Well , yes and no , being overweight is not good for you , but some of the airlines obsession with medicals / BMI / etc is nonsense , as anybody who applies to KAL or even makes the mistake of Indian airline employment where the latest ' ploy ' is to make us ageing expats pass a military medical - there is NO way a 60+ pilot is going to pass a medical designed for 25 year olds however fit they are - I am fairly fit ( we can all be fitter ) but my vitals are good and especially my ticker . I have Class 1 Medical , both UK and ICAO , but am deemed a risk by ALL Asian airlines because I am over 55 .
C'est la vie.