Yes / Background: Multiple biomarkers have been associated with hair loss in women, but studies showed inconsistent results. Objective: We investigated the association between markers of cardiovascular disease risk (e.g., serum lipid levels and hypertension) and aging (e.g., 25-hydroxyvitamin D and insulin-like growth factor) with hair loss in a population of middle-aged women. Methods: In a random subgroup of 323 middle-aged women (mean age: 61.5 years) from the Leiden Longevity Study, hair loss was graded by three assessors using the Sinclair scale; women with a mean score higher than 1.5 were classified as cases with hair loss. Results: Every standard deviation increase in HDL cholesterol was associated with a 0.65 times lower risk (95% confidence interval [CI]: 0.46–0.91) of hair loss; for IGF-1 the risk was 0.68 times lower (95% CI: 0.48–0.97) per standard deviation increase, independent of the other studied variables. Women with both IGF-1 and HDL cholesterol levels below the median of the study population had a 3.47 times higher risk (95% CI: 1.30–9.25) of having hair loss. Limitations: The observational setting limits causal inference of the findings. Conclusion: Low HDL cholesterol and IGF-1 were associated with a higher risk of hair loss in women. / This study was funded by the Innovation Oriented Research Program on Genomics (SenterNovem; IGE01014 and IGE5007), the Centre for Medical Systems Biology (CMSB), the Netherlands Genomics Initiative/Netherlands Organization for Scientific Research (05040202 and 050-060-810, NCHA), Unilever PLC and the European Union-funded Network of Excellence Lifespan (FP6 036894).