For an adult, the usual daily target is 2.4 mcg of vitamin B12 per day. If by “Safi” you mean a B12 supplement or fortified drink, the exact number depends on how much B12 is in each serving, but many supplements are sold in doses like 5–25 mcg or higher, which can exceed the daily target.

How to figure it out

Use this formula:

servings needed=2.4textmcgB12 per serving in mcg\text{servings needed}=\frac{2.4\\text{mcg}}{\text{B12 per serving in mcg}}servings needed=B12 per serving in mcg2.4textmcg​

Examples:

  • If one Safi has 1 mcg B12, you’d need about 2.4 servings.
  • If one Safi has 2.4 mcg B12, you’d need 1 serving.
  • If one Safi has 10 mcg B12, one serving already covers the daily amount.

Safety note

B12 is generally considered low-risk, and the NHS notes that up to 2 mg a day from supplements is unlikely to be harmful. Still, if you’re using Safi specifically to treat a deficiency, the right amount can be different from the basic daily need and should match the label or a clinician’s advice.

What I need

If you send the B12 amount per bottle/can of Safi from the nutrition label, I can tell you the exact number of bottles or servings needed.