Thank you for explanations on different categories of tofu.

I am concerning that people continue consuming gypsum-bearing (or calcium sulfate) tofu, because calcium sulfate cannot be digested by human stomach acid. The consequence of consuming such tofu would result in depletion of calcium in the human system, because tiny gypsum crystals absorb calcium cations in the stomach, and form stone-like materials either deposit within the systems (like kidney), or release the system by urine. That is why eating gypsum-bearing tofu cannot acquire any calcium, but deplete calcium in the human body.