Vitamin C, D, and Glutathione Injections: Supporting Immunity from the Inside Out Syn Wellness Center Why your Vitamin D supplements might not be working. Did you know that oral supplements have to go through your entire digestive system? This means you might not be absorbing what Vital Nutrients Glutathione 100 Capsules 400 mg Glutathione deficiency induces epigenetic alterations of vitamin D metabolism genes in the livers of high fat diet fed obese mice Scientific Reports The Impact of Vitamin D and L Cysteine Co Supplementation on Upregulating Glutathione and Vitamin D Metabolizing Genes and in the Treatment of Circulating 25 Hydroxy Vitamin D Deficiency