[Depressive symptoms and serum levels of polyunsaturated fatty acids omega-3 and omega-6 among college students from Northern Mexico].

INTRODUCTION

Previous studies suggest that low consumption as well as low serum levels of polyunsaturated fatty acids (PUFA) omega-3 and a high omega-6/omega-3 ratio may be implicated in the etiology of depressive disorders, however, epidemiologic evidence is inconclusive.

OBJECTIVE

To assess the relationship of serum levels of omega-3 fatty acids (docosahexaenoic [DHA], eicosapentaenoic [EPA], alpha-linolenic fatty acid [ALA]) and the omega-6 (arachidonic acid [AA])/EPA ratio with depressive symptoms among Mexican college students.

MATERIAL AND METHODS

A cross-sectional study that included 60 male and female participants (ages 18 to 24 years) with serum levels of EPA, DHA, ALA and AA. Depressive symptoms were ascertained with the Center for Epidemiologic Studies Depression (CES-D) scale validated for Mexican students. Linear regression was used to assess the relationship between depressive symptoms and serum PUFA omega-3 and omega-6.

RESULTS

Serum levels of EPA, DHA and EPA/DHA ratio were not related to depressive symptoms, high serum ALA was related with lower depressive symptoms before and after covariate adjustment; however, these results were not statistically significant. Among women, 1% increase in EPA resulted in 5.5. (p = 0.57) increase in the depressive scale scores while 1% increase in ALA resulted in 6.7 decrease (p = 0.39) in the scores.

CONCLUSIONS

Our results did not confirm the relationship of serum levels of PUFA omega-3 and omega-6/omega-3 ratio with depressive symptoms; the negative correlation of serum ALA with depressive symptoms remains to be confirmed in prospective studies.