Microdosing with Iboga: Native to the rainforests in Central Africa, Iboga is an evergreen shrub, with high concentrations found in the root bark. It has a rich history amongst practitioners in the indigenous Bwiti religion in Africa and has recently found its way into Western practices, primarily for extremely effective therapy for drug addictions, but also for physical energy, cognitive performance in smaller microdoses, and a surge in positive emotions (See additional studies here and here.).  To microdose with Iboga, you will want to find it in tincture or root bark form (the root bark form is typically encapsulated). If using a tincture, find a source that has the root bark extracted into its purest form, combined with Iboga alkaloids, which keeps the full spectrum of the plant untouched. Just a single drop of an Iboga tincture equates to about 0.5 milligrams and suffices as a microdose. For the root bark of Iboga, a dose of 300-500 milligrams is also an effective dose. I’ve personally found Iboga to be most useful prior to a workout or an effort that combines both brain and body demands, such as tennis or basketball – but it makes you hyperactive and jittery if taken prior to a day of desk work. This makes sense when you consider that African tribes traditionally whipped themselves into a frenzied pre-battle state on Iboga.

Similarly, Mehta et al 2000 noted that the positive effects of methylphenidate (40 mg) on spatial working memory performance were greatest in those volunteers with lower baseline working memory capacity. In a study of the effects of ginkgo biloba in healthy young adults, Stough et al 2001 found improved performance in the Trail-Making Test A only in the half with the lower verbal IQ.
Notice that poor diet is not on the list. They recommend active treatment of hypertension, more childhood education, exercise, maintaining social engagement, reducing smoking, and management of hearing loss, depression, diabetes, and obesity. They do not recommend specific dietary interventions or supplements. They estimate that lifestyle interventions “might have the potential to delay or prevent a third of dementia cases.”

The evidence? Although everyone can benefit from dietary sources of essential fatty acids, supplementation is especially recommended for people with heart disease. A small study published in 2013 found that DHA may enhance memory and reaction time in healthy young adults. However, a more recent review suggested that there is not enough evidence of any effect from omega 3 supplementation in the general population.

Chocolate or cocoa powder (Examine.com), contains the stimulants caffeine and the caffeine metabolite theobromine, so it’s not necessarily surprising if cocoa powder was a weak stimulant. It’s also a witch’s brew of chemicals such as polyphenols and flavonoids some of which have been fingered as helpful10, which all adds up to an unclear impact on health (once you control for eating a lot of sugar).
I posted a link to the survey on my Google+ account, and inserted the link at the top of all gwern.net pages; 51 people completed all 11 binary choices (most of them coming from North America & Europe), which seems adequate since the 11 questions are all asking the same question, and 561 responses to one question is quite a few. A few different statistical tests seem applicable: a chi-squared test whether there’s a difference between all the answers, a two-sample test on the averages, and most meaningfully, summing up the responses as a single pair of numbers and doing a binomial test:
Is 200 enough? There are no canned power functions for the ordinal logistic regression I would be using, so the standard advice is to estimate power by simulation: generating thousands of new datasets where we know by construction that the binary magnesium variable increases MP by 0.27 (such as by bootstrapping the original Noopept experiment’s data), and seeing how often in this collection the cutoff of statistical-significance is passed when the usual analysis is done (background: CrossValidated or Power Analysis and Sample Size Estimation using Bootstrap). In this case, we leave alpha at 0.05, reuse the Noopept experiment’s data with its Magtein correlation, and ask for the power when n=200
I was contacted by the Longecity user lostfalco, and read through some of his writings on the topic. I had never heard of LLLT before, but the mitochondria mechanism didn’t sound impossible (although I wondered whether it made sense at a quantity level14151617), and there was at least some research backing it; more importantly, lostfalco had discovered that devices for LLLT could be obtained as cheap as $15. (Clearly no one will be getting rich off LLLT or affiliate revenue any time soon.) Nor could I think of any way the LLLT could be easily harmful: there were no drugs involved, physical contact was unnecessary, power output was too low to directly damage through heating, and if it had no LLLT-style effect but some sort of circadian effect through hitting photoreceptors, using it in the morning wouldn’t seem to interfere with sleep.
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.
The evidence? Ritalin is FDA-approved to treat ADHD. It has also been shown to help patients with traumatic brain injury concentrate for longer periods, but does not improve memory in those patients, according to a 2016 meta-analysis of several trials. A study published in 2012 found that low doses of methylphenidate improved cognitive performance, including working memory, in healthy adult volunteers, but high doses impaired cognitive performance and a person’s ability to focus. (Since the brains of teens have been found to be more sensitive to the drug’s effect, it’s possible that methylphenidate in lower doses could have adverse effects on working memory and cognitive functions.)
Is 200 enough? There are no canned power functions for the ordinal logistic regression I would be using, so the standard advice is to estimate power by simulation: generating thousands of new datasets where we know by construction that the binary magnesium variable increases MP by 0.27 (such as by bootstrapping the original Noopept experiment’s data), and seeing how often in this collection the cutoff of statistical-significance is passed when the usual analysis is done (background: CrossValidated or Power Analysis and Sample Size Estimation using Bootstrap). In this case, we leave alpha at 0.05, reuse the Noopept experiment’s data with its Magtein correlation, and ask for the power when n=200
The hormone testosterone (Examine.com; FDA adverse events) needs no introduction. This is one of the scariest substances I have considered using: it affects so many bodily systems in so many ways that it seems almost impossible to come up with a net summary, either positive or negative. With testosterone, the problem is not the usual nootropics problem that that there is a lack of human research, the problem is that the summary constitutes a textbook - or two. That said, the 2011 review The role of testosterone in social interaction (excerpts) gives me the impression that testosterone does indeed play into risk-taking, motivation, and social status-seeking; some useful links and a representative anecdote:
Barbara Sahakian, a neuroscientist at Cambridge University, doesn’t dismiss the possibility of nootropics to enhance cognitive function in healthy people. She would like to see society think about what might be considered acceptable use and where it draws the line – for example, young people whose brains are still developing. But she also points out a big problem: long-term safety studies in healthy people have never been done. Most efficacy studies have only been short-term. “Proving safety and efficacy is needed,” she says.

As it happens, these are areas I am distinctly lacking in. When I first began reading about testosterone I had no particular reason to think it might be an issue for me, but it increasingly sounded plausible, an aunt independently suggested I might be deficient, a biological uncle turned out to be severely deficient with levels around 90 ng/dl (where the normal range for 20-49yo males is 249-839), and finally my blood test in August 2013 revealed that my actual level was 305 ng/dl; inasmuch as I was 25 and not 49, this is a tad low.
Fortunately for me, the FDA decided Smart Powder’s advertising was too explicit and ordered its piracetam sales stopped; I was equivocal at the previous price point, but then I saw that between the bulk discount and the fire-sale coupon, 3kg was only $99.99 (shipping was amortized over that, the choline, caffeine, and tryptophan). So I ordered in September 2010. As well, I had decided to cap my own pills, eliminating the inconvenience and bad taste. 3kg goes a very long way so I am nowhere close to running out of my pills; there is nothing to report since, as the pills are simply part of my daily routine.
Of course, before wrapping up this section on psychedelics, I’ll address the topics of where to actually buy the stuff. There are a variety of websites that sell psychedelics, but not all ingredient, chemical or quality sourcing is created equal, nor is there any guarantee that any substance you are purchasing is not laced with undesirable compounds. Heck, I get my psilocybin from a farmer in Wisconsin who is a personal friend, and other ingredients from close acquaintances who have their own sources. I know it may seem unfair, but sometimes sourcing comes down to “who ya know” and doing your own due diligence on that person’s source.
One curious thing that leaps out looking at the graphs is that the estimated underlying standard deviations differ: the nicotine days have a strikingly large standard deviation, indicating greater variability in scores - both higher and lower, since the means weren’t very different. The difference in standard deviations is just 6.6% below 0, so the difference almost reaches our usual frequentist levels of confidence too, which we can verify by testing:
I took the pill at 11 PM the evening of (technically, the day before); that day was a little low on sleep than usual, since I had woken up an hour or half-hour early. I didn’t yawn at all during the movie (merely mediocre to my eyes with some questionable parts)23. It worked much the same as it did the previous time - as I walked around at 5 AM or so, I felt perfectly alert. I made good use of the hours and wrote up my memories of ICON 2011.

Oxidative stress refers to a biochemical process that occurs as a result of an accumulative everyday exposure to toxic burdens such as chemicals in cosmetics, furniture, paints, cars, and pollution. Our body has its own way of armouring itself from the damage that exposure to toxins can create through its production of endogenous antioxidants, which is nature’s way of neutralising oxidative stress. Although we have our own production of these wonder molecules, when we are continuously overloaded with toxins in our environment and have problems detoxifying, the liver can become overwhelmed. Research shows that over time oxidative stress can lead to an increase in inflammatory molecules such as cytokines, which have been shown to correlate with depression (5).This is why it is important to have a high intake of nutrients that support the liver in metabolising and removing toxins from the body, as well as regulating the inflammatory response. There are a few things we can change in our diet to support this area, for example eating foods such as the cruciferous family of vegetables which includes kale, cauliflower, broccoli and cabbage. These are particularly effective at supporting the liver in ushering out toxins as they all share an antioxidant compound called indole-3 Carbinol, which plays an important role in liver health (6). In addition, bitter greens such as collard greens, rocket, chicory and swiss chard are also great for supporting the liver’s own antioxidant defence system.

It’s a frosty Monday evening in March, but in the back of Idea Coffee, a dingy café near the Empire State Building, things are heating up. A group huddles around a small black box—the $160 ApeX Type A brain stimulator, with its retro-looking meter and dial and two electrodes. It’s supposed to bolster learning by delivering a mild electric current to the brain. The guy who’s been experimenting with it for a week notes that the only thing he’s noticed so far is a metallic taste in his mouth.
OptiMind - It is one of the best Nootropic supplements available and brought to you by AlternaScript. It contains six natural Nootropic ingredients derived from plants that help in overall brain development. All the ingredients have been clinically tested for their effects and benefits, which has made OptiMind one of the best brain pills that you can find in the US today. It is worth adding to your Nootropic Stack.

This tendency is exacerbated by general inefficiencies in the nootropics market - they are manufactured for vastly less than they sell for, although the margins aren’t as high as they are in other supplement markets, and not nearly as comical as illegal recreational drugs. (Global Price Fixing: Our Customers are the Enemy (Connor 2001) briefly covers the vitamin cartel that operated for most of the 20th century, forcing food-grade vitamins prices up to well over 100x the manufacturing cost.) For example, the notorious Timothy Ferriss (of The Four-hour Work Week) advises imitators to find a niche market with very high margins which they can insert themselves into as middlemen and reap the profits; one of his first businesses specialized in… nootropics & bodybuilding. Or, when Smart Powders - usually one of the cheapest suppliers - was dumping its piracetam in a fire sale of half-off after the FDA warning, its owner mentioned on forums that the piracetam was still profitable (and that he didn’t really care because selling to bodybuilders was so lucrative); this was because while SP was selling 2kg of piracetam for ~$90, Chinese suppliers were offering piracetam on AliBaba for $30 a kilogram or a third of that in bulk. (Of course, you need to order in quantities like 30kg - this is more or less the only problem the middlemen retailers solve.) It goes without saying that premixed pills or products are even more expensive than the powders.
l-Theanine – A 2014 systematic review and meta-analysis found that concurrent caffeine and l-theanine use had synergistic psychoactive effects that promoted alertness, attention, and task switching;[29] these effects were most pronounced during the first hour post-dose.[29] However, the European Food Safety Authority reported that, when L-theanine is used by itself (i.e. without caffeine), there is insufficient information to determine if these effects exist.[34]