Medically reviewed by Sohaib Imtiaz, MD Key Takeaways Take vitamin B12 on an empty stomach in the morning or early afternoon to maximize absorption and avoid sleep disruptions.Vegans, older adults, ...

B12 shots can have mild side effects like diarrhea and swelling at the injection site. Vitamin B12 injections are an effective way to treat a deficiency, but they're not for everyone. In fact ...

B12 deficiency can elevate homocysteine levels, which is linked to an increased risk of heart diseases, high blood pressure, and other cardiovascular issues. Mouth ulcers, a swollen tongue, and ...