This would be a very time-consuming experiment. Any attempt to combine this with other experiments by ANOVA would probably push the end-date out by months, and one would start to be seriously concerned that changes caused by aging or environmental factors would contaminate the results. A 5-year experiment with 7-month intervals will probably eat up 5+ hours to prepare <12,000 pills (active & placebo); each switch and test of mental functioning will probably eat up another hour for 32 hours. (And what test maintains validity with no practice effects over 5 years? Dual n-back would be unusable because of improvements to WM over that period.) Add in an hour for analysis & writeup, that suggests >38 hours of work, and 38 \times 7.25 = 275.5. 12,000 pills is roughly $12.80 per thousand or $154; 120 potassium iodide pills is ~$9, so \frac{365.25}{120} \times 9 \times 5 = 137.

Although piracetam has a history of “relatively few side effects,” it has fallen far short of its initial promise for treating any of the illnesses associated with cognitive decline, according to Lon Schneider, a professor of psychiatry and behavioral sciences at the Keck School of Medicine at the University of Southern California. “We don’t use it at all and never have.”

Nootropics can also show signs of neuro-preservation and neuro-protection. These compounds directly affect the levels of brain chemicals associated with slowing down the aging process. Some nootropics could in an increase in the production of Nerve Growth Factor and Brain-Derived Neurotrophic Factor to stimulate the growth of neurons and neurites while slowing down the rate of damage as well.
Today, extraordinary research is showing that bacopa has the remarkable ability to increase levels of BDNF, a protein responsible for the growth, maintenance and survival of neurons, and the creation of new neural connections in the brain. It also has been shown to help promote the growth of new neurons and neural pathways, which helps to explain why it’s such a powerful memory and concentration booster.
Lost confidence.  If you can’t find your keys, much less get through your workday in a timely fashion without a slew of mistakes, you are going to lose confidence in both your brain and yourself.  When you cannot remember where you put things and it takes an absurd amount of effort just to do a simple task, you might question your very sanity.  As your confidence continues to nose-dive, you just end up making more and more mistakes.  It turns into a vicious cycle.
This is not something you notice when you talk to Seltzer. And though our memory is probably at its peak in our early 20s, few 30-year-olds are aware of a deficit. But Seltzer considers himself a transhumanist, in the mould of the Oxford philosopher Nick Bostrom and the futuristic writer and inventor Ray Kurzweil. Transhumanists are interested in robots, cryogenics and living a really, really long time; they consider biological limitations that the rest of us might accept, or even appreciate, as creaky obstacles to be aggressively surmounted. On the ImmInst (Immortality Institute) forums, Seltzer and other members discuss life-extension strategies and the potential benefits of cognitive enhancers. Some members, Seltzer among them, use a drug called piracetam, which was first marketed by a Belgian pharmaceutical company in 1972 and in recent years has become available in the US from retailers that sell supplements. Although not approved for any use by the FDA, piracetam has been used experimentally on stroke patients - to little effect - and on patients with a rare neurological condition called progressive myoclonus epilepsy, for whom it proved helpful in alleviating muscle spasms. Data on piracetam's benefits for healthy people is virtually nonexistent, but many users believe that the drug increases blood flow to the brain.
"Over the years, I have learned so much from the work of Dr. Mosconi, whose accomplished credentials spanning both neuroscience and nutrition are wholly unique. This book represents the first time her studies on the interaction between food and long-term cognitive function reach a general audience. Dr. Mosconi always makes the point that we would eat differently and treat our brains better if only we could see what we are doing to them. From the lab to the kitchen, this is extremely valuable and urgent advice, complete with recommendations that any one of us can take."
Amphetamine – systematic reviews and meta-analyses report that low-dose amphetamine improved cognitive functions (e.g., inhibitory control, episodic memory, working memory, and aspects of attention) in healthy people, and in individuals with ADHD.[21][22][23][25] A 2014 systematic review noted that low doses of amphetamine also improved memory consolidation, in turn leading to improved recall of information in non-ADHD youth.[23] It also improved task saliency (motivation to perform a task) and performance on tedious tasks that required a high degree of effort.[22][24][25]