Eligibility Criteria:
Inclusion Criteria:
* Adults aged 18 years or older, of any sex, who are willing to sign the informed consent form and are able to fully comply with all study procedures.
Exclusion Criteria:
* Pregnant or breastfeeding women, or individuals unwilling to use physical contraceptive methods during the study period, such as condoms or intrauterine devices (IUDs).
* Employees of TCI Co., Ltd and their family members.
* Individuals who, within 30 days prior to study initiation, have been taking vitamin C supplements at doses greater than 200 mg per day, glutathione supplements at doses greater than 100 mg per day, or medications that may affect endogenous vitamin C or glutathione levels, such as oral contraceptives and estrogen preparations (including ethinylestradiol, desogestrel, gestodene, drospirenone, cyproterone acetate), or acetaminophen.
* Individuals with chronic gastrointestinal diseases (including irritable bowel syndrome \[IBS\], inflammatory bowel disease \[IBD\], chronic diarrhea, Crohn's disease, celiac disease, bowel control disorders/fecal incontinence, pancreatitis, peptic ulcer disease, colorectal cancer, short bowel syndrome, and ulcerative colitis), a history of epilepsy or seizures, liver or kidney disease, malignancy, endocrine disorders, psychiatric disorders, alcohol or drug abuse, or other significant organic diseases based on medical history.
* Individuals who have undergone gastrointestinal surgery, organ transplantation, or other major surgical procedures.
* Individuals who experienced acute gastroenteritis within two weeks prior to study initiation.
* Individuals with a known allergy to any components of the testing samples.