What are overages in fortified food products?

Some cereals may contain more added vitamins and minerals than the label reflects. These “overages” occur when manufacturers deliberately add extra nutrient, either to ensure that it will be at the advertised level throughout the product’s shelf life or to compensate for expected breakdown of unstable vitamins. Overages vary depending on the stability of the added ingredient. Unstable nutrients, such as vitamin A, generally require high overages. Larger amounts are also sometimes added accidentally, which can cause illness.