Why Does My Kid Smell Like Onions?!

“Oh how sweet,” you think, as the onion smell hits your nose upon arriving home. “Someone’s started making dinner!” But, your excitement soon morphs into what can only be described as a creeping sense of horror, as you enter the kitchen and notice the distinct absence of a stir-fry supper sizzling away on the stove top.

That smell is, in fact, coming from your odorous child who’s not long arrived back from sports practice. Panic sets in, and a million questions start racing through your mind. How? When? Why? Why me?

Let’s dig in and see if we can get you some answers, and some help, while you pull up Uber Eats.

Bacteria

As we’ve discussed in some previous posts (like this one), B.O. is caused by bacteria on our skin eating our sweat and farting out stinky gases. But, there are multiple different types of bacteria that live on our skin and create these odors. And, just as humans produce varying odor profiles with their flatulence, bacteria do, too!

Therefore, the specific types of bacteria that are most prominent on your kid’s skin can influence their individual smell. And some types of bacteria are just more prone to onion-y smell production than others. This is one you can’t do much about (besides keeping the bacteria at bay with regular bathing, of course), but what other causes are there?

Genetics

Each person’s unique body chemistry — influenced by our genes — also plays a role in how our B.O. smells. Some people’s B.O. smells sweet (lucky devils), others sour, others musty, others spicy (think cumin, not hot peppers), and others, well, onion-y. It could be the case that your child is just genetically pre-disposed to having body odor that smells like French onion soup. Do any of the adults in your family smell that way?

If not, or if your kid has rather suddenly developed their onion-y aroma, then there’s probably something else going on. Keep reading.

Hormones

During periods of hormonal fluctuation, such as puberty, our body chemistry is changing a lot. And those chemical changes get reflected in our sweat, which in turn influences the aroma of the bacteria farts. It’s a bit of a chemical chain reaction, if you will.

So, if your child is currently going through puberty, or even approaching puberty age, then their body’s natural hormonal changes could be the culprit causing the onion smell. This is often the case if the smell has come about very suddenly. But, there is one more factor to consider…

Diet

Just like our genes and hormones can influence the way our sweat smells and tastes to bacteria, so, too, can our diet! This can happen when our diet contains a lot of foods that are particularly high in sulfur — such as eggs, garlic, cabbage, dairy, and, yes, onions. As these foods are broken down, excess sulfur compounds get excreted through our sweat, which in turn makes the resulting bacterial gases smell more sulfurous. And as you may know, sulfur is often described as smelling egg-y or onion-y.

If you suspect this bodily process could be what’s making your child stinky, try pinpointing the most sulfur-heavy foods in their diet and cutting back on those items to see if it makes a difference.

What to do about it?

If your child’s practicing good hygiene, and the onion aroma doesn’t appear to be caused by their diet, then there’s probably little you can do to make it magically disappear. Except, of course, getting them a good kid-friendly deodorant.

Unlike antiperspirant that blocks up sweat glands with aluminum, deodorant works by making your child’s armpits (or other stinky areas) a rather inhospitable and uninviting place for bacteria to hang out. No bacteria = no bacteria farts = no odor. Magic!

Since your kid’s armpit skin is quite sensitive, though, you want to make sure you get them a gentle deodorant that won’t cause any rashes or discomfort. Like Kobi’s Natural Sport Deodorant. It’s safe and effective for kids of all ages and lifestyles, and even strong enough to keep extra-sporty kids smelling fresh through practices and games. So they won’t trick you into thinking dinner’s nearly ready.