MINERALS Dietitians may recommend that dietary minerals are best supplied by ingesting specific foods rich with the element(s) of interest. Sometimes dietary minerals are ingested as part of dietary supplements , the most common being iodine in iodized salt .
FIBRES Dietary fiber (fibre) , sometimes called roughage , is the indigestible portion of plant foods that pushes food through the digestive system , absorbs water and eases defecation . It acts by changing the nature of the contents of the gastrointestinal tract , and by changing how other nutrients and chemicals are absorbed. [ 1]