I've really enjoyed this talk by Molly Crockett: Beware neuro-bunk. The speaker outlines the limitations of modern neuroscience when accessing the effectiveness of dietary supplements intended to enhance cognition. I believe the speaker mentioned that 68% of (americans?) take dietary supplements for a variety of reasons.
I've done some research, and these compounds typically go into "neuro enhancing" products:
- DMAE
- GABA
- N-Acetyl-L-Tyrosine
- Vinpoceitine
- 5-HTP
- Vitamin B complex
This got me thinking: How does one assess the effectiveness of dietary supplements on cognition? These are low- dose compounds that may be taken at random times of a day, combined with assorted other supplements. How does one study the effects of something like that? Is there a "gold standard" study that I can take a look at to understand how this is done?
What I'm interested in is how do they account for the time of day, and other supplements/drugs/activity that happened and followed the study.
When thinking about "real psychoactive drugs", their effect is much more profound, and thus easier to study, with a fairly well defined onset times, intensity curves. For example, I can go to erowid.org and see curves like the one below for
With a graph like that, one can with a reasonable certainty estimate the duration and intensity of effects. But what about dietary supplements? Is it just big placebo?