Is having urine the color of Mountain Dew normal?

A doctor who advises several Trump cabinet members on their diets rhapsodized this summer about having urine the color of Mountain Dew, thanks to a diet consisting entirely of meat and fermented foods.

What you consume does determine what you see in the toilet. But should urine be neon yellow – or some other hue? Here’s what you need to know.

What color should urine be?

Urine is normally a shade of yellow owing to a pigment called urobilin, which your gut bacteria produce. The more diluted it is by extra fluid intake, the lighter its shade – so urine is typically darker in the morning or when you’re dehydrated.

You may have seen charts that indicate what color and shade urine “should” be, but “they are considered imprecise” and experts don’t rely on them for serious purposes such as managing kidney disease, says Suzanne Watnick, a nephrologist at the University of Washington. Urine’s darkness or lightness loosely corresponds with hydration status, but for most people, it’s best to rely on your sense of thirst rather than what’s in the toilet to determine when to drink water.

That said, in people who need to stay highly hydrated, urine shade can be a helpful hydration indicator. For example, people prone to kidney stones should aim for very pale urine, Watnick says.

What factors can affect your urine’s appearance?

Your kidneys constantly filter blood to remove excess water and waste products, which trickle down to the bladder to get peed out as urine. These organs’ goal is to ensure your blood consistently has exactly the right balance of fluid, minerals, salts and acid.

“Your kidneys are really smart,” says Sharon Moe, a nephrologist at Indiana University School of Medicine. As long as they’re healthy, you can’t really override their settings. For instance, if you consume more water-soluble nutrients than you need, anything “extra” ends up in the toilet. This includes the by-products your body makes when it breaks down food and medicines, as well as the majority of any vitamins and supplements you might be taking.

Some of these compounds won’t visibly change urine – for instance, digesting a lot of beef is likely to turn urine more acidic but not change its color, says Watnick. But some can change the color of urine or make it exceptionally bright. B vitamins (like riboflavin) can turn it fluorescent yellow, rhubarb a reddish-brown, and beets a festive pink.

Anything but the usual yellow – including Mountain-Dew-adjacent hues – may signal your body is consuming something it can’t use. “If you get super fluorescent or super red, you’re eating too much of something or taking too many supplements,” says Moe.

What should you do if your urine changes unexpectedly?

For most healthy people, urine color changes are rarely an emergency. Notable exceptions include people with kidney disease, or if the color change is accompanied by other concerning symptoms like new pain, a new rash or severe leg swelling. These types of changes might signify a medical problem – get it checked out.

Otherwise, to troubleshoot a strange new urine hue, first stop any supplements you’re taking, says Moe. If it doesn’t go back to normal, cut out brightly colored foods next.

Additionally, look over your medication list. If you recently started a new drug, ask your clinician whether it could cause urine color changes. But don’t stop taking any prescribed medicines before that conversation, as urinary changes are an expected and harmless side-effect of some drugs.

What urine changes can signify health problems?

If your urine is red or brown, you haven’t had any red flag symptoms, and the color persists after you’ve ruled out any recent dietary or medication changes, get checked out.

Bleeding in the kidneys, the bladder or the urinary tract can also turn it red or brown, and your clinician can assess that with a simple urine test. (In people who menstruate, it can occasionally be challenging to determine where blood in the toilet is coming from. Talk to your clinician if you’re not sure.)

Foamy urine can mean protein is leaking from your kidneys – a few bubbles aren’t worrying, but you should be concerned if you see anything that looks “like a beer head in the toilet”, says Moe.

Odor, frequency and transparency are also important. A sweet or foul smell, peeing much more or less than usual, and cloudy urine are all reasons to get checked.

Although urine changes can occasionally herald kidney problems, most kidney disease is invisible; 37 million US adults have chronic kidney disease, but only one in 10 of them is aware. Moe says the best prevention is keeping your blood pressure in a healthy range and eating lots of fruits and vegetables, with meat in moderation. “The carnivore diet is not a healthy diet,” she says.