Six In Ten Atoms In You Aren't Stardust

"We are made of stardust" is true for the heavy atoms in you. It stops being true the moment you count atoms instead of weighing them.

The oxygen in every water molecule in your body was forged inside a star that exploded before the Sun existed, and so were your carbon, nitrogen and calcium. Weighed, that is most of you: oxygen alone is about 65 % of your mass. Counted, it is not. About six in ten atoms in a human body are hydrogen, the two small atoms beside each oxygen in water.

And no star made them. Stars do not make hydrogen, they burn it into heavier elements. Essentially all the hydrogen in the universe formed in the first minutes after the Big Bang, before a single star existed. Every star since has been using up that original supply. So the most common atom in you is older than every star in the sky.

Sources, in the order the video uses them:
Every atom in you was made in a star except hydrogen and the lightest few, which formed shortly after the Big Bang - NOVA, "The Star in You" (PBS): https://www.pbs.org/wgbh/nova/space/star-in-you.html
Hydrogen is 62 % of the body's atoms but 9.5 % of its mass; oxygen 24 % of atoms, 65 % of mass - Wikipedia, "Composition of the human body": https://en.wikipedia.org/wiki/Composition_of_the_human_body
87 % of human body atoms are hydrogen or oxygen (independent check of the count; the underlying table was not read) - Freitas, Nanomedicine Vol. I, section 3.1: http://www.nanomedicine.com/NMI/3.1.htm
Big Bang nucleosynthesis produced overwhelmingly most of today's hydrogen, within roughly 10 to 1200 seconds; stars consume, not make - D. Jeffery, UNLV: https://www.physics.unlv.edu/~jeffery/astro/cosmol/big_bang_nucleosynthesis.html
About a quarter of the mass ends as helium, the rest stays hydrogen; carbon and everything heavier is made in stars - E. L. Wright, UCLA: https://www.astro.ucla.edu/~wright/BBNS.html
Protons formed a few millionths of a second after the Big Bang, nuclei within minutes, neutral atoms only after 380,000 years - CERN, "The early universe": https://home.cern/science/physics/early-universe/