Another new year and another host of celebrity dieters, but it's not a modern phenomenon. Lord Byron was one of first diet icons and helped kick off the public's obsession with how celebrities lose weight, says historian Louise Foxcroft.
There has never been any shortage of celebrities who have followed diets, endorsed them or tried to sell us one of their own devising, even back as far as the 1800s.
The "mad, bad, and dangerous to know" Lord Byron was thought of as the embodiment of the ethereal poet, but he actually had a "morbid propensity to fatten". Like today's celebrities, he worked hard to maintain his figure.
At Cambridge University, his horror of being fat led to a shockingly strict diet, partly to get thin and partly to keep his mind sharp. Existing on biscuits and soda water or potatoes drenched in vinegar, he wore woolly layers to sweat off the pounds and measured himself obsessively. Then he binged on huge meals, finishing off with a necessarily large dose of magnesia.
In 1806 Byron weighed 13st 12lbs (88kg), but he was under 9st by 1811 (57kg) - a huge weight loss of nearly 5st (32kg). We know all this from records at Berry Bros & Rudd, a wine merchants of St James's, London.
Here, stylish men-about-town weighed themselves on hanging scales, as personal bathroom scales were an early 20th Century phenomenon. The Regency dandy, Beau Brummell, weighed himself there over 40 times between 1815 and 1822. He went down from 12st 10lbs (81kg) to 10st 13lbs (69kg).
At the infamous Villa Diodati on Lake Geneva, in 1816, Byron was living on just a thin slice of bread and a cup of tea for breakfast and a light vegetable dinner with a bottle or two of seltzer water tinged with Vin de Grave. In the evening he stretched to a cup of green tea, but certainly took no milk or sugar.
To suppress the inevitable hunger pangs, he smoked cigars. By 1822, he had starved himself into a very poor state of health, even though he knew that obsessive dieting was "the cause of more than half our maladies".
Because of Byron's huge cultural influence, there was a great deal of worry about the effect his dieting was having on the youth of the day. Dr George Beard attacked the popular Victorian association between scanty eating and delicacy of mind because impressionable Romantics were restricting themselves to vinegar and rice to get the fashionably thin and pale look.
"Our young ladies," he wrote, "live all their growing girlhood in semi-starvation." This was for fear of "incurring the horror of disciples of Lord Byron", he added. It didn't help that Byron himself had suggested that "a woman should never be seen eating or drinking, unless it be lobster salad and champagne, the only truly feminine and becoming viands".
But his cruel double standards were exposed when, on ending his scandalous affair with the married Lady Caroline Lamb, who had become gaunt with grief, he quipped that he was "haunted by a skeleton".
Another excessively slim 19th Century celebrity was the beautiful and narcissistic Elisabeth von Wittelsbach - known as Sissi. She was empress consort of the Emperor of Austria, Franz Joseph I.
She developed an extraordinarily strict diet and exercise regime to help her cope with an intensely critical public gaze, evoking parallels with Princess Diana. Newspapers in the 1860s pored over her life and printed exaggerated stories about her.
Taller than her husband by several centimetres, she weighed a mere 7st 7lbs (48kg) and her waist, checked daily by her hairdresser, had to measure 19.5in (49.5cm) or she would not eat.
She exercised vigorously, resembling an outlandish bird as she hung from gymnastic rings in a black ostrich feather-trimmed gown. She also swallowed only emetics, laxatives, oranges, and thin broth or one glass of milk from her own personal cow.
Everyone was getting in on the diet act during the 19th Century, either slimming down or fattening up on the profits of their diets, apparatus, potions and powders. Even Nietzsche and Henry James dieted. Nietzsche tried a traditional restricted calorie diet and James went in for Fletcherism, an elaborate system of chewing each morsel of food several hundred times.
In the 1920s, Hollywood mass dieting really took off. Gayelord Hauser, an LA diet guru and Greta Garbo's lover, exploited the power of the movies. He released that "most of our high-priced movie stars are living in constant fear of losing their attractiveness and thereby their popularity... they simply can't afford to become fat and unattractive".
No diet was too expensive or drastic for them, or for the movie-going public who desperately wanted to be like them. The same can be said today with the global industry worth billions.
The downside of looking up to someone is being looked down upon. The distorted, even obsessive, thinking that characterises our relationship with celebrity can, it is said, be traced to the limbic system of our brains.
Food, sex and memory are all bedfellows in this, one of the oldest, most deeply buried structures in the cerebrum. It is not hard to see how these three fundamental elements become meshed in our perceptions of the celebrity bodies constantly on parade before us. The glimpse of a fat thigh or a double chin before it is air-brushed away can, after all, mean mass denunciation for those trying to elbow their way into the limelight.
There is always a new diet book in the best-seller lists nowadays. Most of them are recycled, re-hashes of previous fads, each one endorsed by a shiny celebrity or two whose "ideal" bodies betray hours of work and a lot of cash investment.
It is the same old line that we have always been sold - we too could be thinner, younger, more loved, if we would only buy whatever new, improved diet food or regime is on offer. And we still fall for it.
Louise Foxcroft is the author of Calories & Corsets