Dear Cheesy
Low blood iron levels and iron-deficiency anaemia are either caused by excessive bleeding (in women who menstruate this is usually due to excessive blood loss during menstruation, but it can also be due to internal bleeding such as from an ulcer), or a lack of available iron in the diet. Vegetarians tend to develop iron-deficiency anaemia if they exclude all animal products, esp red meat and liver which are the best sources of bioavailable iron in our diets. Other foods that are rich in bioavailable iron include fish, egg yolk, poultry, iron-fortified cereals and bread, and dried fruit. Although many plant foods like spinach have a very high iron content, the iron is not available for absorption because it is bound up by chemicals called phytates that occur in spinach.
Best regards
DietDoc