Human adenovirus-36 (Ad-36) increases adiposity in chickens, mice, and non-human primates, and is associated with human obesity. Ad-36 paradoxically reduces serum cholesterol and triglycerides in animal models. Ad-36 increases adipocyte differentiation and triglycerides accumulation in 3T3-L1 cells in vitro. This study evaluated whether three other human adenoviruses increase adiposity in chickens, and in 3T3-L1 cells in vitro. We inoculated chickens with human Ad-2, Ad-31, Ad-37 or media at age 3 weeks. Food intake and weights were recorded for 3.5 weeks, then chickens were sacrificed and visceral fat, body composition, serum lipids, and viral antibody status determined. Visceral fat and total body fat were significantly elevated (p<0.001) in the Ad-37 group compared to all other groups. Final body weights were higher in chickens inoculated with Ad-37 compared to Ad-2, but not significantly higher than control or Ad-31 groups. Food intake did not differ among groups. Serum cholesterol was elevated in Ad-37 chickens compared to control (p<0.01), but was not affected by other viruses. Triglycerides were reduced in Ad-37 chickens (p<0.0001), but were not affected by other viruses. In 3T3-L1 cells in vitro, Ad-31, Ad-36, and Ad-37, but not Ad-2, increased adipocyte differentiation and triglycerides accumulation. In summary, Ad-37 is another human adenovirus that increases adiposity and reduces serum triglycerides in an animal model. However, the response of serum cholesterol is opposite that of Ad-36. Evaluation of other human adenoviruses to determine their effects on adiposity and serum lipids is warranted, but in vitro assays may not be definitive for this purpose.