Readers reply: Why is sugar-free tonic water always described as ‘slimline’?

The long-running series in which readers answer other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific and philosophical concepts

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Why is sugar-free tonic water always described as “slimline” (at least in the UK)? As far as I know, every other sugar-free drink takes the label “diet”. I presume the reason is historical – and possibly colonial – but I welcome the readers’ thoughts. Amanda, Dundee

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Schhh … you know who decided that … geoffhoppy

Yes, Geoff, I remember it well. It was William “Benjamin” Franklyn who, while drinking gin and tonic and conducting electrical experiments involving thunderstorms, discovered that it was better to be on the thin side, thus having better chances of avoiding lightning strikes. As he’d removed the sugar from the tonic water to keep his weight down, while he was guzzling gin for a bit of dutch courage, he noticed he’d drawn a very thin line under his calculations. Geoff is quite right that he decided to keep quiet about the product name and duly became a silent partner in a soft drinks company. bricklayersoption

Mostly because Schweppes slimline tonic came before widespread “diet” soft drinks. Schweppes had been making carbonated mineral waters since 1783. By the 1940s, it was marketing its branded tonic water as a small bottle of mixer for gin (or vodka) sold in bars (with a higher profit margin than generic tonic). The slogan “Schhh … you know who” pushed brand recognition, but also targeted female drinkers more than the company’s previous Royal Navy imagery. In 1965, it introduced the slimline version, recognising there was a market for a low-calorie mixer.

Patio Diet Cola had been test-marketed in the US in 1963 and was rebranded Diet Pepsi in 1964, shortly before Schweppes slimline tonic appeared. Diet Coke was not adopted by Coca-Cola until much later, in 1982. Most of the supermarket own-brand tonics appear to use a simple “low calorie” label, probably to avoid any accusations of passing off. leadballoon

Coca-Cola found Diet Coke sold mostly to women, while men recoiled at the idea of dieting (hard to say whether the ads showing office women gawping at a hunky workman drinking it helped or hindered this). They realised they needed to find a “bloke Coke” that would appeal to men, too. The result was Coca-Cola Zero Sugar, or Coke Zero, which is horrible stuff, but seems to be nudging Diet Coke off supermarket shelves. jno50

Oh no, I prefer Zero over Diet Coke – it tastes more like Pepsi Max and less artificial to this male’s palate. EmpathyIsStrength

Because if you’re selling something so wholly unpleasant, you’re calling in the marketers and they’re justifying their wages by giving it a name other than “extra bitter carbonic acid that’s less drinkable or fun than neat gin”. That’s my opinion anyway, and the world will be a far better place when it starts accepting my ill-tempered and barely considered opinion on any subject as unquestionable fact. BuffPrimer

My guess is that calling it “diet” would sound a bit odd in the context. Most drinks involving tonic water are more likely to be associated with good times than healthy living. “Slimline” sounds more sophisticated and fun. Alex42

The real question is why is anything called “diet” or “slimline”? Presumably it’s to make gullible people think they’ll lose weight if they imbibe such drinks. And it makes you sound virtuous when you order it. Goldgreen

I’m guessing it’s because it was created before dieting was a big thing, though it wasn’t suggested when this very question was asked on Reddit six years ago, so I could be wrong. LorLala

“Diet” seems to be a 1980s US term that’s taken off in the UK. In most of the rest of Europe, sugar-free drinks are labelled “light” or “zero”. I’d guess “slimline” is just an older UK term coined by Schweppes to cash in on the popularity of slimming when it had cornered the market in tonic water. (Fever Tree’s low-cal version is “light”.) alexito

Yes, it was all about slimming in the 70s – little books telling you how many calories in everything, Limmits biscuits and chocolate bars to replace meals, even little toffees [Ayds] you ate before meals to make you less hungry. Ah, the good old days! henrythehorse