Aging is characterized by deleterious immune and metabolic changes, but the onset of these changes is unknown. We measured immune and metabolic biomarkers in adults beginning at age 30. To our knowledge, this is the first study to evaluate these biomarkers in adults aged 30 to over 80. Biomarkers were quantified in 961 adults. Tumor necrosis factor alpha (TNF-α), tumor necrosis factor receptor I (TNFR-I), tumor necrosis factor receptor II (TNFR-II), interleukin (IL)-2, IL-6, VCAM-I, D-Dimer, G-CSF, regulated on activation, normal T cell expressed and secreted (RANTES), matrix metalloproteinase-3 (MMP-3), adiponectin, and paraoxonase activity were measured by ELISA. Acylcarnitines and amino acids (AAs) were measured by mass spectrometry and reduced to a single factor using principal components analysis (PCA). Glycine was analyzed separately. The relationship between age and biomarkers was analyzed by linear regression with sex, race, and body mass index (BMI) as covariates. Age was positively correlated with TNF-α, TNFR-I, TNFR-II, IL-6, IL-2, VCAM-1, D-Dimer, MMP-3, adiponectin, acylcarnitines, and AAs. Age was negative correlated with G-CSF, RANTES, and paraoxonase activity. BMI was significant for all biomarkers except IL-2, VCAM-1, RANTES, paraoxonase activity, and the AA factor. Excluding MMP-3, greater BMI was associated with potentially adverse changes in biomarker concentrations. Age-related changes in immune and metabolic biomarkers, known to be associated with poor outcomes in older adults, begin as early as the thirties.