The most common reasons: using a standard (non-effervescent, non-liposomal) capsule with poor gut absorption, inconsistent daily use, expecting visible results before the typical 8-12 week window, unrealistic expectations set by marketing claims, low supporting nutrients like Vitamin C, or continued sun exposure without adequate sunscreen, which counteracts skin brightening effects
If you're using standard, non-liposomal glutathione, an empty stomach 2030 minutes before your chai or breakfast is generally when it has the best shot at avoiding digestive breakdown
Yerushalmi R, Woods R, Ravdin PM, Hayes MM, Gelmon KA
Each peptide category produces effects on different schedules
Additionally, Minuk and Lewkonia (1986) have even reported familial clustering of Inflammatory Bowel Disease (IBD) and MS, suggesting that they have genetic or environmental risk factors in common