Food intolerances, or the inability to metabolise certain substances pferrous gluconate and elemental itab ferrous fumarate and folic acidronresent in food, are part of the large group of disorders called “adverse food reactions”. Unlike allergies, they are not triggered by the immune system and are definitely more widespread. They usually occur through dermatitis (atopic), asthma and difficulty breathing, vomiting, diarrhoea or abdominal cramps.