The correct interpretation of the sentence in the context of the witch trial is "Some people in the village were so poorly fed, they had little flesh on their bodies."
The line discusses the condition of a person who is bound and placed in water, suggesting that a lack of body mass (like being "mere skin and bones") could affect their ability to float or swim. This reflects the broader themes of the witch trials, where the physical condition and societal perceptions of individuals could influence the trial outcomes.