It was 1987 when I started drinking Diet Coke. It only dawns on me now how fashion forward this was, considering it had been invented just five years before (the other drink I took to this same year, beer, had been discovered in early Neolithic times). Although it would be an exaggeration to say that everyone at my school was anorexic, I do remember someone trying to find out how many calories were in human flesh, because she'd just absent-mindedly chewed some skin off her thumb (this was before Google). To drink Fat Coke in an atmosphere like that would have been a gesture of defiance. Which was fine, people made those, even in the 80s, but you had to be really thin. Otherwise you just looked as though you had no control.
Diet Coke celebrates its 30th birthday this year, as the second most popular soda in the world, after Coke. This placement happened in 2010, and was a cataclysmic fizzy-pop event, a diet drink outstripping a full-fat drink – Pepsi, formerly the second most popular. Finally, at 28 years old, Diet Coke's wish had come true – people were drinking it just for the taste. Sales in Britain have gone up 6% in the past five years; 40% of colas sold are either Diet Coke or Coke Zero.
Like anything else whose only imaginable ingredient is carbonated water (can you picture aspartame? Acesulfame K?), it comes in for a certain amount of mistrust, ranging from real health anxieties (we'll get to those) to a sniffy, "if they don't sell it in Monmouth Coffee Company, I'm not drinking it" disapproval. It will never meet that test of the wholesome foodstuff (would your grandmother know what it was?) and it will never be rehabilitated by a Nigella recipe (unlike Coke and even Cherry Coke, which can both be used to bake ham). There has always been a slight shame attached to it, since – with the caffeine, and that sheer unknowable lift – it bespoke an addiction that couldn't be hidden behind a connoisseurship, unlike alcohol or coffee. You'll never be a connoisseur about something that's mass produced and always tastes the same. (In fact, this isn't true of Diet Coke – there's a different recipe for some parts of the Mediterranean market, and it isn't as nice. Still, "nice" and "not as nice" – there is not enough stratification here.) In the 80s, it was too new to be cool. So it was very uncool not to drink it, but it wasn't totally cool to drink it either.
Diet Coke had another stroke of genius in the middle of the decade. Its first stroke of genius was changing its name from Tab, which had been the name of the Coke diet-variant since the 60s. They hadn't wanted to use "diet" in the title originally, since they didn't want the drink to be associated with self-denial. In fact, you can associate a diet drink with almost any negative idea or trait (look at Diet Tango's sell line – "you need it because you're weak") and people will still drink it, because it's fizzy. But nobody knew that to begin with. The other problem with the "diet" concept is that it locks the drink pretty firmly to one gender, which is a needless waste – in terms of marketing opportunities – of the other gender. This started out true and remained so for years – Coke Zero was introduced as late as 2005 to appeal to the men who liked the taste and idea of zero calories, but didn't want to look like those kinds of men (women). Coke Zero seemed like a failure because nobody stopped consuming Diet Coke to drink it; in fact, it took off; the public embraced it as a totally separate drink. If they'd written that on a strategy document – we're going to make the same drink, with very slightly different ratios of wholly artificial taste-simulators, give it a nakedly manipulative name and hope to sell it without denting the sales of its diet prototype - I like to think they'd have been laughed out of a job.
Anyway, it wasn't an entirely necessary invention because a decade before Diet Coke had had its second stroke of genius which made the drink such a universal that it became unisex. In 1983 it bought Columbia Pictures, pioneering the idea of product placement, which led to the Coke-chasm, where the nation at large drank more and more regular Coke, and the inhabitants of Hollywood, like an aneurysm in America's bloodstream, drank more and more Diet Coke, to the point where, in 1988, it was almost the drink of choice at the Governor's Ball following the Oscars (it was eschewed in the end, in favour of booze. You can embrace aspartame as throatily as you wish, but you cannot pretend it makes you drunk). The upshot of this is that America as a whole has become larger and larger, while its stars have become smaller and smaller, to the point that if you put Teri Hatcher next to a regular person, you'd have to assume she belonged to a different species.
That was just a flight of fancy. Teri Hatcher would never stand next to a normal person for fear of catching normality. And there is no evidence that Diet Coke actually makes you thin, though attempts by the media to prove that it makes you fat have come to nothing. There have been studies showing that people who drink a lot of diet soda generally (not Diet Coke in particular) have larger waist circumferences, but none prove cause and effect. However, as amusing as it is to think of the discovery – maybe it will arrive in time for the half centenary – that Diet Coke makes you fat, there are other health scares which, if true, would be much more troubling.
Aspartame, like every other chemical or activity that is peculiar to modern life, has been thoroughly investigated as a possible cause of cancer, diabetes, heart disease, fertility problems; at the moment there's just nothing in it. But in the world where products are tested, and there are agencies of food standards, and there are rules about who can sell what to whom, on the grounds of health the only serious recommendation ever made was that you shouldn't drink more than 18 cans of aspartame-containing drink a day. I was drinking a Diet Coke when I met Carole Caplin once, and she said, "It's osteoporosis in a can, you know". But she wasn't talking about diet drinks, she was talking about any carbonated drink – the bubbles irritate your stomach, your stomach responds by producing alkaline, which most likely it will get from the calcium in your bones. I know someone who gave himself osteoporosis by eating nothing for three years but baked beans poured over pasta. I'm just saying, there are a lot of ways to give yourself a bone disease, and they are not all as enjoyable as Diet Coke.
In the absence of any damning evidence, Diet Coke now occupies that twilight zone – along with dairy, wheat and Snack-a-Jacks. There's nothing actively wrong with them, but if you feel your body is a temple, you won't let them in it. Understanding this, in 2007, DC (that's what they call it in America) launched Diet Coke Plus. It was all the fun of the chemicals, with added nutrients. Nutritionists didn't get it – why would you need vitamins in your drink? Why couldn't you just take vitamins with your drink? If everybody thought like that, they'd never have invented the cocktail. Perhaps unsurprisingly, Diet Plus went nowhere. People didn't want vitamins in their drink, because the last thing you want to be reminded of while you're drinking artificial sweetener is the health-giving bounty of the natural world. If I had to accompany Diet Coke with anything, I'd want it to be freeze dried space food. Personally, I favour the drink when I have drunk so much coffee that it feels morally wrong to drink any more. Since Diet Coke has caffeine in it as well, this is an irrational measure, but no less irrational than the people who drink it when they want some sugar but don't want the calories, and then go ahead and have a bar of chocolate as well.
The appeal of the drink in public life is, I believe, for the sorts of people who aren't allowed to have a visible vice to show that they have the devil in them somewhere. Bill Clinton famously loved Diet Coke (in fairness to him, he had no need to manifest his saturnine desires with a soft drink. So he just probably likes the taste). Barack Obama loves it (I like to think it's something he wishes he didn't drink. You can't imagine in his best self, when he and Michelle get together to work out their weight targets for the year, pledging to drink more Diet Coke). Furthermore, in the UK at least, it is the mark of the metrosexual (for men) and the mark of the slut (for women – I mean slut in the older sense, of being a bit ramshackle around the house). I'm not making any statement about the economy or about Iraq, OK, but I cannot imagine Gordon Brown knowing one end of a Diet Coke from another, whereas I can imagine Tony Blair (and Alastair Campbell) drinking it quite a lot, Carole Caplin's reservations notwithstanding. Since you ask, David Cameron drinks Beefeater triples and Nick Clegg drinks Schloer. Still in my imagination.
In real life, accidental endorsements and the atmospheric support of Hollywood have always served Diet Coke better than its chosen celebrities, whom it gets wrong (Paula Abdul). This doesn't mean they've never had a good advert: I'm thinking specifically (only) of Diet Coke break, in which a number of women gather round to watch a male construction worker, who always removes his shirt at 11.30am, the better to enjoy his Diet Coke. The women aren't drinking, they're just looking; there are a few of them, so it's much more like the appropriation of a male sexual fantasy (group ogling, a kind of fellowship in desire) than it is a classic female one (which tends to be one woman fixed on one man). It's meant to be witty (reversal of expectation), and modern (sisters are doing it for themselves), but it had the apparently unintended consequence of making men think: "Huh. There's a man drinking a woman's drink, and it looks like he's really enjoying it!"
Plenty of people never came round to the taste of it, and they would see it as one of the punishments of self-improvement, along with sugar-free jelly and cottage cheese. They will see its 30th birthday as a mystery of marketing, a baffling triumph of habit and gullibility over sense, health, reputation, gender-expectation (in some cases) and taste. Everybody else will understand how it came of age – it's because it's delicious.
'Diet drinks have no nutritional value': the nutritionist's view
Diet drinks are very processed substances and can contain a high amount of caffeine, which works as a diuretic on the body, leading to significant losses of water. This causes dehydration, while various nutrients – including calcium, magnesium, and vitamins B and C – can be lost through urine. My second concern relates to the phosphoric acid preservative in them, which creates phosphates in the body. These can reduce the absorption of calcium in the gut, and can trigger the parathyroid gland to cause the release of calcium from bones, both of which can contribute to poor bone density. Diet drinks have no nutritional value.
Artificial sweeteners are a very controversial subject. Some governmental health authorities may say they are safe enough, but in the nutrition industry, that's still up for debate. Some studies indicate that the man-made molecular structure of some artificial sweeteners could be linked to certain health problems. This requires much more research. Research however, has indicated other adverse issues from consumption of artificial sweeteners, including encouraging sugar cravings; and increasing appetite. Replacing sugary drinks with diet drinks doesn't help to reduce weight by itself. In fact, some epidemiologic data suggests a positive correlation between artificial sweetener usage and weight gain. Recent research suggests that water promotes weight loss better than diet drinks, as well as improving blood pressure and hydration levels.
Anne-France Rix is a nutritional therapist (www.TheFoodDoctor.com). She was talking to Patrick Kingsley
