There's calorie-counting guilt ('I've eaten too much'), nutrient-specific guilt ('I can't believe I ate all those carbs') and top-of-the-food-chain guilt ('Oh that poor abused/murdered chicken').
And then there's cultural guilt.
This is the shame of travelling halfway across the world to some exotic land, only to find yourself hankering for the familiar.
The yearning varies. For some, it's McDonald's fare. For me, it's grub from any Asian restaurant.
Whether it's tom yam or thosai, I feel like I'm wasting an opportunity for a local dining experience or anthropological adventure. Even glancing at a bowl of rice feels like a cop-out.
Lion Heart, Be Still: Everyone flocks to London's Chinatown for things Chinoiserie and good food, but don't succumb to any of the all you-can-eat-for-a-ridiculous-price buffets.
I know I'm not alone. Food-obsessed Singaporeans don't generally do well if you deprive them of Asian food. You with the chilli sauce in your luggage, you know who you are.
After six months in London last year, however, I think I've finally learnt to deal with both the cravings and the cultural angst.
My therapy: an increasingly cosmopolitan dining scene that dishes up some great Asian fare.
This hasn't always been the case. Eating out in Britain has improved greatly in the last decade, as has the quality of the Asian food available.
While enrolled at a university there in the mid-1990s, I remember being horrified at what passed for Chinese, Singaporean, Indonesian, Malaysian and Thai food (though being desperate, I ate it anyway).
Today, even if you travel mainly to eat, I would argue for scheduling a few Asian stops on your tour of London.
One of the first should be Bar Shu, a Sichuan restaurant in Soho.
With more Brits realising that 'Chinese' doesn't have to mean 'Cantonese', other regional cuisines are seeing their stock rise.
In fact, the idea of an upmarket restaurant devoted to non-Cantonese dishes was so novel that, when Bar Shu opened last year, it was like noodles had just been invented.
Critics rushed over and - bless them - ordered the most exotic-looking dishes on the menu. Many of these happened to be the spiciest as well but the pain seemed to produce nothing but glowing reviews.
Thankfully, the place lives up to the hype. Classics such as dry-fried green beans and gongbao chicken share the menu with cold duck rolls with salted egg yolk, and 'fire-exploded kidney flowers'.
But the real baptism of fire is the hotpot.
If you've never tasted proper Sichuan cooking, this is a hell of a way to discover that there are at least three types of hot - chilli hot, piping-hot and tongue-tingling, my-face-is-paralysed hot. And that you can feel them all at once.
For more mainstream, less thermonuclear dining, you can't do better than the Royal China group of restaurants, whose dim sum rivals the best in Hong Kong and Singapore.
It's easy to take good dim sum for granted in this part of the world - you expect your dumplings and bao to pass ISO standards.
So extra credit to Royal China for meeting the mark and occasionally surpassing it.
It does the most luxurious lor mai fan I've ever seen, for example - the glutinous rice studded with fluffy yellow clouds of egg as well as the usual treasures.
Follow your nose: The crispy duck which you can get anywhere in London's Chinatown.
Another aspect of Asian dining worth exploring is one that puzzled me for a long time - a riddle hidden in an enigma wrapped in a pancake.
It's something you only ever get in Britain: crispy aromatic duck.
It looks like Peking duck, tastes like Peking duck and probably quacked like Peking duck at some point, but it isn't quite the same beast.
The trimmings are similar, but whereas in Asia your pancake holds a shiny rectangle of crisp mahogany skin, sometimes with a layer of juicy flesh underneath, this bird is (like several British culinary innovations) deep-fried.
It sounds dodgy but the process actually renders off much more fat, leaving behind a drier, crispier flesh that's quite yummy.
Those who have had both versions actually prefer this one, which you can even buy as an oven-ready meal at Marks & Spencer's. I know of a family who faithfully cart some back to Singapore whenever they visit London.
Practically every other restaurant in Chinatown serves it. Mr Kong's in Lisle Street is said to be among the best.
Going pho-crazy
Chinese food is only a part of the city's gastronomic mosaic though, and the good thing about being an equal-opportunity eater is that you end up trying things you never would at home.
Take Vietnamese food, for instance. It hasn't exactly imprinted itself on Singapore foodies' consciousness, perhaps because we don't have a large Vietnamese community.
But London does - at least enough to sustain a clutch of Vietnamese eateries in Shoreditch.
One of the most popular is Song Que, which does a nice pho, that fragrant rice noodle soup served steaming hot with scads of fresh herbs and beef or chicken.
About 20 permutations of it dominate the menu, but equally good are the dry vermicelli noodles, served with lean pork and a massive, crunchy, chopped-up spring roll.
Other must-haves are the luscious eggy crepes stuffed with chicken, prawns and beansprouts, and the diaphanously delicious rice paper rolls.
Another cuisine Singaporeans aren't that familiar with is Myanmar's. The Brits aren't either - the Mandalay in Edgware Road is London's only Myanmar eatery.
The fritters alone are worth the trip - crunchy little knots of vegetables, chicken and onion with spicy sauces - but the bottle gourd soup, lamb meatball curry and salad of green papaya and cucumber work as excuses, too.
So-hip-it-hurts
At the other end of the scale is an entirely different species of Asia-in-London dining - the 'destination restaurant'.
Named in Restaurant Magazine's list of the top 50 places to eat in the world last year, Nobu is the so-hip-it-hurts dining room known for both its black miso cod and its broom closet (where Boris Becker famously fathered a love child between courses).
I couldn't find the closet but I can vouch for the cod - it's so good you won't want to swallow it.
Worshipping the same cod: Nobu's famed black miso cod doesn't taste that different compared to elsewhere.
However, it must be said that the dish is so simple and has been so widely copied that it didn't taste all that different here compared to anywhere else I've had it.
Other signature offerings may be more memorable: rock shrimp tempura with ponzu and jalapeno sauces; tiradito, a Peruvian-style sashimi; and a chocolate bento box with green tea ice cream.
Now part of an international chain, Nobu has been accused of being snooty and celebrity-infested. But the food's undeniably good. I don't know if it's 12th-best-in-the-world good, but if you don't mind the credit-card workout, then it's worth it.
The same could be said for Hakkasan, which in addition to being No. 36 on that list, is also the only Chinese restaurant on the planet with a Michelin star.
Don't be fooled by the mongrel name - the Hakka stew was the only nod to Khek cooking I could see on the menu.
What you mostly get are dishes such as silver cod laced with champagne and honey, and Peking duck with caviar, all prepared with care and composed with subtlety (except for the radioactive-looking green dumplings).
Still, this is mainstream Chinese cuisine reinterpreted for Western fine-dining tastes - so there's a bit of punch-pulling in terms of the intensity of flavours and spices.
Now, it would be pointless to argue for or against the Asianness or authenticity of any of these places or compare them to their counterparts here.
I'm also not going to pretend that I don't adjust my expectations when I sit down to any meal served far away from its mother continent.
The good thing about moderated expectations, though: You're sometimes pleasantly surprised. And as a bonus, you don't have to travel with your own condiments.
Addresses of eateries
Bar Shu: 28 Frith Street, Soho
Royal China: 68 Queen's Grove, St John's Wood. It has several other branches, including one in Baker Street.
Mr Kong: 21 Lisle Street, Chinatown
Song Que: 134 Kingsland Road, Shoreditch
Mandalay: 444 Edgware Road
Nobu: The Metropolitan, 19 Old Park Lane, Mayfair
Hakkasan: 8 Hanway Place, off Tottenham Court Road
5 things to do
1 Do spend a day gazing and grazing at the fabulous Borough Market, whose stalls flog a headspinning array of cakes, pies, cheeses, breads, jams and sweets, as well as fresh fruit and vegetables, meats and seafood. Stop at the Monmouth Coffee Company for cappuccinos, at Brindisa for tapas, or at Roast for a traditional British supper.
Open Thursdays through Saturdays.
See www.boroughmarket.org.uk for times.
Slides at the Tate Modern
2 Do scream when you zip down the slides at the Tate Modern. As with previous installations displayed in the massive Turbine Hall, no one's quite sure if Carsten Holler's creation qualifies as art, but it's so much fun you won't really care. And it might be your only chance to get away with this sort of behaviour at a world-class art museum.
It's free and on till April 15. See www.tate.org.uk/modern for details.
3 Do jump on a river boat to Greenwich. Even if you've lived in London or visited dozens of times, the superb views on this hour-long trip on the Thames will give you a totally different perspective on the city. The boatman will grab a microphone and gab away about everything from the architecture of Christopher Wren to how much Cher paid for her river-view flat. Boats leave regularly from Embankment or Westminster piers.
When you get off in Greenwich, you can end your day with a leg in each hemisphere at the famous observatory and Prime Meridian. See www.tfl.gov.uk for boat times.
4 Do check out the different neighbourhoods of multi-cultural London. Head south of the river to Brixton for a slice of Afro-Caribbean life, including the famous Electric Avenue Market and arcades; or to the capital's 'Little Portugal' in South Lambeth Road (between Vauxhall and Stockwell tube stations) for authentic Portuguese patisseries, bars and restaurants.
5 Do stop for afternoon tea. It's touristy and a bit of a cliche but there's something about fine china and obsessively cut cucumber sandwiches that's so deliciously camp.
If you want the full monty, there's the legendary tea at The Ritz in Piccadilly. For something more low-key, try the Cadogan Hotel in Chelsea.
2 don'ts
1 Don't succumb to any of the all-you-can-eat-for-a-ridiculous-price buffets you see in touristy areas such as Oxford Street and Chinatown. It's theoretically possible to get a decent meal this way, but if you spy crowd-control issues developing near a row of metal chafing dishes, walk away.
2 Don't try to buy a durian in this country. They tend not to have survived the journey well.
