Nootropics are substances that purport to improve cognition and concentration. In other words, they're supposed to help you think better. But do nootropics actually do that?

The answer is a combination of "sometimes" and "maybe" with a side of "well, not by much." It's easy to get your hopes up that the next pill or powder you try will be the one that makes you a thousand times more productive, but only the lucky psychoactive dabblers see even a marginal improvement.

Still, nootropics are an evergreen staple of Silicon Valley trend stories. Media outlets ran stories in 2015, 2016, and certainly 2017 (a handful out of many examples), alongside coverage of Bulletproof coffee as well as ketogenic and even carnivorous diets. Techie self-tinkering is irresistible to reporters, including myself, because it's appealingly weird.

Unregulated experimental supplements have been buzzed about for years, but they have yet to deliver the radical results that techno-futurists have been salivating for. As a would-be brain enhancer myself, I can sadly report that my sci-fi dreams fell by the wayside once I learned more about the actual experience of using nootropics.

Last week, CNBC reported that the startup formerly known as Nootrobox, now called HVMN, found that its vaunted SPRINT supplement wasn't able to outperform plain old caffeine in clinical trials. It's tempting to blame HVMN individually, especially since the company scrambled for distance from the study after learning of the dissatisfactory result, according to CNBC. Of course, the underwhelming performance of SPRINT specifically can't indict the many nootropic substances that it didn't contain (such as racetams and modafinil, both well-known and backed by extensive research).

And yet, as a jaded consumer, I hope that HVMN's reckoning will serve to remind everyone that we need to temper our expectations for nootropics. Limitless was, alas, not a documentary. HVMN exemplifies the reality of an industry where hype continues to outpace science.

In fact, the most popular and widely used nootropic is caffeine, although your morning cup of coffee probably doesn't feel like a revolutionary brain-boosting drug. Most caffeine users don't consider it biohacking because it's so normal, which is the decidedly unreached goal for all nootropics.

This is not to say that nootropics do nothing. Rather, the best-case scenario for nootropics is akin to taking creatine to build muscles, rather than a pro bodybuilder's drug regimen: You might have marginally better results than you would otherwise, but it won't be anything revolutionary.

A popular blog called Slate Star Codex, which conducted a nootropics survey in 2016, warned readers this year that "the benefits [of nootropics] are usually subtle at best." The author further cautioned, "[I]f some stimulant product combines caffeine with something else, and you feel an effect, your first theory should be that the effect is 100% caffeine -- unless the 'something else' is amphetamine." And even caffeine comes with downsides: It's addictive, has diminishing returns, and makes many people jittery or irritable.

Independent researcher Gwern Branwen, who has experimented with nootropics extensively, wrote that "it is curious that despite the incredible progress mankind has made in countless areas like building cars or going to the moon or fighting cancer or extincting smallpox or inventing computers or artificial intelligence, we lack any meaningful way to positively affect people's intelligence beyond curing diseases & deficiencies."

Branwen added a rueful analogy: "It is as if scientists and doctors, after studying cars for centuries, shamefacedly had to admit that their thousands of experimental cars all still had their speed throttles stuck on 25-30kph -- but the good news was that this new oil additive might make a few of the cars run 0.1kph faster!"

On his main nootropics page, Branwen wrote, "The best you can do is read all the testimonials and studies and use that to prioritize your list of nootropics to try. You don't know in advance which ones will pay off and which will be wasted. You can't know in advance." I'd add that also can't know whether any of the nootropics you try will work at all. There are no guarantees, and certainly no One Weird Trick! that will make your brain amazing.