That's because neither you nor anything in your diet (nor anything in your diet's diet) has titanium teeth and jaws.
The Earth's crust is 3.6% calcium, and we get more than enough of that in our diet...it's 5% iron. There's even a lot of titanium - fully 0.6%, much higher than 'rare' elements like carbon! [0]
I don't think we'd have any trouble getting it if the metabolic and biological systems that are employed to get us calcium were instead employed to produce titanium.
The Earth's crust is 3.6% calcium, and we get more than enough of that in our diet...it's 5% iron. There's even a lot of titanium - fully 0.6%, much higher than 'rare' elements like carbon! [0]
I don't think we'd have any trouble getting it if the metabolic and biological systems that are employed to get us calcium were instead employed to produce titanium.
[0]: https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth...