One of these is the family of trefoil factor peptides. The trefoils are peptides that are protected from degradation in the stomach by their complex, twisted structure
Emotional flatness has the same evidence gap: it appears in patient reports but was not measured as a dedicated outcome
For the majority of people, I recommend once weekly for 4 weeks
If symptoms are affecting your daily life, getting professional advice can help you understand whether B12 support may be suitable
For those who need regular injections, some providers offer training for self-administration
Certain health conditions such as intestinal or stomach problems, poor nutrition, cancer, HIV, pregnancy, old age, veganism, and alcoholism can cause vitamin B12 deficiency