Skin carotenoid levels and immune aging

Carotenoids in the Skin and Immune Aging: a Pilot Observational Study

Observational Stanford University · NCT07221643

This project will see if skin carotenoid levels are linked to immune health in healthy adults aged 18–30 and 65 and older.

Quick facts

Study typeObservational
Enrollment40 (estimated)
Ages18 Years and up
SexAll
SponsorStanford University Academic / other
Drugs / interventionsmethotrexate, prednisone
Locations1 site (Redwood City, California)
Trial IDNCT07221643 on ClinicalTrials.gov

What this trial studies

This observational study will measure skin carotenoid content noninvasively and compare those levels with a range of immune-related health parameters in two age groups (18–30 and 65+). Eligible participants are healthy adults of all Fitzpatrick skin types who are not taking immune-altering prescription medications and do not have interfering skin disease on the upper extremity. The protocol excludes pregnant or breastfeeding people and those with uncontrolled medical conditions. Participants will attend the Stanford Health General Dermatology Clinic in Redwood City for measurements and specimen collection as specified by the study team.

Who should consider this trial

Good fit: Healthy adults aged 18–30 or 65 and older without uncontrolled medical conditions, not pregnant or breastfeeding, and not using immune-modifying prescription medications are ideal candidates.

Not a fit: People with active skin disease on the upper extremity, recent use of immune-suppressing medications, uncontrolled medical conditions, or who are pregnant/breastfeeding are unlikely to qualify or gain direct benefit from participation.

Why it matters

Potential benefit: If successful, the work could identify a simple, noninvasive skin marker that reflects immune aging and help target monitoring or preventive efforts.

How similar studies have performed: Previous research has used noninvasive skin carotenoid measurements to reflect dietary antioxidant status, but applying those measures specifically to track immune aging is relatively novel and not yet proven.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Willing and able to provide written informed consent
* Age 18-30 years OR 65 years and older
* Healthy individuals without uncontrolled medical conditions (over the counter inhaled and topical steroids allowed)
* Fiitzpatrick I-VI (all skin types)

Exclusion Criteria:

* Pregnant or breastfeeding
* uncontrolled medical conditions
* Skin conditions on the upper extremity that would interfere with skin measurements of carotenoid levels such as active atopic dermatitis or psoriasis
* Concurrent use of medications that affect the immune system, within 4 weeks of enrollment (eg. prednisone, biologics, methotrexate, rapamycin, prescription topical steroids, prescription inhaled steroids, others)
* Unable to follow study protocol

Where this trial is running

Redwood City, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions No ConditionSkin Carotenoids and Immune-aging
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.