Have you wondered how to be truly naturally happy and motivated in life without the need for any artificial needs like caffeine, nicotine, music, out of marriage sex, shopping sprees, cheap thrill, etc? Everyone has this internal energy which is natural. When we are born we are full of it, but as we grow, it might diminish, especially after puberty. When it diminishes, we may become grumpy, miserable, and easily influenced by others so that our mental facilities might become diminished and others might end up "thinking for us" or exploiting us in their own strategic plans for success.
The general concept of human self development to grow this internal energy to become something strong and powerful in order to fulfill what Maslow calls the hierarchy of needs starting from the basics of food, clothing, and shelter all the way to the complete development of man.
In contrast to the development of man in social sciences and philosophy, there are faith based concepts of self development which can be divided into Abrahamic (Judaism, Christianity, Islam), and polytheistic traditions (Ancient Egyptian, Chinese, Indian, Aboriginal, etc). Some of the latter are based on personal experiences of individuals like Gautam Buddha, the founder of the Buddhist tradition. Many are from a divine origin, with God sending prophets and scriptures to guide a particular community of humanity to teach them how to develop themselves naturally.
The prophets were such individual human teachers in history who were chosen by God to guide a particular segment of humanity to grow their soul/self/spirit naturally. For example, Solomon (AS) was not given a new Scripture, but used the previous scriptures, i.e. the Torah and the Psalms, to guide this kingdom. Whereas messengers were those teachers who were sent to human communities with a specific Scripture for their development. So Abraham (AS) was a Messenger because he was given the Scrolls as a Scripture, Moses (AS) was a Messenger because he was given the Torah as a Scripture, David (AS) was a Messenger because he was given the Psalms as a Scripture, Jesus (AS) was a Messenger because he was given the Gospel as a Scripture to guide the lost Children of Israel and lastly Muhammad (SWAS) was a Messenger because he was given the Quran as a Scripture to guide ALL of humanity for self development.
The Quran is still intact in its original Classical Arabic verbatim. A recent manuscript discovered in Sana'a, Yemen, was carbon dated to be found from the early era following its revelation. It was found to be essentially the SAME as the Quran we have today (https://www.youtube.com/watch?v=C-HDFiC2boQ). The Quran is a compilation of direct communication (revelation) from God to Prophet Muhammad (SWAS) to directly guide him in his mission of 23 years to teach humanity proper self development. It has been memorized by billions of people throughout history and there are no "versions" of it per se. As "pure words of God", it is still an everlasting miracle that guides believers individually just as it guided Prophet Muhammad (SWAS).
In Islam there is no clergy as such to approach God. Every believer relates directly to God through direct worship and guidance undergoing complete self development in the process. Thus the challenges of life are a blessing for them to grow themselves and make them strong and resilient. But unlike Nietzsche's "Superman", they are never arrogant. Rather they are like the "servant leaders" of today's most successful corporate leadership, in that they lead by personal example and influence as did the prophets and messengers who taught people how to implement their scriptures (books of wise natural principles) for complete personal and community development.
Muslims believe that Prophet Muhammad (SWAS) was the final prophet/messenger for all humanity, with other prophets and messengers relevant to only their particular communities and epochs only. Although we learn from them as well as we learn from the unique experiences of Prophet Joseph (AS) or Prophet Job (AS) for example.
The Quran and its application as taught by Prophet Muhammad (SWAS) is universal for all humanity, for all times, and for all places, as it is the most optimum/balanced for complete self development of individual and collective human soul(s). It is based on direct one-on-one learning from God, throughout the day, using the methodology of Prophet Muhammad (SWAS) taught to implement the Quran in our lives.
The real struggle/striving (jihad) in Islam is to fight the lower self and develop it through the methodology taught by Prophet Muhammad (SWAS). Unlike Nietzsche's "Superman" who fights his way up by putting people down, the Prophetic methodology is through exemplary self sacrifice and empathy for all humanity, developing incredible emotional intelligence. By doing "good deeds" for his hereafter using natural human natural principles, he created an extraordinary effect in terms of influencing those around him, causing an incredible attraction to his "goodness" due to his sincerity with God, depicted in his authentic mindful daily behaviour. Thus, rather than "putting others down", Islam is about submitting oneself to the natural forces of God while "picking up others". Prophet Muhammad (SWAS) has been reported as saying, "whoever humbles himself for God, God raises their rank".
Although other faiths do contain wisdom and paths to self development, they are not as effective as the Islamic methodology especially when it comes to mental health. Their sub optimal nature is due to several factors among them are the following:
1. Their scriptural sources are not intact any more, having been altered/corrupted/lost over centuries/millennia.
2. The practices of other prophets/messengers are not preserved authentically like that of Prophet Muhammad (SWAS) in writing and in the lives of billions in history and millions today globally.
3. They were specific to a particular community in history, geography, and anthropology i.e. not universally applicable for all humanity like Islam.
4. Except for Judaism, they take guidance from multiple sources of divinity rather than just ONE source of guidance/self development. Although Judaism is monotheistic like Islam and unlike Christianity (in a strict sense), its guidance is only specific to the Jews and not for all humanity, by its own definition.
How can one develop based on multiple divine sources? If one source might inspire them to something, another might inspire them to something opposite!
Thus, I believe that Islam is the most optimum self development option we have for mental health improvement. God has put in every potential human being a "soul" -- a spirit with some divine affinity which is different from the physical body that it is trapped in until it is separated from the body at death. The state of our soul on Judgment Day will determine our state in the heaven-hell spectrum graduation, after the mercy of God.
This world is a place to develop our souls for the next world. It is through correct belief and doing good deeds using the correct Prophetic methodology that causes the soul to grow and develop to become naturally energetic without the need for substances/medicines/rich food. Mental health issues arise when the soul is weak and withered so we lose the natural vitality of life in adulthood.
This natural vitality or joi de vivre is diminished when the internal battery is not recharged regularly from the Divine. Just like a rechargeable battery needs to be recharged regularly, the human soul needs to be recharged several times daily by reconnecting to the Divine Source regularly in the most optimum way taught by Prophet Muhammad (SWAS). The soul is corrupted when worship/guidance/charge is sought from other than the ONE DIVINE BEING. So when we worship wealth, lust, ego, the founders/teachers of religion of God rather than God Himself who they asked people to worship, our soul gets withered and eventually dies, getting no inspiration, insights, or guidance from God any more.
With a "dead" soul we cannot produce the right chemicals in our brains naturally to develop foresight and vision to where we want to go, so we lack the natural energy to pursue our goals. We end up being influenced by others and become part of their roadmap, thus compromising our own mental independence. With a well developed, purified, and refined soul, we are able to develop ourselves and our communities for universal good. Without growing the soul properly, all this is not possible and the default for the soul is to descend if effort is not exerted.
Unless we have good goals, do good deeds daily to help achieve them, enjoin the truth and mutual cooperation to pull each other up as a community, we risk withering our souls and letting it die. In that state, it becomes difficult for the mind to be inspired to good. Rather, it might be inspired to negativity, by negative (Satanic) forces in nature. Psychotropic medicines try to block such negative whisperings that can affect the soul by default, by putting synthetic chemicals in the brain which the body cannot produce any more, to prevent the soul from descending further.
So the real natural cure for mental health issues in the Islamic paradigm is to grow the soul by making it increase in natural strength based on a complete program of development based on a complete way of life designed for it. In Islamic terminology this good internal feeling of wholeness/wellness/positive energy is called emaan i.e. faith. The whole Islamic lifestyle is designed by God naturally and taught by Prophet Muhammad (SWAS) to constantly and increase emaan i.e. the richness of the soul, directly from insights from God, rather than any intermediary. As the whole lifestyle is based on this end, there are countless integrated holistic means to achieve this in Islam, e.g. the 5 daily prayers (salaat), daily affirmations/supplications (adkaar), following a Prophetic lifestyle (sunnah), self discipline through fasting, charity, pilgrimage, good deeds, serving humanity, etc.
Thus, mental health issues can be resolved if a person can sincerely self development based on Islam in a sustained and balanced manner from direct insights from God as taught by Prophet Muhammad (SWAS).