While restaurants are trying to tempt healthy diners, new research suggests that even customers on diets may not care too much about eating healthy when they're dining out.

A new Mintel study reveals that while 55 percent of people surveyed said they have tried to lose weight in the past year, eating healthy isn’t top-of-mind when at restaurants, a third of respondents said.

It’s even worse during parties and other special occasions. Only 8 percent of customers say they look for something healthy when eating out for a special occasion, while 43 percent say they look for something indulgent. The average dinner out is a bit better, with around one in four people saying they look for something healthy when ordering an "everyday" meal.

Mintel's data comes from two online surveys from April 2014 that queried British respondents who have eaten out or had takeaway from a restaurant in the last three months.

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Restaurants are investing serious development and marketing dollars toward "health-conscious" menu items, from Taco Bell's high-protein "Power Platform" to Chick-fil-A's updated grilled chicken recipe. However, healthy food apparently isn't what ends up on customers' plates.

The recent failure of Burger King’s “Satisfries” is a one example of what happens when a chain gives supposedly healthy customers what they say they want, instead of what they will actually order. Satisfries were spun as a healthy fries option, with less fat and calories than the standard fry. However, after a year on the menu, 4,900 of Burger King's approximately 7,400 franchisees decided to stop selling Satisfries.

Time-strapped entrepreneurs and other busy professionals who eat out a lot should take note. It doesn't matter how much weight customers say they want to lose. When they show up at the restaurant, a good portion are only thinking with their stomachs -- not looking at a weight-loss guide. It’s not a great practice if you’re watching your waistline.

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