-Phosphatidylserine, which occurs naturally in high concentrations in the brain and has been shown to lower stress, cortisol and physical fatigue, improve attention-deficit and forgetfulness and increase mental processing and memory. Research indicates an effective dose of 100 mg three times daily, but anything over that may lead to adverse side effects like insomnia.
2 commenters point out that my possible lack of result is due to my mistaken assumption that if nicotine is absorbable through skin, mouth, and lungs it ought to be perfectly fine to absorb it through my stomach by drinking it (rather than vaporizing it and breathing it with an e-cigarette machine) - it’s apparently known that absorption differs in the stomach.
Finding a usable product on Amazon caused me some difficulties. I wanted a 500mg magnesium-citrate-only product at <$20 for 120 doses, but I discovered most of the selection for magnesium citrate had sub-500mg doses, involved calcium citrate or other substances like zinc (not necessarily a bad thing, but would confound an experiment), were mostly magnesium oxide rather than citrate, or some still other problem. Ultimately I settled on Solgar’s $13 120x400mg magnesium citrate as acceptable. (To compare with the bulkiness of the LEF vitamin D+l-threonate powder, the Office of Dietary Supplements says magnesium citrate is 16% magnesium, so to get 400mg of magnesium as claimed, would take 2.5g of material, rather than 7g for 200mg; even if l-threonate is absorbed 100% and citrate 50%, the citrate is ahead. The pills turn out to be wider and longer than my 00 pills; if I want to get them into my gel capsules, I have to crush them into fine powder. The powder from one pill turns out to take up 2 00 pills.)
As a general class, nootropics are not usually addiction-forming.[6] Two of the strongest hallmarks of addiction-forming drugs is that they cause users to develop dependency and experience withdrawal when the drug use is eliminated or reduced. While there are some reports of nootropic users experiencing brain fog after use is discontinued, these side effects are not considered to be akin to withdrawal effects of addiction-forming drugs.[7]
The desire to improve cognitive functioning has probably existed since the dawn of human consciousness. Throughout our evolution, increased mental agility has been associated with fitness and improved odds of survival and success. Although concoctions to stimulate brainpower have existed in Chinese and Indian medicine for hundreds of years, Western nootropics were not developed until 1964.

The fact of the matter is, though, that the phrase ‘best brain pill’ doesn’t cover any of the bases you’d want an informative article to cover. The human brain is a large and complex thing, and there are many different kinds of pills, supplements, and medications that you can take to improve or affect different areas and functions. Many more of those pills, supplements and medications you take when it breaks down or glitches, to help control harmful or disorienting symptoms of various mental diseases.
These are the most highly studied ingredients and must be combined together to achieve effective results. If any one ingredient is missing in the formula, you may not get the full cognitive benefits of the pill. It is important to go with a company that has these critical ingredients as well as a complete array of supporting ingredients to improve their absorption and effectiveness. Anything less than the correct mix will not work effectively.

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.).
Because smart drugs like modafinil, nicotine, and Adderall come with drawbacks, I developed my own line of nootropics, including Forbose and SmartMode, that’s safe, widely available, and doesn’t require a prescription. Forskolin, found in Forbose, has been a part of Indian Ayurvedic medicine for thousands of years. In addition to being fun to say, forskolin increases cyclic adenosine monophosphate (cAMP), a molecule essential to learning and memory formation. [8]

Adderall is a mix of 4 amphetamine salts (FDA adverse events), and not much better than the others (but perhaps less addictive); as such, like caffeine or methamphetamine, it is not strictly a nootropic but a cognitive enhancer and can be tricky to use right (for how one should use stimulants, see How To Take Ritalin Correctly). I ordered 10x10mg Adderall IR off Silk Road (Wikipedia). On the 4th day after confirmation from seller, the package arrived. It was a harmless looking little padded mailer. Adderall as promised: 10 blue pills with markings, in a double ziplock baggy (reasonable, it’s not cocaine or anything). They matched pretty much exactly the descriptions of the generic I had found online. (Surprisingly, apparently both the brand name and the generic are manufactured by the same pharmacorp.)

One thing I notice looking at the data is that the red magnesium-free days seem to dominate the upper ranks towards the end, and blues appear mostly at the bottom, although this is a little hard to see because good days in general start to become sparse towards the end. Now, why would days start to be worse towards the end, and magnesium-dose days in particular? The grim surmise is: an accumulating overdose - no immediate acute effect, but the magnesium builds up, dragging down all days, but especially magnesium-dose days. The generally recognized symptoms of hypermagnesemia don’t include effect on mood or cognition, aside from muscle weakness, confusion, and decreased reflexes…poor appetite that does not improve, but it seems plausible that below medically-recognizable levels of distress like hypermagnesemia might still cause mental changes, and I wouldn’t expect any psychological research to have been done on this topic.

The bitter reality of life is that there’s no organ of our body, which can defy the effects of aging with success. At least not entirely on its own. That’s why we need supplements in the first place. Remember? That’s only the beginning of the bad news for your brain. Certain sections of our brain, especially prefrontal cortex and hippocampus, can be seriously reduced in size as you are getting older. In addition, the number of capillaries in your head reduces, as well. Let’s not forget the arteries that become narrower and therefore limit the blood flow.
One of the most obscure -racetams around, coluracetam (Smarter Nootropics, Ceretropic, Isochroma) acts in a different way from piracetam - piracetam apparently attacks the breakdown of acetylcholine while coluracetam instead increases how much choline can be turned into useful acetylcholine. This apparently is a unique mechanism. A crazy Longecity user, ScienceGuy ponied up $16,000 (!) for a custom synthesis of 500g; he was experimenting with 10-80mg sublingual doses (the ranges in the original anti-depressive trials) and reported a laundry list of effects (as does Isochroma): primarily that it was anxiolytic and increased work stamina. Unfortunately for my stack, he claims it combines poorly with piracetam. He offered free 2g samples for regulars to test his claims. I asked & received some.

Thanks to the many years of research in the field, we know now that what we eat can have a strong impact on our mental health. Not only can it protect us from developing Alzheimer's, but it's an act of self-care on its own. "Biology is all about harmony, about finding equilibrium and homeostasis," says Dr. Lisa, which is why her approach differs from food restrictions and focuses on minimizing intake of those foods that don't help us feel better. 
[…] The 7 Best Brain Boosting Supplements | Live in the Now … – These same lifestyle changes also protect you from heart disease and diabetes—two 21st century killers that can wreak havoc … Phosphatidyl Serine and Coenzyme Q10. Opt for the best brain supplements and stay fit with an active brain. You should be very careful while choosing the right … […]

For now, instead of reaching for a designer supplement, you're better off taking a multivitamin, according to some experts. It's well known that antioxidants like vitamins C and E protect cells from damage by disarming free radicals. Brain cells are especially vulnerable to these troublemakers because the brain generates more free radicals per gram of tissue than any other organ. Antioxidants also protect neurons by keeping blood vessels supple and open, ensuring the flow of nutrients to the brain.

The experiment then is straightforward: cut up a fresh piece of gum, randomly select from it and an equivalent dry piece of gum, and do 5 rounds of dual n-back to test attention/energy & WM. (If it turns out to be placebo, I’ll immediately use the remaining active dose: no sense in wasting gum, and this will test whether nigh-daily use renders nicotine gum useless, similar to how caffeine may be useless if taken daily. If there’s 3 pieces of active gum left, then I wrap it very tightly in Saran wrap which is sticky and air-tight.) The dose will be 1mg or 1/4 a gum. I cut up a dozen pieces into 4 pieces for 48 doses and set them out to dry. Per the previous power analyses, 48 groups of DNB rounds likely will be enough for detecting small-medium effects (partly since we will be only looking at one metric - average % right per 5 rounds - with no need for multiple correction). Analysis will be one-tailed, since we’re looking for whether there is a clear performance improvement and hence a reason to keep using nicotine gum (rather than whether nicotine gum might be harmful).
However, anthropology suggests that paleolithic diets were dependent of where people lived. Close to shores, they ate more fish; within the forest they ate plants; in areas with herbivores they ate more meat. Also, humans ate grains millions of years before the agricultural revolution. And, we can digest those just fine because of an enzyme earmarked to digest grains (amylase). So, paleolithic diets were as varied as they are today.
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]