Professor David O Kennedy published a book in 2014 called Plants and the Human Brain. In his book he summarizes the last 15 years of research into cognitive nutrition, including the work he's done with colleagues at the Brain Performance Nutrition Research Center at Northumbria University. It's a great read and a good guide to what sorts of herbs and other plants to include in our weekly diet and it is all based on hard science rather than mere assertion or trendy but unsubstantiated beliefs.
Harriet Hall, MD also known as The SkepDoc, is a retired family physician who writes about pseudoscience and questionable medical practices. She received her BA and MD from the University of Washington, did her internship in the Air Force (the second female ever to do so),  and was the first female graduate of the Air Force family practice residency at Eglin Air Force Base. During a long career as an Air Force physician, she held various positions from flight surgeon to DBMS (Director of Base Medical Services) and did everything from delivering babies to taking the controls of a B-52. She retired with the rank of Colonel.  In 2008 she published her memoirs, Women Aren't Supposed to Fly.
Pop this pill and improve your memory. Swallow that one and reduce your cognitive decline. We see ads for such products all the time and I suspect they will increase as the baby boomers reach senior citizenhood. The most popular brain boosting supplements are fish oil pills and they are also probably the best studied ones. The results are not encouraging. When all the studies are pooled, we are left with the possibility of a barely significant improvement in recalling lists of words soon after they have been learned, but the effect does not last. Extracts of the ginkgo biloba tree are also popular, and here the prospects are even dimmer. There is no impact on memory, despite claims of increased circulation in the brain. And ginkgo can interfere with the action of anticoagulants and has also been shown to be an animal carcinogen.
Like everything else in your body, the brain cannot work without energy. The ability to concentrate and focus comes from an adequate, steady supply of energy - in the form of glucose in our blood to the brain. Achieve this by choosing wholegrains with a low-GI, which release glucose slowly into the bloodstream, keeping you mentally alert throughout the day. Opt for 'brown' wholegrain cereals, granary bread, rice and pasta.
Unlike many hypothetical scenarios that bioethicists worry about - human clones, "designer babies" - cognitive enhancement is already in full swing. But how much do they actually help? Are they potentially harmful or addictive? Then there's the question of what we mean by "smarter". Could enhancing one kind of thinking exact a toll on others? All these questions need proper scientific answers, but for now much of the discussion is taking place furtively, among the increasing number of people who are performing daily experiments on their own brains.
Sometimes called smart drugs, brain boosters, or memory-enhancing drugs, the term "nootropics" was coined by scientist Dr. Corneliu E. Giurgea, who developed the compound piracetam as a brain enhancer, according to The Atlantic. The word is derived from the Greek noo, meaning mind, and trope, which means "change" in French. In essence, all nootropics aim to change your mind by enhancing functions like memory or attention.
By the way, since I’ll throw around the term a few more times in this article, I should probably clarify what an adaptogen actually is. The actual name adaptogen gives some hint as to what these fascinating compounds do: they help you to adapt, specifically by stimulating a physiological adaptive response to some mild, hormesis-like stressor. A process known as general adaptation syndrome (GAS) was first described by the 20th-century physician and organic chemist Hans Selye, who defined GAS as the body’s response to the demands placed upon it. When these demands are excessive and consistent, it can result in the common deleterious symptoms now associated with long-term exposure to chronic stress. GAS is comprised of an alarm stage (characterized by a burst of energy), a resistance stage (characterized by resistance or adaptation to the stressor), and – in the case of excessive and chronic stress – an exhaustion stage (characterized by energy depletion). Adaptogens are plant-derived compounds capable of modulating these phases of GAS by either downregulating stress reactions in the alarm phase or inhibiting the onset of the exhaustion phase, thus providing some degree of protection against damage from stress.

…researchers have added a new layer to the smart pill conversation. Adderall, they’ve found, makes you think you’re doing better than you actually are….Those subjects who had been given Adderall were significantly more likely to report that the pill had caused them to do a better job….But the results of the new University of Pennsylvania study, funded by the U.S. Navy and not yet published but presented at the annual Society for Neuroscience conference last month, are consistent with much of the existing research. As a group, no overall statistically-significant improvement or impairment was seen as a result of taking Adderall. The research team tested 47 subjects, all in their 20s, all without a diagnosis of ADHD, on a variety of cognitive functions, from working memory-how much information they could keep in mind and manipulate-to raw intelligence, to memories for specific events and faces….The last question they asked their subjects was: How and how much did the pill influence your performance on today’s tests? Those subjects who had been given Adderall were significantly more likely to report that the pill had caused them to do a better job on the tasks they’d been given, even though their performance did not show an improvement over that of those who had taken the placebo. According to Irena Ilieva…it’s the first time since the 1960s that a study on the effects of amphetamine, a close cousin of Adderall, has asked how subjects perceive the effect of the drug on their performance.

A key ingredient of Noehr’s chemical “stack” is a stronger racetam called Phenylpiracetam. He adds a handful of other compounds considered to be mild cognitive enhancers. One supplement, L-theanine, a natural constituent in green tea, is claimed to neutralise the jittery side-effects of caffeine. Another supplement, choline, is said to be important for experiencing the full effects of racetams. Each nootropic is distinct and there can be a lot of variation in effect from person to person, says Lawler. Users semi-annonymously compare stacks and get advice from forums on sites such as Reddit. Noehr, who buys his powder in bulk and makes his own capsules, has been tweaking chemicals and quantities for about five years accumulating more than two dozens of jars of substances along the way. He says he meticulously researches anything he tries, buys only from trusted suppliers and even blind-tests the effects (he gets his fiancée to hand him either a real or inactive capsule).

If you want to try a nootropic in supplement form, check the label to weed out products you may be allergic to and vet the company as best you can by scouring its website and research basis, and talking to other customers, Kerl recommends. "Find one that isn't just giving you some temporary mental boost or some quick fix – that’s not what a nootropic is intended to do," Cyr says.
For this batch, I tried out NOW Foods Magnesium Citrate Powder ($7 for 227g); the powder was still a bit sticky but much easier to work with than the Solgar pills, and the 227g made 249 gel capsule pills. The package estimates 119 serving of 315mg elemental magnesium, so a ratio of 0.315g magnesium for 1.9g magnesium citrate, implying that each gel cap pill then contains 0.152g magnesium (\frac{(119\times315)}{249}=150) and since I want a total dose of 0.8g, I need 5 of the gel cap pills a day or 35 per block.

Dr Hart explained how communication between the gut and the brain is controlled via our immune system, our endocrine system (hormones) and our central nervous system, which are all under the influence of the bacteria in our gut. The types and amount of these bacteria, known as our gut microbiome, can be directly impacted by factors such as diet, stress, pollution and medications (2) and the composition of the microbiome is also understood to affect one’s susceptibility to food sensitivities and intolerances (3).  

Starting from the studies in my meta-analysis, we can try to estimate an upper bound on how big any effect would be, if it actually existed. One of the most promising null results, Southon et al 1994, turns out to be not very informative: if we punch in the number of kids, we find that they needed a large effect size (d=0.81) before they could see anything:
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The powder itself is quite bulky; the recommended dose to hit 200mg of absorbed magnesium leads to ~7g of powder (so capping will be difficult) and the container provides only 30 doses’ worth (or each dose costs $1!). It’s described as lemon-flavored, and it is, but it’s sickly-sweet unpleasant and since it’s so much powder, takes half a glass of water to dissolve it entirely and wash it down. Subjectively, I notice nothing after taking it for a week. I may try a simple A-B-A analysis of sleep or Mnemosyne, but I’m not optimistic. And given the large expense of LEF’s Magtein, it’s probably a non-starter even if there seems to be an effect. For sleep effects, I will have to look at more reasonably priced magnesium sources.
I have elsewhere remarked on the apparent lack of benefit to taking multivitamins and the possible harm; so one might well wonder about a specific vitamin like vitamin D. However, a multivitamin is not vitamin D, so it’s no surprise that they might do different things. If a multivitamin had no vitamin D in it, or if it had vitamin D in different doses, or if it had substances which interacted with vitamin D (such as calcium), or if it had substances which had negative effects which outweigh the positive (such as vitamin A?), we could well expect differing results. In this case, all of those are true to varying extents. Some multivitamins I’ve had contained no vitamin D. The last multivitamin I was taking both contains vitamins used in the negative trials and also some calcium; the listed vitamin D dosage was a trivial ~400IU, while I take >10x as much now (5000IU).
“It is surprising and encouraging that it may be possible to predict the magnitude of a placebo effect before treatment,” says Tor Wager, a neuroscientist at the University of Colorado Boulder, who was not involved in the research. More work is needed to see how the predictive features hold up in other populations and for different pain conditions, he says.
Also known as Arcalion or Bisbuthiamine and Enerion, Sulbutiamine is a compound of the Sulphur group and is an analogue to vitamin B1, which  is known to pass the blood-brain barrier very easily. Sulbutiamine is found to circulate faster than Thiamine from blood to brain. It is recommended for patients suffering from mental fatigue caused due to emotional and psychological stress. The best part about this compound is that it does not have most of the common side effects linked with a few nootropics.
A constituent of the turmeric spice, curcumin was first discovered for its brain health benefits when epidemiological studies revealed those in regions with a high consumption of the curry spice turmeric had fewer reported cases of cognitive diseases. It is theorized that the unmatched anti-inflammatory power of curcumin, in combination with its unique antioxidant make-up, inhibits the formation of amyloid build up in the brain.
Research does not support that drugs like Ritalin help students do well in school. Studies show that prescription stimulants do not help to improve learning or thinking in those who do not actually have ADHD. Further, research reveals that students who abuse prescription stimulants have lower GPAs than students who do not abuse the drugs.[14] Although Ritalin improves concentration, this effect is largely misunderstood among non-prescribed users. These illicit users mistakenly believe that they can use a drug out of its prescribed context, thinking they can reap the benefits intended for legitimate users.
Piracetam (known also by the name Nootropil) is one of the best known Nootropics and makes up part of the Racetam family along with Aniracetam, Phenylpiracetam, Pramiracetam, Oxiracetam, Nefiracetam, Coluracetam and Nebracetam. These are all synthetic compounds that have been created in the lab, but there are also a number of effective herbal and natural nootropic supplements.
[…] The 7 Best Brain Boosting Supplements | Live in the Now … – … much research has indicated that certain supplements can help sustain and promote excellent brain function as we age. The supplements recommended by the Alzheimer’s Prevention and … Take adequate supplements for brain and help your kids to perform well in their tests by enhancing … […]
Low-dose lithium orotate is extremely cheap, ~$10 a year. There is some research literature on it improving mood and impulse control in regular people, but some of it is epidemiological (which implies considerable unreliability); my current belief is that there is probably some effect size, but at just 5mg, it may be too tiny to matter. I have ~40% belief that there will be a large effect size, but I’m doing a long experiment and I should be able to detect a large effect size with >75% chance. So, the formula is NPV of the difference between taking and not taking, times quality of information, times expectation: \frac{10 - 0}{\ln 1.05} \times 0.75 \times 0.40 = 61.4, which justifies a time investment of less than 9 hours. As it happens, it took less than an hour to make the pills & placebos, and taking them is a matter of seconds per week, so the analysis will be the time-consuming part. This one may actually turn a profit.
I noticed what may have been an effect on my dual n-back scores; the difference is not large (▃▆▃▃▂▂▂▂▄▅▂▄▂▃▅▃▄ vs ▃▄▂▂▃▅▂▂▄▁▄▃▅▂▃▂▄▂▁▇▃▂▂▄▄▃▃▂▃▂▂▂▃▄▄▃▆▄▄▂▃▄▃▁▂▂▂▃▂▄▂▁▁▂▄▁▃▂▄) and appears mostly in the averages - Toomim’s quick two-sample t-test gave p=0.23, although a another analysis gives p=0.138112. One issue with this before-after quasi-experiment is that one would expect my scores to slowly rise over time and hence a fish oil after would yield a score increase - the 3.2 point difference could be attributable to that, placebo effect, or random variation etc. But an accidentally noticed effect (d=0.28) is a promising start. An experiment may be worth doing given that fish oil does cost a fair bit each year: randomized blocks permitting an fish-oil-then-placebo comparison would take care of the first issue, and then blinding (olive oil capsules versus fish oil capsules?) would take care of the placebo worry.
I take my piracetam in the form of capped pills consisting (in descending order) of piracetam, choline bitartrate, anhydrous caffeine, and l-tyrosine. On 8 December 2012, I happened to run out of them and couldn’t fetch more from my stock until 27 December. This forms a sort of (non-randomized, non-blind) short natural experiment: did my daily 1-5 mood/productivity ratings fall during 8-27 December compared to November 2012 & January 2013? The graphed data29 suggests to me a decline:
According to McCabe's research team, white male undergraduates at highly competitive schools are the most frequent student users of neuroenhancers. Users are also more likely to belong to a fraternity or a sorority, and to have a grade point average (GPA) of 3.0 - ie satisfactory - or lower. They are 10 times as likely to report that they have smoked marijuana in the past year and 20 times as likely to say that they have used cocaine. In other words, they are decent students at schools where to be a great student you have to give up a lot more partying than they're willing to give up.
I’m sure your office already has a coffee maker, but if you’re in the mood for a refreshing coffee twist at the office, try this cold brew option from Chameleon Cold Brew. They use a highly select blend of 100% organic, fair trade certified Arabica coffee beans and filtered Texas Hill Country water. The result is a super smooth, less acidic and highly caffeinated coffee, which can be enjoyed hot or cold.
One of the most common strategies to beat this is cycling. Users who cycle their nootropics take them for a predetermined period, (usually around five days) before taking a two-day break from using them. Once the two days are up, they resume the cycle. By taking a break, nootropic users reduce the tolerance for nootropics and lessen the risk of regression and tolerance symptoms.