“难消化”的英语可以翻译为：indigestibility，stodginess ...

油炸食品非常难消化。Fried food is very indigestible.这些难消化的食物沉甸甸地压在我胃里.The indigestible food set heavily on my stomach.难消化的食物使他的胃不舒服.The heavy food unsettled his stomach....