If you have yellow urine during weight loss, it is recommended to go to the hospital for relevant examinations to clarify the possible causes.1. If you are using special weight loss drugs, it may lead to yellow urine color. It is recommended to stop the intake of the relevant weight loss drugs, and then drink more water as appropriate, and observe whether the urine is still yellow. If necessary, you need to carry out a laboratory analysis of the urine to clarify whether you have a related disease. 2, when the weight loss or long-term fasting, resulting in metabolic disorders in the body, urine concentration or urine metabolism abnormalities caused by the yellow color. At this time, you need to go to the hospital for routine urine examination to find out whether there is an increase in the level of urinary bilirubin or an increase in the level of urobilinogen. Liver function tests and serum proteology tests are also needed to further assess whether there is a generalized nutritional metabolic disorder, etc., and according to the results of the tests, symptomatic treatment will be provided.