Sundown has liquid filled calcium.
There are 2 types of Calcium: Calcium Citrate (柠檬酸钙)or Calcium Carbonate (碳酸钙).
Calcium Citrate: Calcium is best absorbed in an acidic environment, hence
calcium citrate is the best absorbed supplemental form of calcium. It does
not require extra stomach acid for absorption, hence we may take it anytime
in a day, even on an empty stomach.
Calcium content: Calcium Citrate usually provides less elemental calcium per
pill than Calcium Carbonate, therefore one may