In contrast, oral vitamin B12 supplements need to pass through your stomach acid and digestive system, and their absorption can be less reliable, especially if there are absorption issues
Theyre experimental substances that have shown promise in animal studies but have never undergone proper human trials
Nutrafol is the only supplement weve ever seen do studies on efficacy in menopausal women and men and women of different ethnicities (inlcuding African American, Asian, Hispanic Caucasian, and Non-Hispanic Caucasian participants), two groups that are often under-represented in studies in general
Summary: Excessive vitamin B12 intake rarely causes toxicity, but very high levels from supplements or injections may be associated with skin reactions such as acne-like eruptions, though serious adverse effects remain exceptionally uncommon
It also prevents a future team member from treating today's page as proof for a different lot
Why supplements and injections raise B12, and why that is not harmful By a wide margin, the commonest reason for high B12 levels is supplementation