The Serotonin Zombie: Authors of New Study Try to Breathe New Life into the Dead
However, the results of the study actually support the conclusion that low serotonin is not a cause of depression.
The researchers studied three questions:
1. They asked whether people with depression had lower serotonin than healthy controls at baseline—and found that they did not.
2. They asked whether serotonin levels correlate with severity of depression—and found that they did not.
3. Finally, they asked whether people with depression dosed with an amphetamine would have less change in serotonin than people without depression dosed with an amphetamine—and here they found a statistically significant effect. But their own data shows that 10 of the 11 people with depression overlapped with healthy controls—the result was driven by one outlier.
Even The Guardian has somehow spun this into “clear evidence” that depression and serotonin are related.