No! However, for accurate health measurements, we advise you to wear tight-fit clothes (For example, compression clothing and sports bra) and be consistent with your scans over time to avoid altering our data.
On the other hand, you can also take non-fitness scans. During these ‘fun scans’ you can wear whatever you want and also stand in any position you feel like so. Actually, some of our alpha users enjoyed using their ShapeScans™ to try on different clothes and visualize them.