Reason: Vitamin B12 supports brain health in critical ways. The water-soluble B vitamin helps the body convert carbohydrates and fats into energy the brain needs to function properly. It also helps reduce the brain shrinkage often associated with cognitive disorders, supports healthy sleep-wake cycles (incredibly important, given what we now know about sleep and Alzheimer’s risk), and aids the proper “firing” of communications between neurons.
It is at the top of the supplement snake oil list thanks to tons of correlations; for a review, see Luchtman & Song 2013 but some specifics include Teenage Boys Who Eat Fish At Least Once A Week Achieve Higher Intelligence Scores, anti-inflammatory properties (see Fish Oil: What the Prescriber Needs to Know on arthritis), and others - Fish oil can head off first psychotic episodes (study; Seth Roberts commentary), Fish Oil May Fight Breast Cancer, Fatty Fish May Cut Prostate Cancer Risk & Walnuts slow prostate cancer, Benefits of omega-3 fatty acids tally up, Serum Phospholipid Docosahexaenonic Acid Is Associated with Cognitive Functioning during Middle Adulthood endless anecdotes.
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As a student Seltzer used both Adderall and piracetam. Now, after a hiatus of several years, he has recently resumed taking neuroenhancers. In addition to piracetam, he took a stack of supplements that he thought helped his brain to function: fish oils, five antioxidants, a product called ChocoMind and a number of others, all available at the health-food store. He was thinking about adding modafinil, but hadn't yet. For breakfast every morning he concocted a slurry of oatmeal, berries, soy milk, pomegranate juice, flaxseed, almond meal, raw eggs and protein powder. The goal behind the recipe was efficiency: to rely on "one goop you could eat or drink that would have everything you need nutritionally for your brain and body. I wanted to be able to keep it down - that was it." (He told me this in the kitchen of his apartment; he lives with a roommate, who walked in while we were talking, listened perplexedly for a moment, then put a frozen pizza in the oven.)

Fitzgerald 2012 and the general absence of successful experiments suggests not, as does the general historic failure of scores of IQ-related interventions in healthy young adults. Of the 10 studies listed in the original section dealing with iodine in children or adults, only 2 show any benefit; in lieu of a meta-analysis, a rule of thumb would be 20%, but both those studies used a package of dozens of nutrients - and not just iodine - so if the responsible substance were randomly picked, that suggests we ought to give it a chance of 20% \times \frac{1}{\text{dozens}} of being iodine! I may be unduly optimistic if I give this as much as 10%.

The demands of university studies, career, and family responsibilities leaves people feeling stretched to the limit. Extreme stress actually interferes with optimal memory, focus, and performance. The discovery of nootropics and vitamins that make you smarter has provided a solution to help college students perform better in their classes and professionals become more productive and efficient at work.
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.
Colorful vegetables and fruits—such as leafy greens, peppers, beets, and berries—are high in carotenoids and anthocyanins, antioxidant pigments that provide their bright hues. “Antioxidants protect brain cell linings from the damage caused by free radicals, which are harmful molecules that cause inflammation and result from factors like a poor diet or smoking,” explains Janis Jibrin, RD, adjunct professor of nutrition at American University in Washington, D.C.
The benefit of sequential analysis here is being able to stop early, conserving pills, and letting me test another dosage: if I see another pattern of initial benefits followed by decline, I can then try cutting the dose by taking one pill every 3 days; or, if there is a benefit and no decline, then I can try tweaking the dose up a bit (maybe 3 days out of 5?). Since I don’t have a good idea what dose I want and the optimal dose seems like it could be valuable (and the wrong dose harmful!), I can’t afford to spend a lot of time on a single definitive experiment.

Turns out, when compared with smokers who drank coffee regularly, non-coffee drinkers had twice as much of the cell damage associated with tobacco use. In addition, the smokers who didn’t consume coffee were up to seven times more likely to be affected by the same cancer as nonsmokers. Regular smokers who drank coffee fewer than two times each week had double the chances of developing cancer compared to those who drank coffee frequently. So ultimately, coffee-drinking cigarette-puffers have some kind of health advantage over their smoking counterparts who don’t drink coffee.
Nootropics (/noʊ.əˈtrɒpɪks/ noh-ə-TROP-iks) (colloquial: smart drugs and cognitive enhancers) are drugs, supplements, and other substances that may improve cognitive function, particularly executive functions, memory, creativity, or motivation, in healthy individuals.[1] While many substances are purported to improve cognition, research is at a preliminary stage as of 2018, and the effects of the majority of these agents are not fully determined.