Defining exactly what a healthy diet is when it comes to preventing hair loss can be a little more complex. Principally, the main vitamins, minerals, and nutrients that one must ingest in some form to maintain healthy hair are vitamin A, all B vitamins-particularly vitamins B-6 and B-12, folic acid, biotin, vitamin C, vitamin E, copper, iron, zinc, iodine, protein of course, silica, essential fatty acids (EFA’s, formerly known as vitamin F) and last but not least one must consume water.