black&white #09: The caffeine high: friend or frenemy?

5 min steep

This week two articles caught my attention – and my imagination. Both are written by the brilliant author Michael Pollen, who has long investigated the intriguing relationship between human and nature: in our farms and gardens, on our plates, and, more recently, in our minds. His new book, This is Your Mind on Plants, explores the curious – and genetically strategic – ability of plants to alter our consciousness.

Caffeine is the most widely used psychoactive drug in the world. That makes sense, as the most popular drink in the world (after water) is tea, followed by coffee. Whether it’s good for you or not has long been contested, with some studies suggesting that high levels of caffeine consumption can lead to health problems. Like hundreds of other commonly consumed chemicals, it was classed by the World Health Organization as a potential carcinogen when consumed in large amounts. Stoked by the media, the anti-caffeine hype began to gain traction. But, more recent reviews of the evidence have shown that moderate amounts of caffeine consumption actually reduced the risk of heart disease and even high levels of caffeine-consumption did not pose any serious problems. In fact, as Pollan points out, caffeine has been cleared of most of the charges laid against it, instead offering some important health benefits. Reduced risk of several cancers, cardiovascular disease, type 2 diabetes, Parkinson’s disease and dementia have all been associated with moderate caffeine consumption. On both a personal and professional level this is good to know. 

Caffeine also helps improve brain function, such as memory, focus, attention and learning. An experiment done in the 1930s even found that chess players on caffeine performed significantly better than those who weren’t. Pollan also draws fascinating links between the Age of Enlightenment and the introduction of Arab-style coffee houses in Europe, which became centres of debate and intellectualism in the 17th and 18th centuries. So, what’s the problem? Well, caffeine can affect both the quality and quantity of sleep you get – which in turn can lead to a deluge of other health problems. Of course, caffeine is not solely responsible – screens, alcohol, work schedules, light pollution, noise and anxiety all play their part. But as Pollan so eloquently puts it, “here’s what’s uniquely insidious about caffeine: the drug is not only a leading cause of our sleep deprivation; it is also the principal tool we rely on to remedy the problem”.  

But hang on a mo. I figure that relates more to coffee/caffeine addiction than us tea enthusiasts. According to Matt Walker, neuroscientist at the University of California, the “quarter life” of caffeine for most people is about 12 hours, which means that 25% of the caffeine in a cup of coffee will still circulate in the brain 12 hours later. OK, that seems high, but (as a v rough assumption)a cup of black tea has on average less than half the amount of caffeine than a cup of coffee. And more reassuringly for tea drinkers, whole leaf green, oolong and white teas contain even less caffeine in the cup as they are bigger leaves and made cooler so release less caffeine. They also have high levels of L-theanine, an amino acid which reduces stress and anxiety, and helps you relax. And of course, herbals contain no caffeine whatsoever. I wake up with black tea and often move to green, oolong or white teas during the day, and always have a herbal infusion just before bed. The occasional coffee features, but only when made by friends who also happen to be World Champion baristas - seriously.

Pollan points to the ability of plants to mindbend, to truly alter human consciousness. For example, researchers have recently discovered that a number of flowering plants, including some citrus trees, produce caffeine in their nectar. That’s because our beloved honey bees actually prefer blossoms with a shot of caffeine – and are more likely to remember and return to the flowers that provide it. Incredibly, caffeine does the same thing for bees as it does for us: we become more efficient workers. Even more remarkably, the plants are the main beneficiaries as the bees become so hooked on caffeine that they return to the blossoms long after the nectar’s gone, cutting into important honey production time. I guess a bit like former days when we spent time hanging out in the office kitchen and not at our desks.

You can find Michael Pollan’s articles on The Intoxicating Garden here and The Invisible Addiction here.