[epaladin]

Vitamin C is in so many things now that it seems unlikely that the additional vitamin c in strawberries would have much of an effect. There's a lot of positive benefit of long-term consistent consumption of various fruits (such as the study that showed an association between blueberries and brain health) but for such an effect on mood in the short term it could be that you just like them :). But hey, if it works, it works!

[mrfusion]

Well at the time I was dieting pretty hard, so it might be possible to have had a short term deficiency of vitamin C. But good.

If I recall I did a correlation analysis, between foods and mood and strawberries related jumped out strongly.

[derefr]

Strawberries contain serotonin! This is pretty well-studied; it's hypothesized they do it because serotonin in the gut acts as a laxative, causing you to expel the strawberry seeds without digesting them.

If the serotonin manages to make it into your bloodstream (e.g. if your gut bacteria don't want it, and your stomach pH isn't low enough to destroy it, and your gut permeability is high) then you'll certainly get a mood boost.