The use of dried blood spots (DBS) has many advantages over traditional plasma and serum samples such as the smaller blood volume required, storage at room temperature, and ability for sampling in remote locations. However, understanding the robustness of different analytes in DBS samples is essential, especially in older samples collected for longitudinal studies. Here we analyzed the stability of polar metabolites and lipids in DBS samples collected in 2000-2001 and stored at room temperature. The identified and statistically significant molecules were then compared to matched serum samples stored at −80°C to determine if the DBS samples could be effectively used in a longitudinal study following metabolic disease. Four hundred polar metabolites and lipids were identified in the serum and DBS samples using gas chromatograph-mass spectrometry (GC-MS), liquid chromatography-MS (LC-MS) and LC-ion mobility spectrometry-MS (LC-IMS-MS). The identified polar metabolites overlapped well between the sample types, though only one statistically significant metabolite was conserved in a case-control study of older diabetic males with high body mass indices, triacylglycerides and glucose levels, and low amounts of high density lipoproteins and non-diabetic patients with normal levels, indicating that degradation in the DBS samples affects quantitation. Differences in the lipid identifications indicated that some oxidation occurs in the DBS samples. However, thirty-six statistically significant lipids correlated in both sample types indicating that the lipids did not degrade as much as the polar metabolites in the DBS samples and quantitation was still possible.