Among 24 male blood donors without anaemia who had been giving a mean of 2.2 donations per year involving a mean blood loss of about 900 ml a year, 10 (41%) were found to be depleted of storage iron. This is somewhat higher but similar to the previously recorded findings in healthy women without anaemia. The results may well support a policy of limiting blood donation to twice a year in men and to once a year in women. Both men and women blood donors require medicinal iron after each donation. It is considered that storage iron depletion in non-anaemic women is not in the main related to pathological levels of menstrual loss but rather to inadequate dietary iron. Food iron in present-day diets should be supplemented.