There is no question that the relative abundance of lithium in the universe is far less than neighboring chemical elements in the periodic table. In the immediate aftermath of the Big Bang, only three chemical elements existed: hydrogen, helium, and a trace amount of lithium. Unlike the heavier elements which are produced in stars, lithium is not. In fact, it gets destroyed by stars very easily which accounts for the miniscule amount. The nucleus of lithium is very unstable and the immense pressures in stellar cores tend to break apart the nucleus to a more stable element, like helium. This means that essentially all the lithium ever created was made right after the Big Bang.

There is a strong correlation with the amount of lithium contained in stars and whether or not they have planetary systems. For stars with planets, including our Sun, the amount of lithium within the star is less than stars without planets. The explanation for why this occurs is still under investigation, although it is certainly possible that the gravitational tug due to planetary movements allows for the lithium to flow more easily to the core (destroying the lithium) or surface (releasing the lithium). On average, stars with planets (including ours) have about ten times less lithium than stars without planets.