A weakly positive urine ketone body is generally harmless and can be seen as a result of starvation ketone bodies that occur after fasting for a test. Another condition is diabetes mellitus that may be combined with a less severe degree of diabetes mellitus, which is caused by fat mobilization for energy when glucose cannot function. As long as you drink a lot of water and urinate, you can turn urine ketone bodies to negative after urinating them out of your body, so overall, there is no risk or danger of weakly positive urine ketone bodies.