Background: Adults with a high body mass index (BMI) have an increased risk of developing asthma. To explore the impact of increased lipids on the presence of asthma, this study investigated the relationship between lipid levels and inflammatory markers in patients with asthma and controls with obesity. Objective: We hypothesized that higher lipid levels are more prevalent in patients with obesity and asthma. Methods: In this explorative cohort study, 96 patients with asthma and 45 controls were included. All the patients participated in one of three asthma studies; two of these studies included only patients with obesity. An asthma diagnosis was defined by the presence of typical clinical symptoms, reversible airway obstruction (+12% improvement in forced expiratory volume in the first second of expiration after bronchodilator), or bronchial hyperreactivity (Histamine PC20 < 8 mg/mL), or a fractional exhaled nitric oxide of > 50 ppb. We compared lipid levels and neutrophils and eosinophils in patients with asthma and the controls with a wide BMI range (17.8-63.8 kg/m²). Multivariable logistic regression was used to analyze the data. Results: Serum triglycerides were statistically significantly higher in patients with obesity and asthma adjusted for BMI, blood eosinophils, and statin use (odds ratio [OR] 2.56 [95% confidence interval, 1.34-4.88]; p = 0.004). Inclusion or exclusion of those who used long-acting β2-agonists and inhaled corticosteroids led to comparable adjusted ORs for blood triglyceride and blood eosinophils levels. Conclusion: Elevated serum triglycerides were associated with the presence of asthma in patients with obesity. This indicated that elevated triglycerides might be a yet unrecognized trait that contributed to the development of asthma. The precise cause and effect of these high triglyceride levels in the patients with asthma and with obesity were not determined in this study.Clinical trial Trial registration NCT03278561, <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.clinicaltrials.gov">www.clinicaltrials.gov</ext-link>; NL4262, NL3056, trialregister.nl.