Airline food has a reputation for not being the best and a new study shows that it isn't the healthiest either.

DietDetective.com conducted a survey of 12 American airlines to determine which airline carries the unhealthiest foods. It was found that low-cost airline Allegiant Air has the least healthy inflight snacks and meals. The airline only scored a 1.5 out of five rating.

The ratings were determined based on the caloric levels of snacks, meals, and snack boxes, as well an menu innovation and any improvements that were made from last year.

According to the survey the average inflight food item contains 360 calories which is a slight drop from the 388 calorie snacks last year.

The Las-Vegas based airline Allegiant lost major points for its high calorie snacks like a 523 calorie deli snack pack that contains salami slices, pita chips and SnackWell creme sandwich cookies. Among the other snacks that the airline offers in a 490-calorie bag of Peanut M&M's, a four-ounce bag of Skittles, which contains 424 calories, and 680 calorie bag of Blue Diamond Wasabi Almonds.

The healthiest snack on the plane is a hummus snack pack that contains whole grain pita chips. The snack pack is 210 calories.
Southwest Airlines came as the second airline with the least healthy snacks as it only scored a 2. Virgin America is the airline with the healthiest food options. Virgin scored a 4.5 our of 5.

Here are the airlines with the least healthy and healthiest food options:

1. Allegiant Air: 1.5
2. Spirit Airlines: 1.5
3. Southwest Airlines: 2
4. Frontier Airlines: 2.75
5. Delta Air Lines: 2.75
6. US Airways: 3
7. American Airlines: 3
8. United Airlines: 3.25
9. JetBlue Airways: 3.5
10. Alaska Airlines: 4
11. Air Canada: 4.5
12. Virgin America: 4. 5