This is a basic bone-and-teeth play: 600mg of **Calcium** per tablet, which sits at the top of the supplemental range and covers a solid chunk of the 1,000mg most adults need daily (you're likely getting 700-900mg of that from food already). The catch is the form. Calcium carbonate needs stomach acid to dissolve, so you have to take it with a meal, and it absorbs less efficiently than citrate-based forms. Absorption also drops sharply above 500mg in a single dose, so splitting the label's 1-2 tablets across two meals gets you more usable calcium than taking them together.

The tablet also includes 400 IU of **Vitamin D3**, which is what lets your body actually absorb the calcium. Without it, you take in only 10-15% of what you swallow. But 400 IU sits below the 1,000 IU that clinical research uses as a starting dose, so it's enough to support uptake but short of an optimal level if you're correcting a deficiency or relying on this as your main D source.

Calcium on its own has mixed evidence for preventing fractures. It works best paired with adequate vitamin D, protein, and vitamin K2 to direct calcium into bone rather than arteries. For your bone goals, treat this as a calcium top-up rather than a complete bone formula, and make sure your D3 is covered elsewhere if you're not getting much sun.