華人普遍偏低，中國的標準是50-100，西方也是有爭議的：

Even though, there is still debate about how much we actually need, most experts agree that below 25 nmol/L (or 10 ng/ml) is considered deficient.

Levels this low are associated with bone diseases like rickets or osteomalacia.

But the jury’s out on what is agreed to be a healthy level.

Some experts argue 25-30 nmol/L in the blood is sufficient, some say over 50 nmol/L is optimal for good bone health for most people, while others again advocate for 75 nmol/L or even higher.