Subcutaneous injection bypasses all of these barriers except plasma half-life, which for unmodified small peptides is generally very short (minutes to low hours, based on class-level pharmacokinetic data for similar unmodified peptides)
Cardiovascular Diabetology
It was meant to rule out deficiency, but the result points the other direction
A deficiency in Vitamin B12 can cause fatigue, brain fog, and neurological symptoms
This deficiency can be caused by poor dietary consumption, a breakdown in the digestive process, or from taking certain medications that make it difficult to absorb B12 (such as antacids)
Additionally, vitamin B12 influences melatonin production, which regulates sleep cycles, leading to better sleep quality and consistent sleep patterns