atom chains. “Unsaturated” indicates that more hydrogen atoms can be attached to the carbon atoms.

The main difference between fats and oils is that fats are solids at room temperature while oils are liquids. Oils, usually from plant materials, contain mostly unsaturated fatty acids. Fats, on the other hand, usually come from animals and contain many saturated fatty acids.

Nutrition science refers to mono-unsaturated fats as “ ”. Olive oil and canola oil are both mono-unsaturated. Mono-unsaturated fats are thought to increase the levels of good cholesterol (HDL) by taking the LDL to the liver to be broken down and removed from the body. It is believed that saturated fatty acids increase the levels of (LDL) and contribute to clogged arteries.