Overt hypothyroidism and subclinical hypothyroidism are thought to be associated with atherosclerosis and a chronic ischemic process. Ischemic modified albumin (IMA) is a novel marker of ischemia. We examined serum IMA levels in patients with subclinical and overt hypothyroidism. We recruited patients who presented to our clinic for thyroid disease control. We compared demographic data, fasting blood sugar, serum lipid levels, and the prevalence of metabolic syndrome by the presence of overt, subclinical, and no hypothyroidism. Cobalt binding to albumin capacity was analyzed using a rapid colorimetric technique and compared among the groups. We assessed 11 men and 74 women with a mean age of 39.9 +/- 12 years. Of these, 48 (56.5 %) were euthyroid, 24 (28.2 %) had subclinical hypothyroidism, and 13 (15.3 %) had overt hypothyroidism. The groups did not differ significantly in terms of age; body mass index; waist circumference; systolic and diastolic blood pressures; levels of fasting and nonfasting blood sugar, high- and low-density lipoproteins, and triglycerides; and the presence of metabolic syndrome. Mean serum IMA level also did not differ significantly among the groups: 0.20 +/- 0.08 absorbance units (ABSU) in the euthyroid participants, 0.18 +/- 0.08 ABSU in those with subclinical hypothyroidism, and 0.20 +/- 0.09 ABSU in those with overt hypothyroidism (P = 0.754). Mean IMA values did not differ significantly by sex, cigarette use, the presence of metabolic syndrome, or the presence of thyroid autoantibodies. Serum IMA levels did not differ among patients with overt or subclinical hypothyroidism in this case-control study.