Cocoa Pebbles™? Mouse droppings? No: iron ore pellets. None a part of a nutritious diet.
Weak as iron?
For decades iron has been billed as a way to build red blood cells. It is true only if a person has a deficiency in iron. Such can be caused by frequent or heavy bleeding, such as with menstruating women or regular blood donors. However for others, even a normal diet can cause a buildup of iron in the body that is toxic, called iron overload. Symptoms include heart damage, liver damage, hair loss, arthritis, and more.
The misinformation may play a part in causing 1 to 10 percent of the population to have excess iron in their bodies.
now: too much iron is dangerous
Here is what you need to know to protect your health. It is easy to reach a level of dangerous iron overload:
many types of prepared foods have extra iron added: cereal, protein bars, health drinks, and various other packaged foods.
iron is naturally present in many foods such as red meat and wheat
cooking with an iron skillet will substantially increase iron in the food prepared with it.
Add those sources up and on many days your iron intake can approach or exceed the 45mg Upper Limit.
But, a day without iron does not correct the problem. Men, postmenopausal women and children will excrete only about 1% of their body's iron stores per day. This means that iron will quickly build up in the body.
excellent additional information on iron in the diet
Begin by reading this web page on iron by the US government's National Institutes of Health. Following are some additional thoughts.
18mg is the FDA Daily Value (DV) for iron (text underneath table 2), and will be the same for the DV chart printed on packaging for cereals, etc. 18mg is more than twice the RDA for men, though. (see table 3)
One serving of many foods such as cereal is tiny for athletic men. Filling a standard bowl is two or three servings.
Many of the foods shown in tables 1 and 2 have lots of iron, and are commonly eaten. Many supplements contain Vitamin C, which increase iron absorption, as well.
summary: avoid iron unless you are a menstruating woman or blood donor
Since most people besides menstruating women and blood donors are not at all at risk for iron deficiency, and there are very harmful risks from excessive iron intake, most of those people should avoid eating foods with any iron fortification.