1 John 1: 9 If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.

Isaiah 55: 6 Seek the LORD while He may be found,
Call upon Him while He is near.
7 Let the wicked forsake his way, And the unrighteous man his thoughts;
Let him return to the LORD, And He will have mercy on him;
And to our God, For He will abundantly pardon.

Ezekiel 33: 14 Again, when I say to the wicked, ‘You shall surely die,’ if he turns from his sin and does what is lawful and right, 15 if the wicked restores the pledge, gives back what he has stolen, and walks in the statutes of life without committing iniquity, he shall surely live; he shall not die. 16 None of his sins which he has committed shall be remembered against him; he has done what is lawful and right; he shall surely live.

Micah 7: 19 He will again have compassion on us, And will subdue our iniquities.
You will cast all our sins into the depths of the sea.

Psalm 103: 11 For as the heavens are high above the earth,
So great is His mercy toward those who fear Him;
12 As far as the east is from the west, so far has He removed our transgressions from us.

As you can see from the above texts, and there are many more, God is very keen to forgive us, if we come to Him and confess our sins.

As to the second part of your question, most of the substances you talk about are not mentioned in the Bible, but the principle is given in the following passages:

1 Corinthians 6: 19 Or do you not know that your body is the temple of the Holy Spirit who is in you, whom you have from God, and you are not your own? 20 For you were bought at a price; therefore glorify God in your body and in your spirit, which are God’s.

1 Corinthians 10: 31 Therefore, whether you eat or drink, or whatever you do, do all to the glory of God.

God communicates with you through your mind, and the mind should therefore be as clear as possible, both to understand what He says in the Bible, and to pray to Him. Anything that dulls the mind will therefore hinder communication with Him, and this is absolutely essential to know Him. Knowing God is the key to living in eternity with Him.

John 17: 3 And this is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent.