Because most of the time, interest in a topic is a function of plausibility. Most nootropics have little or nothing to indicate they work — not even a hint of something plausible.
Of course, it’s possible the scientific community is overlooking something promising. This has happened before. But that’s a dangerous bet for a career scientist to take.
Practically, if you want nootropics that work, and if you want to consume something whose long term side-effects are actually known, get an adderall prescription. (Or, stop trying to neurotically optimize every detail of your life and go outside.)
Because people buy it without it being proven and proving anything related to cognitive ability is both difficult and expensive.
This makes doing studies on their effectiveness a neutral to losing scenario.
Either:
The nootropic works. Great, you probably spent a decent amount of money and... The results are still going to be hard to quantify and measure. It may not be good enough results to convince people who already weren't convinced. Might as well not do it and keep making money off people who buy it without scientific studies.
Or
The nootropic doesn't work. Shit. Bury the results and never publish or risk losing a money maker.
Indeed, it seems to me that a paper proving that nootropics are either harmful or helpful would be quite publishable, which is (unfortunately?) what modern science is all about.
I have two hypotheses that came to mind when I read your question:
1. It’s a hard problem to quantify effects on cognitive functioning provided by nootropic supplements. We still have so much to learn about brain function;
2. Nootropics offer patent holders opportunities to make obscene amounts of money. As long as those supplements are (generally) safe to consume. That level of review requires R&D spending, but too much investigation may inadvertently reveal that these money-making “miracle” products are far less effective than the manufacturers claim.
I don't think 1. is correct. There is a large body of research looking into different dimensions of brain function, and how different conditions impair those functions.
For example, look at the N-back test for working memory. This is popular in the nootropics community, and is widely used in clinical pharmacology research. There are plenty of other tests. Scientists do experiments like "measure how impaired you are on alcohol vs. antihistamines" to compare impairment profiles from different modes of drug action.
You can measure impairment from sleep deprivation, alcohol, etc., so of course you can measure improvement in attention, reaction speed, working memory, spatial reasoning, and so on.
The difficulty with quantifying effects is not that we need to learn about brain function to know how to measure them, it's that nootropics have quite small effect sizes, if any.
I think it's entirely about 2 -- large studies are expensive, and unless your effect size is enormous you need a large study to detect it.
1. is certainly true. to my mind, an accurate quantitative measure of brain function doesn't exist: you run into the fairly intractable philosophical problem of "what is brain function?"
while that is true, not being 100% philosophically sound has never stopped psychology studies before - far from it
2. is also perfectly true, with the caveat that it only applies to beneficiaries of the patents.
so your hypotheses account for beneficiaries of the patents, and scientists who aren't willing to broach the subject of measuring brain function, but what about the complement of those subsets? what about non-beneficiaries who are willing to quantify brain function? are they simply a small enough subset that it justifies the observation? or is there another hypothesis to be found? or perhaps the observation is flawed in itself
Way too many variables to control for which makes any scientific findings incredibly difficult to validate. Tough to make a career on it and way to many conflict of interests.
It's too bad because if someone could legitimately find conclusive results that would be really helpful.
It feels like its a part of the medical space that the mainstream part of the medical community has shunned which has allowed for a lot of less scrupulous individuals to take up the mantel (See all the podcasts etc). It's too bad because there is probably something to it but its tough to validate/quantify.
If I run a quick search on PubMed, there are a handful focused on cognitive enhancement and other effects on healthy brains, e.g. https://pubmed.ncbi.nlm.nih.gov/35366192/
1) It's hard to sell the output of this research. Your health insurance isn't going to pay $100 a day to make a healthy person smarter.
2) The output of your research is going to be low priority for regulatory approval
3) As both result and cause of the above, there's virtually no existing funding for this kind of research
4) If you succeed, you're going to spark an immediate furor over fairness and the morality of human enhancement (which I'm not saying I personally agree with, but it will happen)
The person you're replying wrote no one wants to study the effects of nootropics in healthy adults.
Sick people with insurance, particularly chronically ill ones, or those with illnesses that threaten their lives, are where I'd imagine the majority of money is made. You could probably argue treating the ill is more psychologically impactful work too. That's going to skew where researcher's focus their attention, especially if their work is funded by private industry.
I imagine there aren't many scientists who want to enable their own line of work descending into a doping arms race like some sports can in the absence of anti-doping regulations.
Edit: or if they do catch on to something, a moral panic breaking out and having to do drugs tests on the regular or something
