Why do you say that smoking is haram while 1-2 cigarettes per week or per day during a short period do not harm or only harm in a very small extent that no one notices? For example, if a person only smokes 1-2 cigarettes on Fridays, or he smokes a small amount of cigarettes per day just for one week, or he sometimes hookah smokes, which, according to an opinion, is approximately like 8 cigarettes, with 3 friends? Sugar harms in a very small excent too, but I do not know of any scholar who says that sugar is haram. Please teach me if there is something wrong in my question.

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

It is impermissible to smoke at all, even a small quantity, and even if it is assumed that smoking a small quantity is not harmful to the health, because the rationale behind its prohibition is not restricted to the harms incurred on the health, rather, it is also because it involves wasting money without any benefit. Allah, the Exalted, says (what means): {...and do not spend wastefully. Indeed, the wasteful are brothers of the devils, and ever has Satan been to his Lord ungrateful.} [Quran 17:26-27]

Al-Mugheerah ibn Shu‘bah narrated that the Prophet, sallallaahu ‘alayhi wa sallam, “forbade asking too many questions (about disputed religious matters or matters of no benefit); wasting wealth; and idle, useless talk.” [Al-Bukhaari in Al-Adab Al-Mufrad and Ahmad in Al-Musnad]

There is no doubt that smoking involves wasting wealth. Moreover, smoking a few cigarettes may lead to smoking a greater number of cigarettes later on, and this is often the case; the smoker starts his trip with this sin by smoking a few cigarettes and soon becomes an addict. Therefore, it is impermissible to smoke tobacco of any kind or form.

Smoking cannot be likened to sugar because sugar is a lawful substance in principle and has many benefits. The harm lies in consuming large quantities of it, just like everything else. If consumed beyond moderation, they become harmful to the health. Please, refer to fatwa 281299. As for the substance of smoking, it is evil in principle and has no benefits whatsoever. Rather, smoking involves wasting wealth, a bad smell, and a confirmed harm to the health.

Allah knows best.