Beetroot juice has no harmful side effects and the only side effect it has will be the change in color of your urine. This is known as Beeturia, and what happens is that your urine and stools will have a pinkish tinge. It can scare some people who are unaware of it. But this happens only when large amounts of beetroot juice are consumed. Another side effect of beetroots is that it is high in oxalate and this can harm those with kidney stones. Another rare side effect of beetroot juice is hives, chills and fever. Also beetroot juice when consumed by itself can cause vocal problems, so it's advisable to drink it with other vegetable juices.