Epistemological Indulgences

December 22nd, 2007 by Ben Goldacre in adverts, bad science, chocolate, nutritionists | 14 Comments »

Ben Goldacre
The Guardian,
Saturday December 22 2007

Christmas is a time for harmless lies, the chocolatey indulgences of the thought world. We know when to stop, because if we all acted on our belief in Santa there would be no presents: and then Christmas would be meaningless.

My favourite Christmas traditions are the “red wine is good for you” and “chocolate is good for you” stories, which have become a festive science tradition of their own. Red Heart Wine, from Sainsbury’s, with extra antioxidants, is “a red wine that is actually good for your heart”.

Drink it down with new Choxi+, milk chocolate with “extra antioxidants”. “Guilt free,” says the Daily Mail, it’s “the chocolate bar that’s ‘healthier’ than 5lbs of apples”. “Too good to be true,” says the Mirror. “Chocolate that is good for you, as well as seductive,” says the Telegraph. The Choxi+ manufacturers recommend two pieces of their chocolate every day. It’s almost as good as Fruitella Plus, with added vitamins A, C, E and calcium.

These are jokes which have gone too far, fat and spotty on wishful thinking. Antioxidants are like an endlessly repeated Christmas movie that you’ve never quite watched from start to finish: let’s recap.

Firstly there’s the theoretical plausibility, from biochemistry textbooks. Sainsbury’s tells this story in the style of a children’s story. “Exposure to UV rays, pollution and smoking produce free radicals,” they say. Oh modern woes! “Free radicals are compounds that cause cell damage, which in the long term can damage health.” It’s a simple tale of right and wrong. “Antioxidants help counteract the harmful effects of free radicals.”

It’s an attractive idea. But if you’re going to pore over the flowcharts in a biochemistry textbook, and pick molecules out at random on the basis of their function in the body, then you can prove anything you like. When you have a bacterial infection white cells build a wall around invading bacteria and then use free radicals – amongst other things – to kill them off, like tipping bleach down the toilet. Should we be selling wine with extra free radicals, instead, to help people fight bacterial infections, on the grounds of theoretical plausibility?

Anyway. In the 1970s men who looked like Father Christmas made amazing discoveries about smoking and health: buoyed with the enthusiasm of it all, they decided that all other cancers must have lifestyle causes, such as diet perhaps. They started looking for data, and this is what they found: people who choose to eat antioxidant pills seem to live longer; people who choose to eat fruit and vegetables seem to live longer; fruits and vegetables contain lots of antioxidants.

Are antioxidants the key to that link? Possibly. But people who choose to eat fruit and vegetables are getting a lot of good stuff into them, and they’re also like me: they’re a bit posh, they get plenty of exercise, they work, they have strong social supports, and more.

So trials were done, in huge numbers, giving one group extra antioxidants, in pills, and the other group our old friend the placebo sugar pill. Some of these trials were stopped early because the people getting the antioxidants were dying faster. Overall, if you look at all the results on a big spreadsheet (a technique called meta-analysis) it seems that antioxidant supplement pills either do nothing, or worse, kill you quicker. There might be something in the antioxidant story, but they might be rubbish. You don’t read that everyday in press releases on wine and chocolate.

So what does this do for our Christmas fable? Well fruit and veg are definitely still good for you. But you like chocolate. I’m not your mother. Eat it. Enjoy it. Believe in Santa. Chocolate is healthier than 5lbs of apples. And in the new year you can perform a symbolic purification ritual, involving five days of abstinence. You can dress that up in crap science too.

· Please send your bad science to bad.science@guardian.co.uk

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14 Responses

  1. Maarten Van Hemelen said,

    December 22, 2007 at 7:07 pm

    I never quite got why people are so obsessed with this. If you like to eat chocolate, it probably won’t kill you if you don’t overindulge. Isn’t the most important thing that you get variation into your menu?

  2. tregenza said,

    December 23, 2007 at 12:35 pm

    Maarten said: “Isn’t the most important thing that you get variation into your menu?”

    Definitely – so make sure you eat a good balance of milk, white and dark chocolate.

  3. Ambrielle said,

    December 23, 2007 at 2:38 pm

    Don’t forget chocolate-covered raisins and nuts for that extra protein and vitamins.

  4. thekumquat said,

    December 23, 2007 at 7:13 pm

    When I was little I had a Ladybird cookbook, which informed me that it was important to eat lots of chocolate as chocolate was ‘high in iron, which is needed for healthy blood’.

    Sadly my mum disagreed and told me not to believe everything I read in books. Which was probably a useful lesson in the long run…

  5. Twm said,

    December 24, 2007 at 2:20 am

    Vitamin C jus short fo Vitamin Chocolate?

    Apparently lots of dogs are taken to vets this time of the year due to acute chocolate poisoing because they cannot metabolise the theobromine quick enough.


    When it comes to pooches, death by chocolate is a real concern.

    One of the problems with reading about free radicals is that they are presented as devastating chain reaction with no end – unless you take the intitative and start actively consuming antioxidents(with a pill being a good way to catch up).
    It does sound scary.

    Free radicals are implicated in the aging process also.

    I’ve heard many descriptions of freeradical exposure as “like your body rusting”.
    By following a restricted calorie diet, you might live longer. But that would rule out chocolate anyway.

    Personally i would rather die at a “normal age” than have to give up kit kats and ostrich egg scotch eggs.

  6. BSM said,

    December 24, 2007 at 11:40 am

    For the real toxic double-whammy try chocolate raisins for dogs.


    The quantities required for chocolate toxicity are not huge, but you’d probably know the dog had had some and early intervention usually helps.

    By the way, I just reminded myself of the figures from the Veterinary Poisons Information Centre:

    Milk Chocoloate 9g/kg
    Dark Chocolate 1.2g/kg
    White Chocolate 2.2kg/kg. (Yes that is more than twice their bodyweight in white chocolate and I think even a labrador would struggle with that.)

    So only 1oz of dark chocolate can poison a labrador and I’d always recommend seeking advice for any significant ingestion.

    My own pup ate a load of chocolate coins last Christmas. She weighed 4.2kg at the time and I spent a festive afternoon emptying her stomach.

    The danger of raisins and grapes is that it may be an idiosyncratic reaction where some animals are fatally affected by an apparently trivial dose. So a couple of grapes may not harm some dogs but kill others.

    And on that cheerful note,

    Merry Christmas

    Badly Shaved Monkey MRCVS

  7. AitchJay said,

    December 25, 2007 at 6:48 am

    Nice article Ben, punchier than your usual, I like it..

    Merry Xmas all!

  8. Observer said,

    December 26, 2007 at 12:30 am

    Ben wrote: ‘My favourite Christmas traditions are the “red wine is good for you” and “chocolate is good for you” stories’ Do you get the good effects of both with brandy filled chocolates?

  9. Maarten Van Hemelen said,

    December 27, 2007 at 3:43 pm

    Isn’t red wine good for you? I mean, in moderate quantities like one or two glasses a day, not like drinking two bottles in one hour.

  10. emilypk said,

    December 27, 2007 at 7:56 pm

    p.s. on the ‘is you housing killing you’ link in the mini blog–I especially liked: “…and a PhD investigating indoor air in homes.”

    That must be a very clever PhD indeed!

  11. Ben Goldacre said,

    December 27, 2007 at 8:13 pm

    heh i’m going to sort out enabling comments on the miniblog soon.

  12. andyl said,

    December 30, 2007 at 2:59 pm

    How many chocolate raisins do I have to eat for them to count as one of my five portions of fruit and veg a day?

  13. Jari said,

    March 11, 2008 at 7:42 am

    Maarten, not just red wine but alcohol itself can be good for you. (See ‘Drink And Be Healthy’ at www.roughgang.com.) However, there are obviously other things to consider such as the bad unscientific driving you might be doing afterwards.

  14. JHvW said,

    April 21, 2011 at 1:28 pm

    We have an old family anecdote. A man goes to his GP and asks: If I stop drinking, stop smoking and abstain from sex, will I live to be a hundred?

    The doctor shook his head and said: “I don’t think so, but it will seem like it!”