If your iron is low, eating a diet that is high in iron-rich foods such as fortified cereals, red meat, dried fruit, and beans may not be enough to give you what you need. Your doctor might recommend that you take an iron supplement.
selective. 1  having the function or power of selecting; making a selection. 2  characterized by selection, especially fastidious selection. 3  of or relating to selection. 4  Electricity, Radio. having good selectivity.
If you break down the two words, selective means to only pick certain things, and permeable means to let pass through. When you talk about something being selectively perme â¦ able, it usually refers to a cell membrane because it only lets in certain nutrients and lets out proteins and what not. In human terms, a DOOR is permeable, but a wall is not. [and technically speaking, sometimes a window is permeable]    So, if a membrane is selectively permeable this means that only some things can go in or out through the membrane.