The blood tests with real evidence for skin health are the ones that measure the biological drivers of how skin ages — not general disease markers.
Standard blood work is designed to catch disease. Its reference ranges are wide by design. A vitamin D of 32 is normal. An HbA1c of 5.9 is normal. A ferritin of 25 is normal. None of those numbers is medically alarming. All of them can be quietly aging your skin.
The nine biomarkers with the strongest peer-reviewed evidence for skin aging in women:
- hs-CRP — high-sensitivity C-reactive protein. A marker of chronic inflammation, which drives matrix metalloproteinases that break down collagen and elastin (Fisher et al., 2002).
- HbA1c — 90-day glucose average, which reflects how much glycation is quietly cross-linking collagen (Monnier, 1990).
- Fasting glucose & insulin — earlier metabolic strain signals than HbA1c alone.
- Estradiol — the primary estrogen; connected to dermal collagen thickness (Brincat, 1983; Verdier-Sévrain, 2006).
- Vitamin D (25-OH) — supports DNA repair after UV exposure and skin immune function.
- Vitamin B12, zinc, ferritin — nutrient status connected to cellular turnover, wound healing, and skin structural maintenance.
- Omega-3 Index — the fatty-acid composition of red blood cell membranes; low levels correlate with impaired skin barrier function (Pilkington, 2011).
You can order these tests individually through a functional medicine physician. What you won't get from any standard lab is a translation — a report that scores those nine numbers against skin-optimized reference ranges (tighter than clinical normal) and produces a personalized narrative on what your specific pattern means for your skin. That translation is the JenSkin panel.