Review Finds Vitamin D2 Supplements May Lower Blood Levels of D3

Vitamin D helps keep bones healthy and supports the immune system.

A review of 11 trials found that people taking vitamin D2 supplements tended to have lower blood levels of vitamin D3.

D2 can still raise overall vitamin D levels, but researchers said D3 may work better for most people.

The findings may help people choose between supplements, though personal needs can differ.