Th?c ph?m ch?c n?ng b? ph?i, six s?n ph?m h? tr? c?i thi?n v?n ?? hô h?p Tiê?n châ?t cu?a vitamin D la? 7-dehydro-cholesterol (n??m d???i da) ????c hoa?t ho?a va? tr?? tha?nh vitamin D khi co? s?? ta?c ?ô?ng cu?a tia t?? ngoa?i trong a?nh n??ng m??t tr??i. Th?c ph?m b?o