“why would you noot ropics? ”

I t ’s l i ke, OK, go to work without your laptop— do that? Go to work without taking What ’ s the advantage of that?

It’s 8 a.m. on a recent Wednesday in San Francisco, and Yan Zhu, a 24-year-old blue-haired software engineer, sits at a communal table in a Thai-italian restaurant munching on a stick of butter. She’s too hungry to wait for food; she hasn’t eaten in 36 hours. “This is my first time fasting, and I was feeling faint, so I brought some butter from home,” Zhu says. Her friend Ayumi Yu (pink hair, 27) explains they’re on a ketogenic diet, which requires eating mostly fat and almost no carbohydrates. “I’ve been on it for a month and feel amazing,” she says. “Take how you feel and imagine feeling twice as good.” Danny Friday, a 23-year-old startup founder, emerges from the bathroom. He’s just done a urine test to check his ketosis levels, which indicate how the body is metabolizing fat. “I’m shocked,” he says, dismayed. “My body is barely in ketosis.”

All three, along with about 25 other people, are here to take part in a weekly break fast. The hosts, Geoffrey Woo and Michael Brandt, are the 27-year-old co-founders of Nootrobox, a startup that sells “nootropics,” or pills intended to enhance memory, cognition, and mental stamina. Although fasting is not necessarily part of a nootropic regimen, the widely accepted healthboosting effects of periodic starvation make it a natural fit for people who think a monthly pill subscription service can make them more perfect humans. “We’ll do a 36-hour or 60-hour fast every week,” says Woo, Nootrobox’s chief executive officer. “It’s hard at first, but we found a lot of benefit to our lucidity and clarity of mind.” The company’s online fasting forum, Wefast, has about 600 members.

Nootrobox’s mission is to improve the way we function on a daily basis. “In the office of the future, people will get to work, sit down, and pop a pill to help them focus better,” says Brandt, Nootrobox’s chief operating officer. When that future will arrive is unclear. But if office drones are already willing to give up their lunch break to slurp Soylent, what’s to say they wouldn’t like to benefit from other efficiencies? Many already bend the truth with their doctors to score Adderall. Nootrobox is just targeting the vast pool of upwardly mobile professionals who want an edge but may not be ready to commit to prescription drugs, Woo says. Perhaps this is why he and Brandt have been able to persuade some heavy hitters in Silicon Valley to invest in their vision, including Yahoo! CEO Marissa Mayer, Zynga Executive Chairman Mark Pincus, and venture capital firm Andreessen Horowitz, which led a $2 million funding round that closed in October. (Bloomberg LP, which owns Bloomberg Businessweek, is an investor in Andreessen Horowitz.) Woo says only that Nootrobox, with its thousands of monthly subscribers, is a “multimillion” dollar business, but he declines to elaborate.

For two fasting workaholics, Woo and Brandt look healthy. The friends and roommates met as undergrads at Stanford, where they majored in computer science and bonded by trading self-improvement tips. After college, Woo founded a locationtracking company that Groupon later acquired; Brandt joined then-google COO Mayer’s elite associate product manager program. In 2014 they got into the nootropics business. “Friends were playing around with Adderall and smart drugs,” Woo says. Some were even ordering nootropic powders online and mixing their own concoctions. “They literally have a drug scale and are weighing out, like, 50 milligrams of powder in their kitchens— it’s messy,” he says. “We realized that if people are willing to go through this much trouble, this much sketchiness to tap this resource, there must be something there.”

Brandt and Woo read studies and began experimenting with nootropic powders available online. Some had unexpected side effects. “I tried noopept, a Russian Alzheimer’s therapeutic,” Woo says. The drug made him alert—but it also altered his sensory perception. “I remember walking to the BART, the public transit system in San Francisco, and the flowers on the side of the road, daffodils, looked really bright.” In the end, the co-founders decided not to sell a product that triggered mild hallucinations and, instead, to work with supplements approved by the U.S. Food and Drug Administration. “You can’t make a business selling illegal, gray-area stuff,” Woo says.

Nootrobox’s office, in a corner of a Wework co-working space in the Soma neighborhood, is covered in slogans such as “Hustle Harder.” The company’s products, formulated using a combination of peer-reviewed studies and “bro science,” are as prevalent as imacs. There’s Rise ($44 for 60 pills), which touts a ratio of compounds shown in studies to improve memory; Sprint ($36 for 30), packed with B vitamins, caffeine, the caffeine-enhancing amino acid L-theanine, and inositol, which mitigates panic attacks; and Yawn ($36 for 30), which makes it easier to sleep after a day of downing the other two. Go Cubes are essentially gummy versions of Sprint. Two cubes have 100mg of caffeine, equivalent to about a cup of coffee—“except with coffee, you have no idea how much caffeine you’re getting,” Woo says, explaining that levels vary by bean and brewer. His Twitter wallpaper reads, “Coffee Is Dead. Long Live Go Cubes.”

The pills are intended to be “stacked,” a term taken from bodybuilding that means pairing synergistic substances to achieve a desired outcome. All eight employees, including three M.D.-PH.D. candidates, stack the pills and Cubes daily, even while fasting. “I can’t imagine going back to life” without nootropics, Brandt says. “It’s like, OK, go to work without your laptop—why would you do that? Go to work without taking nootropics? What’s

Founders Brandt and Woo (far right) with Nootrobox staff