I have lupus (nephritis-kidney), is there any harm in eating beets?

Depends. Lupus nephritis can lead to chronic kidney disease (an elevated creatinine on your bloodtest). If you have ckd, then beets are bad for you. Beets have a high amount of potassium so people with ckd can not eliminate that excess potassium. High potassium in the body can lead to cardiac issues. Therefore avoid beets if your lupus nephritis caused chronic kidney disease.