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While most airlines have cut back on serving free meals and even snacks and transitioned to pay-per-meal plans, nutrition expert Charles Platkin notes that airline food is becoming a lot healthier, with airlines providing at least one nutritious meal on their in-flight menu, according to the Los Angles Times. See which airlines, according to Platkin, have the healthiest food.

Platkin, a professor of nutrition at the City University of New York and founder of Diet Detective, has ranked and tested numerous airline foods for the past 12 years. His annual Airline Food Survey found that Virgin America provides the healthiest options; he awarded it four-and-a-half stars on a five-star scale. Virgin America serves low-calorie alternatives such as a Protein Plate with hummus, nuts, and tuna, and a roasted pear and arugula salad with almonds and fig mustard dressing. Each of these food options is less than 450 calories and packed with fiber.

Platkin rated the food on 12 airlines, providing a health score based on availability of healthy snacks and meals, food variety, calories, innovation, cooperation in offering nutritional information, and how the airline’s healthy options have improved since last year's survey.

Air Canada and Alaska Airlines came up second and third on Platkin’s list. American, United, Delta, and US Airways also made the cut, falling within the middle of the list.

The lowest ranking was given to Las Vegas-based Allegiant Air, which received one-and-a-half stars for its snacks, which include Pringles chips, and M&M's. See the 12 US airlines with the healthiest food.

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Allegiant Air
Allegiant Air ranked the lowest on Charles Platkin’s list. The healthiest options for an individual snack are the nuts or the low-carb beef jerky. As for meals, the turkey sandwich is a decent option at 280 calories.

Southwest Airlines
Southwest Airlines has limited healthy snack options. The best bets are the nuts or the Wheat Thins, but these are only offered on select flights.

US Airways
US Airways has replaced many of its high-calorie snacks with lower-calorie ones, reducing their nuts from 1,020 calories to 300 calories and their cookies from 550 calories to 330 calories. As for meals, the barbecue chicken salad is the best option, checking in at just 190 calories.

American Airlines
American Airlines offers Sabra roasted red pepper hummus with pretzels, but healthy meal options include a 323-calorie turkey and chutney sandwich. For flights that are two hours or longer, guests can order the 283-calorie Insalata Caprese salad.

United Airlines
United Airline offers selections such as a grilled chicken spinach salad and the Asian noodle salad for flights more than three hours. These salad selections, with dressing, have 360 calories. Breakfast choices include the yogurt parfait, and a 318-calorie ham and Cheddar rustic ciabatta sandwich.

Air Canada
Air Canada provides healthy fare at less than 400 calories, such as a roasted chicken wrap with salsa, and pasta salad with sun-dried tomato dressing and chicken strips.

See all 12 airlines with the healthiest food here

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