For most healthy adults, daily vitamin B12 intake up to 1,000 micrograms from supplements appears safe, while higher doses need medical supervision.

For most healthy adults, daily vitamin B12 above about 1,000 mcg is usually unnecessary and should only be used long term under medical guidance.

For healthy adults, daily vitamin B12 intake around 2.4–4 micrograms is enough, and even much higher doses are usually safe for most people.

Most adults with neuropathy need 1,000–2,000 mcg of vitamin B12 daily at first, then 250–1,000 mcg long term, guided by blood tests and symptoms.

One standard 6-ounce tub of plain yogurt supplies around 0.5–0.7 micrograms of vitamin B12, while many Greek yogurts reach about 1 microgram per cup.

One large egg contains about 0.6 micrograms of vitamin B12, giving roughly one quarter of an adult’s daily requirement.

Most adults need about 2.4 micrograms of vitamin B12 per day, with higher targets in pregnancy, breastfeeding, and some medical conditions.

A daily intake of 2.4 micrograms of vitamin B12 equals 2,400 nanograms and matches the standard adult recommendation.

Typical vitamin B12 injection doses range from 1,000 micrograms daily for 1 week to 1,000 micrograms monthly for maintenance, set by your doctor.

Most vitamin B12 injections contain 1,000 micrograms per mL, and a standard shot is 1 mL for a total of 1,000 micrograms.