i don't think it would do much, as if it would matter, it would mean the digestive system is still in operation, or other functions, and one can assume that it'll be more or less on near full-standstill, so it would only mean they wake up with a hangover despite having travelled dozens of years.
which brings me to what tennessee mentions; their destination is on the other side of the galaxy. he mentions his baby brother (probably somewhere between 15yo and 25 y tops), then being old, fat and losing hair, and his brothers kids, so that means his brother must still be A) alive and B)have reproduced lol. also old enough to thus be definately old. so if he's youngest at about 15 years old, that means the travel cant be longer than let's say 50 years old, his brother being 65 then, and having kids, that can be about 20ish perhaps. if we go by that he's at tops 25, then that means it's max 40 years of travel.
after all, babybrother is a cool term for his brohter, but surely not literal; if his brother is a baby now, let's say 1 years old, well,danny mcbride is 40 years old, so his parents should be 60-ish and i have a very solid hard time believing a 60year old mother gave birth recently. not impossible offcourse, but rather an exception, not the norm. so i think babybrother is rather a sentimental statement instead of factual.
so intended journey is between 40 and 50 years i suppose. let's leave it at 45 years of travel.