7 things the colour of your pee can tell you

You can learn a lot about what's going on inside your body by examining what comes out of it.

In fact, it's become pretty standard advice to keep an eye on what you leave behind when you pee, and to aim for a light lemonade colour as a sign of optimal hydration.

The problem, other than the fact that you have to look into the toilet bowl, is that taking a glance at the colour of your pee isn't always as accurate at predicting true dehydration as, say, a blood test, according to research in the American Journal of Clinical Nutrition.

The study examined hydration tests among older adults and found that urine colour can be changed by too many other things to accurately predict hydration.

The yellow colour of urine comes from a chemical byproduct that results when your kidneys do their job of processing waste, explains Koushik Shaw, M.D., a urologist and founder of Austin Urology Institute in Texas.

The more dehydrated you are, the more concentrated the urine becomes and the darker the colour gets.

"A pale yellow colour reflects a good balance between over- and underhydration," he says.

There are times, though, when you don't see pale yellow in the bowl, and dehydration has nothing to do with it. Believe it or not, pee can come in a whole rainbow of colors.

Here's what you should know when your pee doesn't look like lemonade.

Bottom line? You'd rather ask your doctor about it when it's not a big deal than when it is.

"Healthy urine can range from clear to dark yellow, but if it's any other colour in the rainbow and hydration or diet doesn't fix it," Shaw says, "it's best to get it checked."

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