Our Cosmic Origins

What is the cosmic origin of the elements in the human body? We know we are made of stars. But what kind of stars?

You are made of elements that have been forged in exploding massive stars, in slowly dying low-mass stars, but also exploding white dwarfs, and merging neutron stars. On top of all that, also of an element that has been created during the birth of the Universe itself, and hasn’t been created in a star.

The percentages by mass of the elements in your body are revealing:

65.00% oxygen
18.50% carbon
09.50% hydrogen
03.20% nitrogen
01.50% calcium
01.00% phosphorus
00.40% potassium
00.20% sodium
00.20% chlorine
00.10% magnesium
00.04% sulfur

Other elements are present in your body in traces of less than 0.01%: boron (B), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), fluorine (F), iodine (I), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), silicon (Si), tin (Sn), vanadium (V), and zinc (Zn).

Oxygen and hydrogen of course make up water (H2O), for more than 70% of the body mass.

The chart that shows the cosmic origin of the elements in your body also shows that you were born for almost ten percent of your body mass during the Big Bang itself. You are direct descendant of the birthing of your Universe!

Somewhat worryingly, since the trace elements are still essential to your well being, you need the merger of neutron stars to be frequent enough to then spew out the elements that coalesce around the star heating the planet that allows you to evolve. Is this event frequent enough during the thirteen billion years of the Universe to give a chance to more than one planet to harbor a type of biology that is even remotely similar to yours?

What else can you establish studying this chart? What other combined charts could be as revealing as this?


Shyamala Iyer. “Atoms & Life“. ASU – Ask A Biologist. 27 September, 2009.
Nucleosynthesis on Wikipedia

The idea to create this chart came through a post by Ashton Martin.