Table 3

Mean serum hormone concentrations (nmol/liter) in 292 women meat-eaters, vegetarians, and vegansa

Back-transformed means with 95% CIs (in parentheses).

Hormone (nmol/liter)Meat-eaters (n = 99)Vegetarians (n = 101)Vegans (n = 92)Test of heterogeneity
IGF-I30.9 (29.3–32.7)31.2 (29.5–32.9)27.0 (25.5–28.6)0.0006
IGFBP-10.91 (0.78–1.07)0.90 (0.77–1.06)1.28 (1.08–1.51)0.005
IGFBP-211.2 (9.79–12.7)13.2 (11.7–14.9)15.8 (14.0–17.6)0.0008
IGFBP-3148 (142–154)140 (135–146)144 (138–150)0.171
IGF-I:IGFBP-3 ratio0.21 (0.20–0.22)0.22 (0.21–0.23)0.19 (0.18–0.20)0.0001
C-peptide0.83 (0.76–0.90)0.87 (0.80–0.95)0.76 (0.69–0.83)0.236
SHBG51.7 (46.6–57.4)50.9 (45.9–56.5)54.7 (49.1–61.0)0.624
  • a Values are adjusted for age (10 categories), assay batch (4 categories), time of day at venipuncture (4 categories), time since last meal at venipuncture (4 categories), and time between venipuncture and blood processing (4 categories). Insufficient serum led to IGF-I and IGFBP-3 measurement being unavailable in 1 subject and SHBG in 2 subjects.