When levels are low, it can lead to fatigue, brain fog, low mood, and general weakness
So far, most of the evidence comes from lab and tissue-sample studies rather than large human trials
Both can be valuable when used correctly
FDA PCAC 2023 What this means practically for research dosage decisions: Doses above 1 mg/day are not supported by efficacy data and appear to produce diminishing returns
The frequency of Vitamin B12 injections depends on your individual health needs and the underlying reasons for supplementation
Advantages of oral form over IM injection: Less nursing time on injections Less complexity of care Less discomfort/pain Less bleeding in patients who take anticoagulants Less costly according to some analyses Disadvantages of oral form over IM injection:: Greater risk of non-compliance In 1991, a survey done on Minneapolis internists led one commentary to conclude that oral vitamin B 12 replacement for pernicious anemia was one of medicines best kept secret. 18 In 1996, when the survey was repeated again in the same area, awareness and use of oral vitamin B 12 for pernicious anemia had increased substantially (019%), but the majority of doctors still remain unaware of this treatment option (61%)