This is a randomized, double-blind, placebo-controlled clinical trial exploring the effects of a 12-week dietary supplement regimen on skin condition and perceived overall health status.

The study will involve 120 healthy Chinese adults aged 18 and above with low daily fruit and vegetable intake. Participants will be randomly assigned to one of two groups: one group will take a combination of Nu Skin's Vitamin C & Green Tea Capsules and Multivitamin & Mineral Capsules, while the other group will take a matching placebo.

The primary goal is to assess if the supplement combination improves skin health after 12 weeks, measured through specialized facial imaging (assessing spots, redness, evenness) and probe measurements (assessing elasticity, moisture, gloss). Secondary goals include evaluating changes in participants' self-perceived health status (via quality of life, fatigue, and digestive health questionnaires), psychological resilience, memory, and exploring a new method for measuring skin carotenoid levels.

This study is not intended to verify the approved health functions of the products but to explore the potential combined effects of antioxidant and nutritional supplementation on skin and general well-being.

Inclusion Criteria:

1. Chinese adults of Asian descent aged 18 and above;
2. Daily fruit and vegetable intake < 240g (calculated based on the fruit and vegetable section of the food frequency questionnaire);
3. S3 measurement index < 30000;
4. Participants must possess basic Chinese reading comprehension and expression skills, and be able to independently complete questionnaire surveys;
5. Voluntary participation in the test and signing of the informed consent form;
6. Willingness to comply with all evaluation requirements.

Exclusion Criteria:

1. Presence of open facial skin lesions, clearly visible scars, acne marks, etc.;
2. Skin lesions, scars, or significant pigmentation on the hand measurement area;
3. Symptoms of skin disease on the face or hand measurement areas;
4. Having undergone medical aesthetic procedures within the last 6 months;
5. Participation in other clinical trials involving product use within the last 3 months;
6. Use of health supplements or nutritional supplements (e.g., vitamins, minerals) within the last 1 month;
7. Currently planning for pregnancy, pregnant, or lactating;
8. Presence of any disease under current treatment;
9. Any other health issues or chronic diseases that affect behavioral or cognitive abilities;
10. Other iatrogenic reasons identified by experts or professionals that may affect the evaluation results.

The S3 instrument refers to a Raman spectroscopy-based biophotonic scanner. The threshold for the S3 screening value is based on previously published literature, which indicated that participants with a daily fruit and vegetable intake of less than 240g had an average Raman spectroscopy biophotonic scanner score below 25,000. However, considering practical recruitment challenges, the inclusion criterion was set at < 30,000. The S3 device measures the Skin Carotenoid Index, a non-invasive biomarker reflecting skin carotenoid levels.