Praise be to Allaah.
It says in al-Mawsoo‘ah al-‘Arabiyyah al-‘Aalamiyyah:
Hemp (also known as Cannabis) is a plant that is sometimes
cultivated for its strong fibres, which are obtained from the woody stems of
the plant and are used in making string and various kinds of rope.
Growing hemp is banned in most countries because it is
possible to obtain a psychoactive substance from it, known as marijuana or
hashish. End quote.
The cannabis plant has a serious effect on the body, hence
the fuqaha’ in the past and at present have stated that it is forbidden to
consume it, as has also been stated by legal systems worldwide.
See also the answer to question no.
The psychoactive substance in cannabis that has an effect on
the brain and nervous system is that which the questioner referred to by its
acronym THC, which stands for tetrahydrocannabinol.
It is known that this psychoactive substance is not present
in leaves other than the flowering or fruiting tops, and it is not present
in the seeds.
The military doctor Muhammad Fathi ‘Eed (may Allah guide him)
The cannabis plant is one of which cultivation is banned in
accordance with the Single Convention on Narcotic Drugs of 1961, which was
ratified by the Protocol of 1972. That is with the exception of a small
quantity that a country that is signatory to the Convention may need for
scientific research purposes.
The Convention clarified in clause (c) that what is meant by
“cannabis” is any plant of the genus Cannabis, whether it is male or female,
cultivated for the production of fibre or the production of drugs…
In the Single Convention on Narcotic Drugs it says:
“Cannabis” means the flowering or fruiting tops of the cannabis plant
(excluding the seeds and leaves when not accompanied by the tops) from which
the resin has not been extracted, by whatever name they may be designated.
The Convention stated that this definition does not include
cannabis leaves that are not attached to the tops and it does not include
the seeds. End quote from Jareemat Ta‘aati al-Mukhaddiraat fi’l-Qanoon
al-Muqaaran, 1/145, 146
Based on that, if the protein that is derived from the
cannabis or hemp plant is taken from one of these two things – other than
the flowering tops and seeds – which are in fact free of THC, then there is
nothing wrong with consuming it, so long as it does not have a negative
effect on the body apart from what may be caused by the psychoactive
substance. This is the general condition that applies to everything that is
available in the market of natural or manufactured substances that claim to
benefit the body by increasing energy. We have discussed this in our answer
concerning the ruling on sports energy drinks. Please see the answer to
question no. 163968.
And Allah knows best.