Some people are concerned that when they discontinue the use of nootropics, they will experience cognitive functioning below that of their normal level; however, this is usually not the case, especially regarding nootropics in the racetam class. Discontinuing nootropics will cause a person to lose any benefits experienced on these drugs. In other words, nootropics do not appear to build up the brain in any long-lasting way; their benefits are directly tied to their use. There is no evidence that nootropics erode one’s natural level of cognitive functioning.
The power calculation indicates a 20% chance of getting useful information. My quasi-experiment has <70% chance of being right, and I preserve a general skepticism about any experiment, even one as well done as the medical student one seems to be, and give that one a <80% chance of being right; so let’s call it 70% the effect exists, or 30% it doesn’t exist (which is the case in which I save money by dropping fish oil for 10 years).
We’d want 53 pairs, but Fitzgerald 2012’s experimental design called for 32 weeks of supplementation for a single pair of before-after tests - so that’d be 1664 weeks or ~54 months or ~4.5 years! We can try to adjust it downwards with shorter blocks allowing more frequent testing; but problematically, iodine is stored in the thyroid and can apparently linger elsewhere - many of the cited studies used intramuscular injections of iodized oil (as opposed to iodized salt or kelp supplements) because this ensured an adequate supply for months or years with no further compliance by the subjects. If the effects are that long-lasting, it may be worthless to try shorter blocks than ~32 weeks.
In 2011, a story surfaced that struck fear into many: A woman was being treated for brain and memory disorders, when in reality she was just incredibly low in B12 stores. Turns out, this isn’t uncommon; many physicians don’t run routine blood tests for the nutrient, which is especially troublesome considering that our ability to absorb B12 is dramatically reduced with age. Over time, low vitamin B12 can do a number of your cognition.
Ngo has experimented with piracetam himself (“The first time I tried it, I thought, ‘Wow, this is pretty strong for a supplement.’ I had a little bit of reflux, heartburn, but in general it was a cognitive enhancer. . . . I found it helpful”) and the neurotransmitter DMEA (“You have an idea, it helps you finish the thought. It’s for when people have difficulty finishing that last connection in the brain”).
In fact, when combined into a variety of different supplement “stacks” and taken in the correct dosage, these compounds – usually referred to as either smart drugs or nootropics (but now also including the category of psychedelics) – can completely change how your brain performs, including impacting receptor sites for neurotransmitters, altering levels of enzymes that break down specific neurotransmitters, changing cell membrane structures and thus controlling the movement of molecules inside and outside of the cell, increasing cerebral perfusion, which improves blood flow to the brain, affecting what are called “biogenic processes”, including neuronal cell creation or “neurogenesis”, and neuroendocrine regulation, regulating hormonal processes of the body specifically related to cognition (See additional studies here, here, here and here.).

the larger size of the community enables economies of scale and increases the peak sophistication possible. In a small nootropics community, there is likely to be no one knowledgeable about statistics/experimentation/biochemistry/neuroscience/whatever-you-need-for-a-particular-discussion, and the available funds increase: consider /r/Nootropics’s testing program, which is doable only because it’s a large lucrative community to sell to so the sellers are willing to donate funds for independent lab tests/Certificates of Analysis (COAs) to be done. If there were 1000 readers rather than 23,295, how could this ever happen short of one of those 1000 readers being very altruistic?

Methylphenidate – a benzylpiperidine that had cognitive effects (e.g., working memory, episodic memory, and inhibitory control, aspects of attention, and planning latency) in healthy people.[21][22][23] It also may improve task saliency and performance on tedious tasks.[25] At above optimal doses, methylphenidate had off–target effects that decreased learning.[26]