NMN is a precursor your body converts to NAD+
The best form therefore depends on what problem someone is trying to solve
The glutaredoxin (Grx) system, another key player, operates in close association with the GSH pool and serves primarily to regulate protein thiol redox status through reversible de-glutathionylation

Major Ingredients Water, Propanediol, Glycerin, Dipropylene Glycol, Butylene Glycol, Isopentyldiol, Niacinamide, 1,2-Hexanediol, Hydrolyzed Collagen Extract, Hydrolyzed Collagen, Collagen Extract, Collagen Water, Glutathione, Centaurea Cyanus Flower Extract, Collagen Amino Acids, Soluble Collagen, Lactobacillus/Collagen Ferment Filtrate, Sodium Surfactin, Chondrus Crispus Powder, Polyglycerin-3, Glycereth-25 Pca Isostearate, Adenosine, Ethylhexylglycerin, Borago Officinalis Extract, Chamomilla Recutita (Matricaria) Flower/Leaf Extract, Lavandula Angustifolia (Lavender) Flower Water, Cystoseira Tamariscifolia Extract, Cornus Officinalis Fruit Extract, Anastatica Hierochuntica Extract, Sorghum Bicolor Leaf/Stem Extract, Hyacinthus Orientalis (Hyacinth) Extract, Salvia Sclarea (Clary) Extract, Carbomer, Xanthan Gum, Disodium Edta, Tromethamine, Benzyl Glycol, Glycereth-26, Betaine Ingredients subject to change at manufacturer's discretion
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Laforgia M, Laface C, Calabr C et al (2021) Peripheral neuropathy under oncologic therapies: a literature review on pathogenetic mechanisms