Every year, hundreds of thousands of Americans turn to stomach-shrinking bariatric procedures , hoping for extreme weight loss.

All of these reduced appetites might seem like bad news for the restaurant business, but surgeon-distributed food discount cards aim to make dining out cheaper and more practical for gastric bypass patients.

But is this kind of encouragement really a good idea?

To accommodate the patients' reduced stomach volumes, the cards, called WLS (Weight Loss Surgery) cards , ask restaurants to allow patients to order a smaller portion of food for a discounted price.

These cards aren't a new phenomenon — they've been around in the U.S. at least since the 1990s, and a similar discount program was proposed to city council members in Campinas, Brazil, earlier this year.

And like the surgery itself, the WLS cards have grown in popularity, says Ann Rogers , director at the Penn State Surgical Weight Loss Program. "Now there's so much word of mouth about it, that if we forget to give them out [after surgery], the patient says, 'What about those discount cards?' " Rogers says.

Some popular U.S. restaurants accept the cards. For example, Cracker Barrel restaurants allow patients to order from the inexpensive children's menu or order a lunch-sized portion for dinner. In a statement issued to the Salt, Olive Garden and Red Lobster restaurants say they are happy to do the same.

Even "all-you-can-eat" buffet restaurant Golden Corral provides a discounted buffet price upon seeing a proof-of-surgery card in some locations.

Though gastric bypass surgery leaves the patient with a stomach pouch only about the size of an egg, restaurants, especially buffets, still spell trouble for many patients. Unlimited portions and heavily processed, quickly digestible foods that keep patients from feeling full make it difficult to keep the weight off, says Rogers.

Golden Corral could not provide a spokesperson to respond to our inquiries, but it and other companies have made efforts in recent years to add healthier choices to their buffet offerings.

Even if the patient makes better choices, however, friends and family who come along may not do the same. "I definitely discourage patients from going to buffet-style restaurants — it's a danger for everybody," Rogers says.

In fact, Rogers says she discourages her patients from eating at any restaurant. So why distribute a discount card that seems to encourage dining out?

Rogers says it's OK for patients to use the WLS card and splurge at the buffet every once in a while, and the card also encourages them to order smaller meals at other restaurants. If patients make healthy choices about 75 percent of the time, they'll keep the weight off, she says.

But just as the buffet can have negative family health consequences, patients who are diligent about eating well a majority of the time can encourage healthy habits among friends and family. Rogers says patients who attend regular follow-up appointments, some featuring weigh-ins and healthy cooking classes, retain their lost weight about 70 percent of the time.

"For most of our patients, when the patients change their habits, it changes the eating habits of the whole household. It's pretty educational," she says.

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