"Calcium deficiency" refers to a condition where a person's body doesn't have enough calcium, which is a mineral necessary for strong bones and teeth. Full definition
That is why the most common symptom of calcium deficiency is osteoporosis, characterized by softer and more fragile bones. (healthline.com)
So after eating quinoa for breakfast following the box directions I am now suffering from calcium deficiency in the form of fallen arches. (realfoodkosher.com)
Likewise, every day you don't deposit calcium, your withdrawal increases and you risk calcium deficiency symptoms. (saragottfriedmd.com)