Iron plays an important role in the lives of almost all organisms.
Fish also has a lot of iron.
Spinach also contains certain amounts of iron. The composition of the plant, however, has substances that prevent full absorption. Therefore, nutritionists recommend the Spinach is served with meat or fish. Thus, the so-called trace elements (which are about 60 in number, including iron, copper, zinc, selenium, nickel, etc.) are absorbed properly by the body.
Interestingly, the legend that spinach contains a lot of iron, was born after a typo. When describing results of a 1870 German study of iron content in different foods, the decimal point in the value of spinach was shifted to the right by mistake, the result was published ten times higher value. The error was corrected only in 1937, but the press and films, like "Popeye the Sailor" had already validated the myth of iron-rich spinach in the mass consciousness, say scientists from the Medical University in Indiana, USA.
The need for iron per 1 kg weight for kids is- 0.6 mg, for adults - 0.1 mg. for pregnant women - 0.3 mg per day.
As a rule, iron, dietary intake is sufficient, but in some special cases like (anemia, blood donation) the adoption of iron supplements is necessary.
You must know that an overdose of iron damages the body and can be fatal.