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Got a cold? Eat caterpillars

Why medinical zinc is not all it's cracked up to be.

How’s this for impact? At the end of January, a research group in Manchester published a paper on the essential role of zinc in the human immune system. A week later, the price of zinc rose on the international metals markets after its longest slump in 25 years.

Amazing? Of course not. These are two entirely unrelated events. But it’s the ability to separate coincidence from causality that allows us to distinguish old wives’ tales from useful information.

Zinc has been in medical use since at least the 2nd century BC. A set of pills found in the remains of a ship wrecked off the Tuscan coast in 140BC are 75 per cent zinc. They were almost certainly used to treat eye and skin disorders, a practice documented by the Roman polymath Pliny in the 1st century AD.

Zinc is still used for this purpose. It has antiseptic and antiviral properties, which is why it is often embedded in dressings for wounds. What’s more, anecdotal evidence has long suggested that taking zinc supplements helps fight the common cold. But anecdotal evidence isn’t the most trustworthy: sometimes it sees cause and effect where there is none.

Even individual studies haven’t been enough to give us the answer; depending on how they are carried out, they can produce conflicting results. Fortunately, we’ve developed even more sophisticated techniques: dissection, analysis and pooling of the scientific studies themselves. This has allowed us to draw a firm and reliable conclusion. In the case of zinc, it’s this: take at least 75mg a day and “there is a significant reduction in the duration of cold”, according to a gold-standard Cochrane Review, which looks at primary research in health care. Ancient wisdom, in this case, has some validity.

What the ancients didn’t know is the mechanism involved. Zinc deficiency, it turns out, causes more than 3,000 types of protein in the body to function inefficiently or not at all. The body responds to this as stress, causing the immune system to leap into action. Specifically, according to researchers at Manchester University, zinc deficiency unleashes a molecule called interleukin-1-beta. This is part of the armoury of the immune system. The trouble is that, in the absence of any infection to clear, firing the immune response’s weaponry just causes damage.

The zinc deficiency, as the researchers point out, could easily be resolved using dietary supplements. And this increased medical use of zinc could have an economic impact.

Not, it has to be said, in the metals markets, where the rising price of zinc is linked to China’s construction boom. But zinc use for medical purposes could be worth about $25bn a year in the US alone. That is the estimated annual impact of common colds, in terms of lost productivity. The Cochrane Review has found that taking zinc supplements for at least five months can reduce that. It certainly reduces school absences and the prescription of antibiotics for children with the common cold.

Because colds are caused by a virus, antibiotics do nothing for sufferers, yet doctors prescribe them as a placebo to get worried parents out of their surgery. So zinc supplementation also slows the spread of antibiotic resistance. Here’s a final tip in case the price of zinc lozenges skyrockets: a daily 100g of cooked caterpillars contains all the zinc you need.

You’re welcome.
 

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 19 February 2014 issue of the New Statesman, The Space Issue

ELLIE FOREMAN-PECK FOR NEW STATESMAN
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Craig Oliver, Cameron's attack dog, finally bites

A new book reveals the spiteful after life of Downing Street's unlikely spin doctor.

It must be hard being a spin doctor: always in the shadows but always on-message. The murky control that the role requires might explain why David Cameron’s former director of communications Craig Oliver has rushed out his political memoirs so soon after his boss left Downing Street. Now that he has been freed from the shackles of power, Oliver has chosen to expose the bitterness that lingers among those on the losing side in the EU referendum.

The book, which is aptly titled Unleashing Demons, made headlines with its revelation that Cameron felt “badly let down” by Theresa May during the campaign, and that some in the Remain camp regarded the then home secretary as an “enemy agent”. It makes for gripping reading – yet seems uncharacteristically provocative in style for a man who eschewed the sweary spin doctor stereotype, instead advising Cameron to “be Zen” while Tory civil war raged during the Brexit campaign.

It may be not only politicians who find the book a tough read. Oliver’s visceral account of his side’s defeat on 24 June includes a description of how he staggered in a daze down Whitehall until he retched “harder than I have done in my life. Nothing comes up. I retch again – so hard, it feels as if I’ll turn inside out.”

It’s easy to see why losing hit Oliver – who was knighted in Cameron’s resignation honours list – so hard. Arguably, this was the first time the 47-year-old father-of-three had ever failed at anything. The son of a former police chief constable, he grew up in Scotland, went to a state school and studied English at St Andrews University. He then became a broadcast journalist, holding senior posts at the BBC, ITV and Channel 4.

When the former News of the World editor Andy Coulson resigned as No 10’s communications director in January 2011 because of unceasing references in the press to his alleged involvement in the phone-hacking scandal, Oliver was not the obvious replacement. But he was seen as a scandal-free BBC pen-pusher who exuded calm authority, and that won him the job. The Cameron administration, tainted by its association with the Murdoch media empire, needed somebody uncontroversial who could blend into the background.

It wasn’t just Oliver’s relative blandness that recommended him. At the BBC, he had made his name revamping the corporation’s flagship News at Ten by identifying the news angles that would resonate with Middle England. The Conservatives then put this skill to very good use during their 2015 election campaign. His broadcast expertise also qualified him to sharpen up the then prime minister’s image.

Oliver’s own sense of style, however, was widely ridiculed when he showed up for his first week at Downing Street looking every inch the metropolitan media male with a trendy man bag and expensive Beats by Dre headphones, iPad in hand.

His apparent lack of political affiliation caused a stir at Westminster. Political hacks were perplexed by his anti-spin attitude. His style was the antithesis of the attack-dog mode popularised by Alastair Campbell and Damian McBride in the New Labour years. As Robert Peston told the Daily Mail: “Despite working closely with Oliver for three years, I had no clue about his politics or that he was interested in politics.” Five years on, critics still cast aspersions and question his commitment to the Conservative cause.

Oliver survived despite early wobbles. The most sinister of these was the allegation that in 2012 he tried to prevent the Daily Telegraph publishing a story about expenses claimed by the then culture secretary, Maria Miller, using her links to the Leveson inquiry as leverage – an accusation that Downing Street denied. Nevertheless, he became indispensable to Cameron, one of a handful of trusted advisers always at the prime minister’s side.

Newspapers grumbled about Oliver’s preference for broadcast and social media over print. “He’s made it clear he [Oliver] doesn’t give a s*** about us, so I don’t really give a s*** about him,” a veteran correspondent from a national newspaper told Politico.

Yet that approach was why he was hired. There was the occasional gaffe, including the clumsy shot of a stern-looking Cameron, apparently on the phone to President Obama discussing Putin’s incursion into Ukraine, which was widely mocked on Twitter. But overall, reducing Downing Street’s dependence on print media worked: Scotland voted against independence in 2014 and the Tories won a majority in the 2015 general election.

Then came Brexit, a blow to the whole Cameroon inner circle. In his rush to set the record straight and defend Cameron’s legacy – as well as his own – Oliver has finally broken free of the toned-down, straight-guy persona he perfected in power. His memoir is spiteful and melodramatic, like something straight from the mouth of Malcolm Tucker in The Thick of It. Perhaps, with this vengeful encore to his mild political career, the unlikely spin doctor has finally fulfilled his potential. 

This article first appeared in the 29 September 2016 issue of the New Statesman, May’s new Tories