As part of an ongoing project on the behavioral consequences of tryptophan depletion, I read an article today that claimed to have found a positive correlation between high levels of corn consumption and homicide across many nations. The researchers claimed that corn, being deficient in tryptophan, chronically depletes serotonin levels, thereby increasing incidents of physical violence.
I was fascinated by the claim, albeit rather incredulous. But, rather than pursue the question of tryptophan’s effects on suicide, I decided to look into a question I’ve often wondered about: the correlation of GDP and suicide rates.
After some data diving of my own, using GDP data from the IMF and suicide data from WHO, I found no meaningful correlation between suicide rates and GDP. Interestingly, a simple scatterplot of the relevant data sets reveals that, for each gender separately, there are several very substantial outliers that make any such correlation impossible to find, as you can see below.
So the question I’m left with is, “what variables explain the very different suicide rates seen across nations in this data set?”