Thailand has entered an aging society, prompting increased research on improving the elderly quality of life and preventing age-related diseases, with a particular focus on skin aging. Skin aging is linked to the degradation of dermal and epidermal tissue, leading to decreased collagen, elastin, and glycosaminoglycans, which causes reduced skin elasticity and wrinkles.

Assam tea is native to northern Thailand and is traditionally used in local products like fermented "Miang." Research shows that Assam tea contains high levels of polyphenols, particularly catechins, which have strong antioxidant properties that help combat conditions such as cancer, cardiovascular disease, and skin aging.

The study aims to study the effect of cosmetic products from Assam tea on irritation, moisturization, skin elasticity, wrinkles, and satisfaction in volunteers to enhance its value, particularly for the elderly. This effort is intended to boost the local economy, promote community-based tourism, and expand Assam tea products to national and international markets, ultimately improving livelihoods and addressing environmental concerns in northern Thailand.

Inclusion Criteria:

• Aged 35 years and older
• Good physical and mental health
• Willing and able to provide informed consent to participate and complete the entire duration of the study

Exclusion Criteria:

• Women who are pregnant or breastfeeding
• Presence of existing dermatological conditions
• History of autoimmune disorders
• Prior use of products related to wrinkle reduction or those containing active ingredients that stimulate collagen or elastin production, including topical and oral products used within the past three months (e.g., coenzyme Q10, marine extracts, pine bark extract, glutathione, and vitamin C)
• Participation in any other volunteer study or program within the past three months
• Use of the following medications within the past three months: contraceptives, phenytoin, hydantoin, levodopa, chloroquine, cancer chemotherapy drugs, or medications containing heavy metals
• History of receiving dermatological or cosmetic procedures such as IPL (Intense Pulse Light) laser, phonophoresis, iontophoresis, laser treatments, Botox injections, fillers, or stem cell injections
• Volunteers who exhibit sensitivity or irritation to the test products used in the study