A POST-OP STEAK, HOLD THE SALAD

YOU’D never stumble upon an Alcoholics Anonymous meeting in a bar or a Gamblers Anonymous get-together at the Sands, but a certain group of obese and formerly obese people ventured to the Old Homestead Steakhouse last week to dig into some sirloin, sip some wine — and skip the salad.

These weren’t ordinary fat-fighters, but men and women who have had lap-band surgery at the NYU Langone Medical Center.

That means they’ve had a band put in place to cinch off the top of the stomach, which helps people feel full, not eat as much and — ta-da — lose weight.

For these eaters, overindulging means more than a tighter waistband and a guilty conscience. For them, one bite too much will literally make them sick — enough to scare anyone from going to restaurants, especially in New York, where dining out is such a part of the culture. After the procedure, they have to relearn how to eat.

“People are very nervous about all the food going down,” says George Fielding, a surgeon and co-director of the NYU Program for Surgical Weight Loss. “Will they be sick? Will they be embarrassed?”

Fielding hosts quarterly “Dinners with George,” held at an array of the city’s nicer restaurants to help patients feel normal about eating out.

“A lot of these people have never been to these kind of restaurants,” Fielding says. “You shouldn’t not be eating out because you’re fat.”

And Fielding himself is proof that “normal” can be achieved. He’s not just a lap-band surgeon, he’s also a patient. The Australia native got the band in 1999 and lost 100 pounds.

At the Old Homestead, the group of 30 or so patients as well as the center’s other lap-band surgeons choose between red and white wine, which Fielding encourages to help them relax.

Most of the diners haven’t considered a filet mignon since surgery.

“I haven’t seen a steak knife in a very long time,” says Lizete Visners, a 36-year-old blonde from Astoria wearing a halter maxidress and a tattoo down her back.

Now a size 12, she displays her “before” photos — she lost 130 pounds.

“No one recognizes me,” she says. “I don’t recognize myself.”

Visners had the surgery in October 2007. Within four months, both of her brothers had it, too.

She shows off her official lap-band card, which allows her to take food onto airplanes and order off kids’ menus.

“I love it,” she says. “It’s like my American Express card.”

Before they order, Fielding offers advice: Take small bites, chew, swallow, put down your fork and wait 30 seconds.

“I eat like a size 6 girl,” he tells them. “They take small bites of everything.”

Oh, and skip the salad (vegetables are hard to get down), try the mac and cheese with truffle oil and don’t clean your plate.

“You’re paying for the experience, not the consumption of food,” Fielding says.

That’s no problem with this crew. One woman, Amy Sokal, 32, who lost 100 pounds, is full after four sips of onion soup.

Dinner veteran Robin Young, who went from a size 32 to a size 8 four years ago, eats about four bites of her filet mignon and orders a doggie bag — for her dog.

John Sagaria, 42, who got the lap band seven years ago and has kept 275 pounds off, has his first steak in eight years.

“It’s good, but I’d rather have fish,” he says. “I’d rather eat faster. You have to chew and chew and chew.”

Between chews, it’s not what your mother would call dinner-table conversation: There’s a lot of talk about what foods stay down (i.e., pureéd soups) and what foods don’t (enough said).

Fielding stops by each table to remind diners to eat slowly. “You don’t want to see it twice.”

Everyone laughs.

“Isn’t he amazing?” asks lap-band patient Ralph Affoumado.

Everyone chimes in: “Yes!”

marymhuhn@nypost.com