There are people in Iceland who have 19-20 hour days. If they’re not able to fast that long, they can make up for it by feeding a poor person (i.e. charity).
Fasting is mentioned in a variety of places throughout the Qur’an; the most relevant passage to this thread would be surah 2:183-185, which says "*O ye who believe! Fasting is prescribed to you as it was prescribed to those before you, that ye may (learn) self-restraint.
(Fasting) for a fixed number of days; but if any of you is ill, or on a journey, the prescribed number (should be made up) from days later. For those who can do it (With hardship), is a ransom, the feeding of one that is indigent. But he that will give more, of his own free will, it is better for him. And it is better for you that ye fast, if ye only knew.
Ramadhan is the (month) in which was sent down the Qur’an, as a guide to mankind, also clear (Signs) for guidance and judgment (Between right and wrong). So every one of you who is present (at his home) during that month should spend it in fasting, but if any one is ill, or on a journey, the prescribed period (Should be made up) by days later. Allah intends every facility for you; He does not want to put to difficulties. (He wants you) to complete the prescribed period, and to glorify Him in that He has guided you; and perchance ye shall be grateful*".
Ok, so, multiple times, Allah acknowledges the frailty of humans and expresses concern for them. He doesn’t mention every single case under which a person is exempt from fasting-- He doesn’t have to. He just says, “for those who are unable, feed the poor” (see translations by Yusuf Ali, Sahih International, Muhsin Khan, Pickthall, Shakir and Dr. Ghali on Quran.com and how they translate surah 2:184). Allah could’ve made a list of 17 things that permit someone to forego fasting, but eventually, someone would develop another condition, making God’s list of 17 things irrelevant.
Allah doesn’t have to mention every case where exceptions are made, such as people who, for whatever reason, might be camping in Antarctica or a mother who’s nursing. Those who are unable to fast can feed the poor instead.