Values summarised from cited preclinical studies (see references below)
Most people following a varied diet get the recommended amount, but vegans, people with certain gut conditions and older adults who absorb nutrients less efficiently may need supplements
[4] Other symptoms may include shortness of breath, feeling faint, a smooth red tongue, pale skin, chest pain, nausea and vomiting, loss of appetite, heartburn, numbness in the hands and feet, difficulty walking, memory loss, muscle weakness, poor reflexes, blurred vision, clumsiness, depression, and confusion
What Are the Key Differences Between B12 Shots and IV Infusions
Short-term storage: Refrigeration at 4 C (39 F) is the standard for sprays in active research use