It is unclear whether mandibular implant overdentures improve the nutritional state of edentulous patients better than conventional dentures. In a randomized clinical trial, we tested for post-treatment differences in nutritional status between patients with mandibular two-implant retained overdentures and those with conventional complete dentures. Edentulous subjects (ages 65-75 yrs) received two-implant mandibular overdentures (IOD, n = 30) or conventional dentures (CD, n = 30). Measures of nutritional state were gathered before and 6 mos after treatment. Significant improvements in anthropometric parameters were detected in the IOD but not in the CD group, for percent body fat (p = 0.011) and skin-fold thickness at the biceps, subscapularis, and abdomen (p < 0.05), with significant decreases in waist circumference (p < 0.0001) and waist-hip ratio (p = 0.001). Significant increases were seen in concentrations of serum albumin (p = 0.015), hemoglobin (p = 0.01), and B12 (p = 0.01). No significant between-group differences were found. These results suggest that low-cost IOD treatment may improve the nutritional state of edentulous people.