Taste assessment was tested in 20 obese and 20 normal-weight in-patients using watery solutions of saccharose and three synthetic sweeteners. Each patient was asked to assess ten different taste qualities of each solution on a point scale. There were highly significant differences between the two groups of subjects. The difference was especially marked for the categories "synthetic - natural", "unpleasant - very tasty", and "changeable - stable in times". These findings suggest changes in physical or central taste sensation in obese persons. This view is supported by their decreased ability to differentiate between saccharose and any sweetener. The results further support substituting sweetening agents for sugar in reducing diets.