The teenage hormone that triggers puberty and prevents cancer

The appropriately named kisspeptin was discovered by accident, and has some surprising effects.

Whatever your parents told you, it’s not about the birds and the bees. Ultimately, reproduction seems to be about a protein molecule called kisspeptin. The name has nothing to do with foreplay, however. Kisspeptin was discovered in Hershey, Pennsylvania, and its name comes from the town’s other great research success: Hershey’s Kisses chocolates.

At some point, most people’s brain starts to secrete kisspeptin; when it does, the hypothalamus begins to produce a chemical called gonadotropin-releasing hormone, or GnRH. Written down, it looks like a teenage grunt and that’s what it leads to. GnRH release is a crucial moment at the beginning of puberty. It brings about the secretion of hormones that start egg or sperm production and create the characteristic signs of sexual maturity.

On 12 September, the King’s College London professor Kevin O’Byrne discussed the “enigma” of GnRH at a conference at the University of Bristol. The central enigma is the unanswered question of what kicks off puberty – we still don’t know what activates kisspeptin to release GnRH.

It seems to have something to do with the brain’s monitoring of stress and nutrition. Without good fat reserves and a relaxed demeanour, the chemical sages won’t let you enter the trials of reproduction. That’s why girls suffering from anorexia can experience disrupted menstruation.

Kisspeptin’s role in puberty was discovered by accident when researchers were looking at its anti-cancer properties. Controlling the teenage brain is not the only thing it can do. GnRH is now used as a part of some cancer treatment routines because it stops the production of oestrogen, a hormone that seems to play a role in stimulating tumour growth.

Here’s another clue: some of the ugliest rodents on the planet, known as “naked mole rats”, are awash with kisspeptin – and they don’t get cancer.

Most animals have levels of kisspeptin neurons that vary according to sex as well as reproductive state. New research shows that naked mole rats have high kisspeptin and GnRH levels no matter what their readiness for reproduction.

That is particularly odd because, despite these high levels of kisspeptin, most naked mole rats don’t develop the ability to breed. Like some species of bee, naked mole rats live in colonies in which only a queen and a few consorts develop the ability to reproduce. The rest are workers that remain sterile all their lives. And those are long lives.

Their extraordinary resistance to developing cancers makes naked mole rats the longestliving rodents. Mice and rats typically live for two or three years; naked mole rats often live for two decades or more. Understanding what kisspeptin does for the naked mole rat could assist our fight against the ravages of ageing.

However, our slowly increasing grasp of kisspeptin and GnRH is causing a dilemma. The age at which human beings hit puberty is falling – on average, it has fallen by five years since 1920. It’s less of a problem for boys than for girls, for whom “precocious puberty” is linked with an increased risk of breast cancer, mental disorders and, in later life, polycystic ovary syndrome.

That raises the question of whether we should intervene. There’s still a lot we don’t know but research has shown that an injection of kisspeptin kicks off puberty artificially. More usefully, drugs that block kisspeptin prevent puberty from starting and doctors are starting to intervene in the most extreme cases of precocious puberty. Some see this as a risky thing to do when we have no long-term data on the outcome.

This new branch of science might not yet have hit puberty but it is already starting to give us trouble.

Teenage kicks: Kisspeptin not only triggers puberty but also helps fight cancer

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 23 September 2013 issue of the New Statesman, Can Miliband speak for England?

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Forget “digital detoxes”. Spring clean your online life instead

Step one: remove the app on your phone which takes up the most time. 

In 2006, news broke that broke me. The British Heart Foundation unveiled a poster of a blonde girl guzzling a gallon of cooking oil. “What goes into crisps goes into you,” it read, as the charity declared that eating one packet of crisps a day equated to drinking five litres of oil a year.

I gave up crisps that Lent (an admirable act that was somewhat mitigated by devouring a six-pack of McCoy’s on Easter Sunday). Still, despite my continuing pack-a-day habit, the BHF’s statistic has never left me: 365 packets of salt and vinegar crisps are equal to five bottles of Filippo Berio. But other bad habits are harder to comprehend. Last week, I “liked” 36 things on Facebook, wrote ten tweets, and posted five Instagram pictures (two of which were selfies). What effect, if any, has this had on my mental and physical health? How much metaphorical cooking oil am I pouring into my body?

“You really don’t need to worry about the volume of your own social media interactions, based on the average digital user,” the founder of the digital detox specialists Time To Log Off, Tanya Goodin, told me. Goodin says that we “tap, click and swipe” our devices over 2,617 times a day and that the average person will post 25,000 selfies in their life.

Though these statistics seem shocking, what do they mean? What does swiping thousands of times a day do to our minds – or, for that matter, our thumbs? The experts are divided. In 2015, national newspapers spread stories suggesting that using an iPad would damage a toddler’s brain but the research didn’t mention the term “brain damage” once. In fact, as the Guardian pointed out in its debunking, studies produce mixed results: some say iPads help improve child literacy, others say they are distracting.

The studies about adults’ screentime are similarly hard to decipher. Heavy Facebook usage has been linked to depression but there isn’t any apparent cause and effect. Do depressed people use Facebook more, or does Facebook make us depressed? “Internet addiction disorder” (IAD) was a term originally coined as a hoax, but many now see it as a real and treatable problem. Yet it does not feature in the Diagnostic and Statistical Manual of Mental Disorders, and experts still struggle to set diagnostic criteria for it. How much internet is too much?

These academic ambiguities haven’t stopped the idea of the “digital detox” taking off. Detoxers refrain from using any electronics for a period of time in the hope that this will improve their mental health and real-world relationships. At the time of writing, if you search for “digital detox” on Instagram, you’ll find 25,945 people talking about their personal attempts. There are pictures of bike rides, sunsets and children playing, each posted – apparently without irony – to extol the virtues of getting off social media and turning off your phone.

Digital detoxing is also big business. Goodin runs workshops, retreats and camps where no electronics are allowed and the daily schedule consists of yoga, walking, swimming and drinking smoothies. The next one, in Italy, costs from £870 per head for a week. A multitude of such camps exist, as well as books, websites and guides on how to detox by yourself. To connect, man, you have to disconnect, you know?

All of this has made me a digital detoxing cynic. I don’t believe I need to switch off my phone to “live” better, because I believe my phone itself contains life. On Reddit, I can speak to strangers living hundreds of thousands of miles away about their lives. On Twitter, I can keep up to date – in real time – with news and events. If I want to learn yoga or make a smoothie, where will I go to find my local gym or the correct strawberry-to-spinach ratio? Technology can even inspire us to “get out more”. Last summer, the gaming app Pokémon Go spurred people to walk 2,000 more steps a day, and I’m willing to bet that brunch sales figures have skyrocketed since the invention of Instagram.

Digital detoxing relies on the vague idea that tech is somehow toxic. Even without scientific studies to back this up, most of us know from our own, anecdotal evidence how spending too much time on our phones can make us feel. We get down if our latest status doesn’t have enough likes, or our eyes hurt after the sixth “EXTREME PIMPLE POPPING” YouTube video in a row. So, at core, digital detoxing isn’t “wrong”: it is merely misguided. Instead of trying to cut out all technology for a week, we should be curbing our existing habits; rather than a digital detox, we should have a digital spring clean.

Delete – or hide – anyone on your Facebook friends list that you wouldn’t talk to in real life. Remove your work email from your phone (or ask your boss for a separate work phone if you absolutely need access). Delete the app that takes up most of your time – be it Facebook, Twitter or YouTube – so that you are forced to get to it manually, through your browser, and therefore become instantly more aware of how many times a day you open it up. Tanya Goodin also advises me to use my phone less at night. Essentially: go mild turkey. If this is too much and you believe you are addicted to your smartphone or laptop, then, of course, you should seek help (speak to your doctor or call the Samaritans on 116 123).

But most of us just need to get smarter about our internet use. Even if scientists proved that technology was damaging our brains, a week-long detox wouldn’t be the cure. Rather, we should focus on our bad personal habits and try to curb them. Do you get into too many arguments online? Do you ignore your partner because you’re staring at a screen? Do you post opinions you regret because you don’t think them through first? These behaviours are problematic – the internet itself isn’t. To control our lives, we shouldn’t switch off: we should get more switched on.

Amelia Tait is a technology and digital culture writer at the New Statesman.

This article first appeared in the 06 April 2017 issue of the New Statesman, Spring Double Issue

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