, Volume 34, Supplement 1, pp S33–S37

Administration of docosahexaenoic acid influences behavior and plasma catecholamine levels at times of psychological stress

  • Tomohito Hamazaki
  • Shigeki Sawazaki
  • Tetsuro Nagasawa
  • Yoko Nagao
  • Yuko Kanagawa
  • Kazunaga Yazawa
Plenary Lectures

DOI: 10.1007/BF02562226

Cite this article as:
Hamazaki, T., Sawazaki, S., Nagasawa, T. et al. Lipids (1999) 34: S33. doi:10.1007/BF02562226


The purpose of the present research was to clarify the effect of docosahexaenoic acid (DHA) intake on behavior and plasma catecholamines (CA). In Study 1, 42 students took either DHA-rich oil capsules containing 1.5–1.8 g DHA/d or control oil capsules containing 97% soybean oil plus 3% of another fish oil for 3 mon in a double-blind fashion. They took a psychological test (PF Study) at the start and end of the study. This study started at the end of summer vacation and ended just before the final exams. In the control group, external aggression (aggression against others) in PF Study was significantly increased at the end of the study as compared with that measured at the start (+8.9%), whereas it was not significantly changed in the DHA group (−1.0%). In a similar double-blind study (Study 2), we measured external aggression under nonstressful conditions. External aggression slightly decreased in the control group, whereas there were no significant changes in the DHA group. In Study 3 with 14 students, plasma CA were measured at the start and end of capsule administration period of 2 mon. Subjects were under continuous stress of the final exams that lasted throughout the whole study period. The ratio of plasma epinephrine to norepinephrine concentrations was significantly increased in the DHA group (78%), whereas it stayed at the same level in the control group. In Study 4, mice were fed either DHA-deficient diet or -sufficient diet for 4 wk, and their rearing frequency (an anxiety index) was measured. In the DHA-sufficient group, the rearing frequency was significantly less than in the other group. These effects of DHA intake may be applied to people in an attempt to ameliorate stress-related diseases.





coronary heart disease


docosahexaenoic acid




eicosapentaenoic acid




polyunsaturated fatty acids


red blood cells

Copyright information

© AOCS Press 1999

Authors and Affiliations

  • Tomohito Hamazaki
    • 1
  • Shigeki Sawazaki
    • 2
  • Tetsuro Nagasawa
    • 1
  • Yoko Nagao
    • 3
  • Yuko Kanagawa
    • 1
  • Kazunaga Yazawa
    • 4
  1. 1.Department of Clinical Application, Institute of Natural Medicine, School of MedicineToyama Medical and Pharmaceutical UniversityToyamaJapan
  2. 2.the First Department of Internal Medicine, School of MedicineToyama Medical and Pharmaceutical UniversityToyamaJapan
  3. 3.Kogakkan UniversityMieJapan
  4. 4.Sagami Chemical Research CenterKanagawaJapan