You cant enroll in a Medicare Advantage plan if you already have Original Medicare
Chang, Chung-Hsun et al

This may be due to copper's ability to enhance the expression of metalloproteinases (MMPs).16 MMPs normally regulate the degradation of collagen, and a specific one, MMP-1, may be responsible for the initiation of collagen fragmentation.17 Supporting this, a 2024 study noted that elevated MMP-1 levels appear to contribute to aging skin and that higher MMP-1 levels in mice led to:18 The loss and fragmentation of dermal collagen fibrils Contracted fibroblast morphology Reduced collagen production Increased expression of pro-inflammatory mediators Additionally, a 2016 study found that GHK-Cu significantly increased gene expression of MMP-1 and MMP-2 at the lowest concentration, which the studys authors considered to be one of the reasons the peptide was able to increase collagen and elastin production.19 So, what this could ultimately mean is that using too much GHK-Cu (or other copper peptides) may in theory increase the skins MMP-1 concentration above the levels involved in healthy collagen production, taking it into the collagen fragmentation and breakdown territory seen in older skin with naturally higher MMP-1 levels

A natural, long-acting form of B12, hydroxycobalamin is popular in Europe and is often used to treat deficiencies and pernicious anaemia
NICE Clinical Knowledge Summaries recommend B12 injections for: Pernicious anaemia an autoimmune condition affecting intrinsic factor production Malabsorption syndromes including coeliac disease and inflammatory bowel disease Post-surgical states particularly following gastrectomy or ileal resection Strict vegan diets when oral supplementation proves inadequate, though oral cyanocobalamin is usually sufficient for dietary deficiency Clinical trials demonstrate that B12 injections rapidly improve haematological parameters and neurological symptoms when deficiency is confirmed through blood tests
Polanski JF, Soares AD, de Mendonca Cruz OL