With age, stress, and chronic health challenges, some of these natural signaling pathways can slow down
Administering injections, especially intramuscular ones, can be intimidating without proper training
This saves preparation time and reduces the margin for manual dosing error, making it an efficient choice for high throughput research environments
But if it's due to pernicious anemia, your doctor will need to inject you with vitamin B12.
This also increases the risk of overdosing
For example, one study found that taking 1,0002,000 micrograms orally in properly timed doses helped improve levels as much as injections