Research published in Journal of Clinical Biochemistry and Nutrition indicated that methylcobalamin leads to higher and more sustained tissue retention compared to cyanocobalamin, especially in neurological tissues
Based on the data available in 2015, EFSA did not identify any known health risks associated with the use of dietary supplements, so no maximum dose or maximum daily intake, also known as a tolerable upper intake, was set (EFSA, 2015)
Both types are used based on whats best for each patient
Avoid exposure to light
The goal is a body that produces energy reliably on its own not one that needs an external boost to function
GHK-Cu (sister peptide) given by intraperitoneal injection at 0.2/2/20 micrograms/g in mice reduced pulmonary fibrosis via Nrf2/NF-kB/TGF-beta1-Smad2/3 demonstrates systemic-injection dosing of the copper-tripeptide class in animals, relevant to the injectable question but GHK-Cu, lung, mouse