Fat food for a bad mood. Could we treat and prevent depression in Type 2 diabetes by means of omega-3 polyunsaturated fatty acids? A review of the evidence.
OBJECTIVE
Evidence strongly suggests that depression is a common complication of Type 2 diabetes mellitus. However, there is considerable room to improve the effectiveness of pharmacological antidepressant agents, as in only 50-60% of the depressed subjects with diabetes does pharmacotherapy lead to remission of depression. The aim of the present paper was to review whether polyunsaturated fatty acids (PUFA) of the omega-3 family could be used for the prevention and treatment of depression in Type 2 diabetes.


METHODS
MEDLINE database and published reference lists were used to identify studies that examined the associations between omega-3 PUFA and depression. To examine potential side-effects, such as on glycaemic control, studies regarding the use of omega-3 supplements in Type 2 diabetes were also reviewed.


RESULTS
Epidemiological and clinical studies suggest that a high intake of omega-3 PUFA protects against the development of depression. There is also some evidence that a low intake of omega-3 is associated with an increased risk of Type 2 diabetes, but the results are less conclusive. Results from randomized controlled trials in non-diabetic subjects with major depression show that eicosapentaenoic acid is an effective adjunct treatment of depression in diabetes, while docosahexanoic acid is not. Moreover, consumption of omega-3 PUFA reduces the risk of cardiovascular disease and may therefore indirectly decrease depression in Type 2 diabetes, via the reduction of cardiovascular complications.


CONCLUSIONS
Supplementation with omega-3 PUFA, in particular eicosapentaenoic acid, may be a safe and helpful tool to reduce the incidence of depression and to treat depression in Type 2 diabetes. Further studies are now justified to test these hypotheses in patients with Type 2 diabetes.
Pouwer
F
F
Vrije Universiteit Medical Centre, Department of Medical Psychology, EMGO Institute, Amsterdam, the Netherlands. f.pouwer@vumc.nl
Nijpels
G
G
Beekman
A T
AT
Dekker
J M
JM
van Dam
R M
RM
Heine
R J
RJ
Snoek
F J
FJ
D000328:Adult; D003866:Depressive Disorder / Q000517:prevention & control*; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy / Q000523:psychology*; D015525:Fatty Acids, Omega-3 / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic
D015525:Fatty Acids, Omega-3