glutathione pathway red blood cells in Brain Disorders and Aging Response of Human Red Blood

As a recent scientific review explains, 4 Owing to its size and charged nature, NAD+ cannot passively pass through cellular membranes, including the plasma membrane. ...this probably occurs indirectly through the generation of NAD+ degradation products, such as NMN, NR or NAM, which act as precursors. In other words, NAD+ taken orally must first be broken down into these smaller molecules before it can re-enter cells and contribute to NAD+ synthesis

Proc Natl Acad Sci USA 104: 13268-13272

You do not need a prescription for most vitamin B12 injections

The CAS number for GHK-Cu is 89030-95-5 (GHK-Cu complex)

And it might, more broadly, mean you are deficient at the cellular level

There are few animal or human studies that have assessed the role of sulforaphane on colon cancer