In short, not very
But here is what the ads dont tell you: smaller doses havent been studied extensively in large clinical trials, there is no evidence that microdosing is safe and effective, and microdosing comes with real safety risks, including dosing errors
Implantable and transcutaneous continuous glucose monitoring system: a randomized cross over trial comparing accuracy, efficacy and acceptance
Kojic acid is generally found in serums, creams, and masks
Additional reductions are observed in inflammatory mediators including monocyte chemoattractant protein-1 (MCP-1), inducible nitric oxide (NO) synthase (iNOS), and NO production [66, 109, 110]
Asian J Androl (2004) 6:5965