Reference Daily Intake

The Reference Daily Intake (often shortened to RDI) is a system for labeling food. It is mostly used in the United States and Canada. It gives the quantity of a nutrient that most healthy people will need in a day. The value given usually satisfied the needs for well over 90% of the healthy adults. At the start, it was developed for the United States. Other countries have started 
The RDI is used to determine the Daily Value (DV) of foods. In the United States and Canada, this information can be found on food labels (as % DV). The Food and Drug Administration (FDA) and by Health Canada require that this information is present. The labels "high", "rich in", or "excellent source of" may be used for a food if it contains 20% or more of the RDI. The labels "good source", "contains", or "provides" may be used on a food if it contains between 10% and 20% of the RDI.
The system of labeling was first introduced in 1968, and has been adapted since then.