I have seen a number of articles recently about flax seeds preventing hair loss. Apparently, the key are flax lignans, which are found in flax seeds, but not in flax oil.

You can buy ground flax seeds at most grocery stores, or if you want to save some money, you can purchase whole flax seeds and grind them up in a food processor. They are particularly good on top of salad and cereal. Be sure to refrigerate them after grinding.

http://www.dentalplans.com/Dental-Health-Articles/Natural-Supplement-Shows-Promise-for-Hair-Loss.asp