Here’s yet another reason to get in shape before you hit the beach: if you’re flying Samoa Air, you will now pay only for what you weigh, according to its website.

The airline is calculating the cost of the ticket based on both the weight of passengers and their baggage: customers pay a fixed price per kg, which varies according to the length of the route, according to the Telegraph. The rates range from $1 a kilogram — for the weight of the traveler and their baggage — on the airline’s shortest domestic route to about $4.16 per kg for travel from Samoa to the neighbouring nation of American Samoa.

According to calculations by New Zealand’s 3 News: a 75-kg person with 15 kg of luggage flying from Fagali’i in Samoa to Pago Pago in American Samoa will be charged $1.66 per kg, racking up a total fare of $149.40. No direct comparison was available between the airline’s new and old fares, though the same flight on Polynesian Airlines comes out cheaper at a flat fare of $135, the report says.

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As the weight of an average passenger and the price of fuel continue to increase, analysts say it’s only time before other airlines follow Samoa’s new pricing system. Price discrimination, such as charging kids and the elderly different prices, isn’t new, and airlines like Air France, Southwest and United already have policies that require passengers to buy an extra ticket if they can’t fit in the seat with both armrests down.

But Samoans flying between the islands are facing more than just cost issues: these Pacific islands — particularly American Samoa, which is a U.S. territory — have “westernized” over the years, including becoming entrenched in the obesity epidemic that has been caused by consuming imported, processed food. By 15 months of age 23.3% of boys and 16.7% of girls in American Samoa are obese. In the general population, 93.5% of American Samoans are overweight or obese.

This hefty issue — combined with the fact that Samoa Air’s fleet of three- to nine-passenger planes are tiny compared with the usual commercial planes — makes the policy seem practical, rather than insensitive: “The smaller the aircraft you’re in, the less variance you can accept in terms of the differences in weights between passengers,” explains chief executive Chris Langton, in an interview with Radio Australia’s Pacific Beat.

“People who have been most pleasantly surprised are families because we don’t charge based on seat requirement even though a child is required to have a seat,” Langton says in the interview. “We just weigh them. So a family of two adults and maybe a couple of midsize kids or younger children can travel for considerably less than what they were being charged before.”

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