In the 1991 rom-com L.A. Story, a waiter circles a group of diners taking coffee orders. "I'll have a decaf coffee," shoots the first. "I'll have a decaf espresso," chirrups the next, followed by orders for "a double decaf cappuccino" and "decaffeinated coffee ice cream", which are trumped by the Steve Martin character requesting "a half double decaffeinated half-caf, with a twist of lemon", triggering universal cries for twists of lemon.
While lampooning the faddish nature of Angelenos, the scene is likely to resonate with restaurants. Speak with any restaurateur or chef worth their salt and they'll tell you how they deal daily – and nightly – with a seemingly ever-rising tide of dietary requirements from diners.
"The world's gone mad with dietary restrictions; everyone's got a problem," bemoans leading Sydney chef Martin Benn. "Sometimes you feel like you're working at a hospital, not a restaurant."
As frustrated as Benn is, he equally recognises food allergies, intolerances and diseases – on the march through greater awareness, better diagnostic testing and environmental factors – are now simply a normal part of running a restaurant.
Waiters often ask diners about their dietary requirements even as they hand them a menu, particularly at top-end establishments.
If you want to appreciate the impact of dietary needs, look at Sydney's Quay. The harbourside fine diner has eight versions of its degustation menu on hand to accommodate guests, ticking off common intolerances such as lactose and gluten (which caters to coeliac disease sufferers) and allergies to nuts and shellfish (there's also a kosher version that rules it and pork out) as well as special diets for vegans and vegetarians, which have been about so long they're almost ho-hum.
For example, Quay's pig jowl with scallop and Jerusalem artichoke (pictured) can be modified for people who don't eat seafood, dairy or pork: spinach replaces scallop; oil replaces butter and eggplant replaces pork.
"We try and anticipate most possibilities, but every now and then you get a few freaky ones," says Quay supremo Peter Gilmore.
He points to his mud crab congee. For those who can't stomach shellfish, he substitutes the crab with palm hearts and white asparagus. The dairy-free version loses the egg yolk-butter emulsion top. For the non-meat eaters, vegetable stock replaces chicken.
He's also added a stock without garlic and onion for those with irritable bowel syndrome, of whom 40 per cent have fructose malabsorption, a recent phenomenon ruling out a long and varied list of foodstuffs, including wheat and lactose but also many fruits and vegetables.
"It means a table of eight can all enjoy a similar dish," says Gilmore, whose approach is more the norm among top-enders than the exception.
Melbourne's Andrew McConnell (Cutler & Co, Cumulus, Supernormal) stresses the importance of delivering customers the same dining experience. "Guests shouldn't be penalised," he says. "You can't always substitute an item . . . often you have to make something from scratch, using a component from one dish or elements on the menu, to compose a dish that's balanced and successful."
Mick Formosa, who occasionally waits at Windsor's Saigon Sally, says that communicating with the kitchen is crucial: "We ask if it's a dislike or allergy, then gauge the allergy level."
But chefs all advise 24 hours' notice results in, as McConnell says, "a better experience".
For many, following a dietary regime is a lifestyle choice. Steve Hodges, the co-owner of Fish Face in Double Bay, has himself reduced his bread intake and only uses rice flour for the batter. "I feel 100 per cent better," says Hodges, who also handles his fair share of shellfish avoiders. "I don't think people are being trendy . . . there are health benefits."
Anthony Musarra, general manager of the Van Haandel Group (Stokehouse, Melbourne and Brisbane) agrees. "People prefer lighter, simpler dishes . . . to eat more healthily," explains the one-time Sydney chef. "It comes down to restaurateurs being intuitive to what society wants and providing it."
It's what motivated Ross Lusted, of Sydney's two-hatted The Bridge Room, to recalibrate his dishes (reducing protein, upping veg), avoid flour (save a dessert or two), serve gluten-free crackers with cheese and prepare his signature chicken with a garlic-free option.
"I have a regular customer with major dietary issues . . . six oysters, plain grilled duck, no sauces," says Lusted, whose wife was raised a vegetarian and father is a coeliac.
Then there are the less-allergy/intolerance-based diets, often endorsed by celebrity, to which restaurants cater. Marque's Mark Best has served a regular couple, adhering to the Japanese spiritualism of Reiki, more than 300 specially created dishes (no onion, chocolate, caffeine, etc).
At Chiara and Bar Nacional, in Melbourne's Docklands, the menus are adaptable for followers of the paleo diet, emphasising consumption of unprocessed foods like our cave-brothers and sisters – but then one of the partners is paleo pin-up Pete Evans.
Even so, chefs remain suspicious some diners are being faddish or fussy. Gilmore had a dairy-free eater still wanting his chocolate cake. Sugarcane's Milan Strbac had a coriander-averse diner OK with the root but not the leaf. "I think a lot of it's made up, to be honest," he says.
Dietitian-cum-hotelier Karen Inge is establishing the Culinary Nutrition Lab, designing apps and resources, to help chefs, particularly in the "grey area" of intolerances.
"What chefs don't understand is [sufferers] can tolerate some amount," she explains. "It's not up to the chef . . . it's up to the individual."