What kind of whitening result can I realistically expect from this powder?

The whitening claim refers to extrinsic stain removal — the dull film that builds up from pigmented drinks, foods, or tobacco. Calcium carbonate acts as a mild polishing agent; with regular, gentle brushing it can restore the tooth's original brightness by clearing that surface layer. It will not lighten the internal color of the tooth, nor will it affect stains that have penetrated micro-cracks or developmental defects. Results vary: someone with heavy coffee staining may see a noticeable difference within a week or two of intermittent use, while someone whose teeth are already clean may perceive little change. Overuse in pursuit of a whiter look risks enamel thinning and sensitivity, which ultimately makes teeth appear yellower as the darker dentin shows through. For deeper whitening, peroxide-based treatments prescribed or supervised by a dentist are the standard route. Think of this powder as a maintenance tool for surface clarity, not a bleaching product.