Why Does Asparagus Make Your Urine Smell?

Why does asparagus make your urine smell?

Why Does Asparagus Make Your Urine Smell?

It’s a widely known fact that eating asparagus can give your urine a stronger smell. But why is that? And are there other foods that have the same effect? Today we’re exploring this phenomenon to figure it out.

Why does asparagus make your urine smell?

There are two root causes for the strong, unpleasant-smelling urine that can result from eating asparagus:

Asparagusic acid. Asparagus contains a unique chemical called (for obvious reasons) asparagusic acid. This chemical is so unusual that we haven’t yet detected it in any other foods. When we digest this acid, our body breaks it down into a number of smaller compounds, many of which contain sulfur. As we know from rotten eggs and skunk spray, sulfur compounds have a strong, unpleasant smell. The sulfur compounds that we create from digesting asparagus can be created very quickly, within less than a half hour of eating the vegetable, and they are volatile. Their volatility means that they are able to “boil”, so to speak, at room temperature, and convert from a liquid to a gas when you urinate. This volatility means the gas evaporates and lifts into the air, carrying the aroma from your toilet bowl to your nose.

Genetics. It has long been known that some people simply don’t have this odor after eating asparagus. An estimated 20-40% of the population doesn’t experience this phenomenon. But scientists have been divided on whether the difference is due to the fact that some people simply don’t produce these compounds during digestion, or whether they produce the compounds, but can’t smell them. Believe it or not, there have been a variety of scientific studies on the issue, and current consensus appears to be that everyone produces these sulfur compounds when they digest asparagus, but some people have a genetic difference in their olfactory receptors, and can’t smell the resulting odor.

What this means is that, even if you can’t smell the strong odor resulting from eating asparagus, there is a high probability that other people can.

Other foods that can make your urine smell

While asparagus has that distinctive asparagusic acid, other foods that produce sulfur compounds during digestion can also contribute to a strong smell when you urinate. Broccoli, cauliflower, Brussels sprouts, and garlic all contain methyl-mercaptan, a chemical that produces organic sulfur as it is processed through your kidneys.

When is urine smell a problem?

If your urine has a strong, unpleasant smell, and you haven’t recently eaten any of these problematic vegetables, it may be a cause for concern. While it is normal for urine to be darker in color and have a stronger smell first thing in the morning due to being more concentrated, noticeable changes in the way your urine looks or smells can be a reason to worry. If you notice a strong, unpleasant smell in your urine, or a strong sweet smell, it may be a sign of a medical condition.

How to keep your urine smelling fresh

Well, your urine may never smell like a rose garden, but there are a few ways you can reduce the unpleasant odor associated with urine and boost your health at the same time.

Stay away from sulfur-containing foods. While asparagus, broccoli, and garlic are all good for you, and should not be avoided altogether, you may want to steer clear of them during times when you want to avoid excessive odor in your urine.

Avoid coffee and alcohol. Coffee and alcohol can both have a diuretic effect, which may make you urinate too much and cause dehydration. Dehydration concentrates urine and makes it smell more strongly.

Always urinate right after sex. Urinating after sex can help prevent urinary tract infections, which keeps you and your urine healthy.

Drink plenty of water. The best thing you can do for your kidneys and your urine is to drink lots of water. Drinking plenty of water dilutes your urine, making it lighter in color and reducing any associated odor. It’s also good for every other part of your body, so make sure you stay hydrated.

While asparagus is the only food with that distinctive chemical that affects your urine’s smell, there are a lot of foods and behaviors that can impact the odor of your urine. Remember that, even if you can’t smell it, other people can. Stay hydrated and use caution with sulfurous foods.