Almost certainly

There's an entire essay devoted to the subject of lembas in History of Middle-earth, imaginatively titled "Of Lembas"; in it, Tolkien writes:

The Eldar say that they first received this food from the Valar in the beginning of their days in the Great Journey. For it was made of a kind of corn which Yavanna brought forth in the fields of Aman, and some she sent to them by the hand of Oromë for their succour upon the long march.

 

[...]

 

Now this corn had in it the strong life of Aman, which it could impart to those who had the need and right to use the bread.

 

^{History of Middle-earth XII The Peoples of Middle-earth Part 3: "Teachings of Pengolod" Chapter XV: "Of Lembas"}

Although "magic" in the Tolkien Legendarium is a difficult thing to pin down, "the strong life of Aman" certainly sounds magical to me.

Almost certainly

There's an entire essay devoted to the subject of lembas in History of Middle-earth, imaginatively titled "Of Lembas"; in it, Tolkien writes:

The Eldar say that they first received this food from the Valar in the beginning of their days in the Great Journey. For it was made of a kind of corn which Yavanna brought forth in the fields of Aman, and some she sent to them by the hand of Oromë for their succour upon the long march.

[...]

Now this corn had in it the strong life of Aman, which it could impart to those who had the need and right to use the bread.

^{History of Middle-earth XII The Peoples of Middle-earth Part 3: "Teachings of Pengolod" Chapter XV: "Of Lembas"}

Although "magic" in the Tolkien Legendarium is a difficult thing to pin down, "the strong life of Aman" certainly sounds magical to me.