Vitamin B12 safety

Do you think we should avoid B12 even if our serum levels are low? My B12 has been between 300 and 400 for years and that can contribute to depression, so I’m considering supplementing.

Seconding this. Has anyone got worse from nutritional yeast?

I recently started a vegan diet and have been taking Nature’s Bounty Vitamin B-12, 1000 mcg since apparently you don’t get enough B12 as a vegan… This can really be harmful?