An Indian airline has hit on possibly the worthiest excuse yet for hiring slim women as cabin crew -- it saves fuel and therefore money.

While some airlines admit to hiring women for their sex appeal , budget carrier GoAir has told The Times of India it will be hiring predominantly female flight attendants in future because they are 15-20 kilos lighter on average than men.

The airline estimates each extra kilo on board costs Rs3 ($0.05) per flying hour, and the new policy will save it up to $500,000 annually.

A spokesman for the airline denied to CNN that it had implemented a gender-biased recruitment policy. But he confirmed that the airline's male-female cabin crew ratio of 40:60 was among the most male-heavy in the industry in India.

He also confirmed that GoAir would be seeking to adjust this ratio to be in line with the industry norm of 30 men to 70 women.

Other weight-reduction initiatives will also be employed.

"The size of in-flight magazines has been reduced," the airline's CEO Giorgio De Roni said. "The potable water tanks are no longer being filled to capacity as only 35% to 40% of that water is actually used."

GoAir's 130 male cabin staff (out of 330 total) will be unaffected -- the policy affects future hires only. The airline expects to hire around 2,000 flight attendants and pilots over the next seven years.

Go Air has implemented a women-only cabin crew policy to save money. RAVEENDRAN/AFP/GettyImages

Weight and its reduction is a key focus for airlines as fuel costs, comprising a third to half an airline's operating costs, continue to rise.

Samoa Air last year became the first airline to charge fees according to weight , and a Norwegian economist has claimed this is the fairest and most sensible way to calculate prices.