Because nutrients that would usually be found in the cereal grains are lost during the process that turns the grains into breakfast cereal. So once the grain has been turned into breakfast cereal, a coating of nutrients is sprayed back on, in order to regain it's nutritional value.
Also, fortification makes breakfast cereals appear healthier than they sometimes actually are, so it's good for marketing.
Actually the above answer is completely ridiculous. Number one, if you look at the nutrients in the grains that are in cereal and compare them to the nutrients that the cereal are fortified with, they're completely different. These aren't nutrients that are "lost during the process" in any way shape or form, that is 100% untrue.
Secondly, while it may be "good for marketing," they are not making the cereals "appear healthier than they sometimes actually are." All of the good and bad nutrition information is listed right there on the box. It's not some sly trick by the cereal companies, if it says 25% of your daily vitamin C, then that's exactly what it has in it. If it has a lot of sugar, it says that too, right on the same panel.
I would like to clarify - by "lost in the process" I was referring to the process of refining the grains into cereal, which (for most breakfast cereals) involves removing the germ and the husk from the grain. These are the parts of the cereal grain where most of the nutrients are kept. Perhaps "lost" gave the wrong impression. Also, I appreciate you opinion on "good for marketing", and that all the ingredients and nutritional analysis are on the box label. However, a cereal company is quite likely to market a cereal on it's "high calcium content" or "as a good source of folic acid" rather than the negatives - "high in sugar" etc... Hence fortification enhances marketing opportunities.
Most cereals are iron fortified. Look at the nutritional value panel on the box. It will tell you if it is iron fortified or not.
milk is fortified with vitamin D
Vitiamins
breakfast cereals.
Niacin
Six months.
Vitamin D?
vitamin D
Introducing iron-fortified cereals to a baby's diet can help prevent iron deficiency, which is important for healthy growth and development. Iron is essential for carrying oxygen in the blood and supporting brain development.
folate
Vitamin E
Vegetables and meat are good sources of fiber. All cereals have some fiber in them, some more than others. Some cereals are fortified with fiber. Read the nutrition panel on the package for specific information.