What I wonder is when you read that the tree of life is there and the leaves are for the healing of the nations. Will the folks physically alive in the millennial stay physically alive and eat of the tree of life as God intended that Adam and Eve would have done.
The Tree of Life is not available until the Eternal State:
Revelation 20:11-12
King James Version (KJV)
11 And I saw a great white throne, and him that sat on it, from whose face the earth and the heaven fled away; and there was found no place for them.
12 And I saw the dead, small and great, stand before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works.
Revelation 21
King James Version (KJV)
21 And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea.
Revelation 22
King James Version (KJV)
22 And he shewed me a pure river of water of life, clear as crystal, proceeding out of the throne of God and of the Lamb.
2 In the midst of the street of it, and on either side of the river, was there the tree of life, which bare twelve manner of fruits, and yielded her fruit every month: and the leaves of the tree were for the healing of the nations.
3 And there shall be no more curse: but the throne of God and of the Lamb shall be in it; and his servants shall serve him:
If this tree of life is similar or identical to that in the Garden, then that would suggest that the tree in the Garden was not meant to sustain life either, seeing that the life we have and will have in the Eternal State does not come from the tree, but from God. It is just my view that this is the case with Adam, that he was in relationship with God as we are now, indwelt and having God as the source of life. The difference being that death entered through Adam's disobedience, and death will be destroyed and not present in the Eternal State:
1 Corinthians 15:26
King James Version (KJV)
26 The last enemy that shall be destroyed is death.
Revelation 20:14
King James Version (KJV)
14 And death and hell were cast into the lake of fire. This is the second death.
Revelation 21:4
King James Version (KJV)
4 And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away.
Not that death is a persona, such as the Greeks viewed Thanatos, I think it was, but dying will not be a possibility for those glorified. It will not be a possibility for the lost, either.
The tree of life, the fruit, and the leaves speak of the consequences of sin, as Revelation 22:3 states...there shall be no more curse:
Genesis 3:17-18
King James Version (KJV)
17 And unto Adam he said, Because thou hast hearkened unto the voice of thy wife, and hast eaten of the tree, of which I commanded thee, saying, Thou shalt not eat of it: cursed is the ground for thy sake; in sorrow shalt thou eat of it all the days of thy life;
18 Thorns also and thistles shall it bring forth to thee; and thou shalt eat the herb of the field;
So I have come to look at these things as more evidence than actually something that we might view like magic trees, fruit, or leaves, but again, this is just the view I have come to take, and that view is based on the limited information we have.
God bless.