Silicon Valley, the home of tech disruption and birthplace of Facebook, Uber and Airbnb, is full of people who want to optimise, adapt and reinvent processes and industries. Now, biohacking – the practice of manipulating your body’s biology to aid performance – is gaining traction there. It seems unsurprising; if your life revolves around optimisation, it follows that this might also extend to the human body and brain.

Biohacking is taking two distinct forms in the Valley: extreme fasting, when a person refrains from eating for up to 60 hours; and the use of ‘brain drugs’ – or mind enhancers – to boost memory and cognitive performance. Both have proponents in search of a means to rewire their body’s physiological and neurological systems to prime them for productivity. 

Self-improvement isn’t a new phenomenon. People have been fasting for years for weight loss, while drugs such as modafinil have been used by some to boost concentration. However, this trend towards fasting and taking cognitive drugs is focused on increasing productivity and concentration – a psychological desire for optimum performance. With several high-profile advocates openly discussing the benefits, the trend is showing no signs of slowing down. 

Hayley Ard, head of consumer lifestyle at research and trends consultancy Stylus, says biohacking is seen as a “shortcut to enlightenment”. “Silicon Valley has a high concentration of entrepreneurs who are looking to boost their focus and stimulate their minds,” she says. “In this competitive market, where performance is everything, biohacking has broad appeal.”

Fasting community WeFast has 1,200 online members and holds regular meetings in San Francisco to mark the end of fasting periods with a group meal. Meanwhile, entrepreneur Dave Asprey has turned his faith in the cognitive-boosting effects of buttered coffee into a lifestyle brand, with Bulletproof coffee.

Loïc Le Meur, co-founder of LeWeb tech conference, decided to start fasting after reading about the health benefits. He says refraining from the consumption of food and alcohol is “intense”, but that he feels “incredibly good” each time he does it. He adds: “It is also a great exercise of will that goes perfectly with my meditation practice.”

He is comforted by thinking of the human species during prehistoric times, when fasting was a normal part of existence. He says: “People were hunting and could not find any food for days or weeks. They were fasting all the time. Then they would kill a big animal and eat it, then fast again. Our bodies have been used to fasting since the dawn of time. It seems natural to me. Eating a big meal three times a day, with snacks in between, doesn’t.”

Research on the benefits of fasting has, historically, focused on the effect on the body, but recent studies have suggested there could also be neurological benefits to not eating.

Neuroscientist Mark Mattson’s experiments on mice, for example, found that intermittent fasting protected the animals from neurodegenerative diseases and extended their life spans by 30%. Fasting on alternate days, the researchers found, increased the production of proteins that protect brain cells, enhancing their ability to repair damaged DNA. Scientists at the Buck Institute, meanwhile, found that nutrient scarcity reduces synaptic activity, which could allow the brain to recharge itself.

However, these studies have been focused on animals, not humans – and although there is a lot of anecdotal evidence from proponents, nutritionist Jo Travers says scientific proof is lacking.

“Some people swear blind that it has given them super-human clarity in their thoughts, but real evidence is almost non-existent,” she says. “If it turns out it really does increase their productivity, maybe it will make it into mainstream advice eventually. But there is a risk that it won’t actually work, and these people may end up malnourished or tired. They may also end up in the opposite state – not concentrating because they are so hungry.” 

Travers adds that daily vitamin intake is important, and that supplements are not always absorbed by the body in the same way as food, so may not be an adequate replacement. 

She is also sceptical about the efficacy of cognitive enhancers. “While there may be evidence that B vitamins help cell division – including brain cell division – there is little evidence that taking a supplement will improve cognitive abilities and productivity,” she says.

Such products often contain caffeine, which has long been associated with improved concentration and memory. “But people have been doing that for centuries, so there’s nothing new there,” adds Travers. Ard, however, predicts that biohacking products will become as widespread as coffee, as people look to compete with automation in the future employment market. “I wouldn’t be surprised to see nootropic [smart drug] blends on the menu at chains such as Pret a Manger in the near future.”

She refers to American company Hvmn, formerly known as Nootrobox, where some employees take part in weekly 60-hour fasts and are fitted with glucose-monitoring implants to track blood-sugar level spikes. “Bio-sensors like this could have the power to monitor workers’ wellbeing on an intimate level. Although these systems would require consent, they could become psychological game changers.”

The trend of biohacking raises questions about the value individuals – and organisations – place on productivity. 

Niketa Kumar is a San Francisco-based psychologist who specialises in working with under-represented populations, particularly in tech. She is concerned by the trend – particularly prevalent in Silicon Valley – of prizing that which can be quantified above all else. 

“I worry that the immeasurable values of life – kindness, compassion, respect for one another, social and moral responsibility – are pushed to the wayside. Values are an important part of private and public life. What suffers when we prioritise measurable output and a bottom line above all else? Most things that matter. Increased productivity, when at the expense of the other, immeasurable, qualities of life, will not make you feel good long term. 

“If you value productivity because it allows you to provide for yourself and your loved ones, spend more time with the people you love, or do things that bring your life meaning, that is very different from valuing productivity for the sake of productivity. In the latter, you are saying: ‘My value comes from how much I produce.’ Then you’re in a precarious situation because, someday, you may not be able to work – and then what?”