glutathione top 10 ConsumerLab | Recent tests found that many supplements sold on Amazon failed label claims. Only 6 of 12 products contained their claimed 10% Vitamin C + Glutathione

Sobel et al., 2022)

But some bodies don't pull B12 from pills efficiently

There are 2 primary mechanisms: Ascorbic Acid (Ascorbate) uptake using sodium-dependent vitamin C transporter (SVCT) 1 or 2 Ascorbic Acid (Ascorbate) Recycling Ascorbic Acid (Ascorbate) transport using sodium-dependent vitamin C transporter (SVCT) 1 or 2 As shown below, SVCT 1 and SVCT 2 transport ascorbic acid or ascorbate into the cell against the concentration gradient (represented by the orange wedge in the figure below)

Disulfide-bridged organosilica frameworks: design, synthesis, redox-triggered biodegradation, and nanobiomedical applications

In comparison, the region that contains the greatest amount of variability between GST classes is contained in the alpha-2 helix on the C-terminal domain