We don’t always have the answers, but we have some people on speed dial who do — which is why we present our FYI series, where we have experts explain if lip balm is actually bad, how often you should ...

Hydroxyapatite (HAP) toothpaste is a dental product that contains manufactured calcium phosphate. Calcium and phosphate are minerals that form 95% of tooth enamel and 70% of bones. NASA developed HAP ...