3 myths about keeping ants out of your house

 It’s that time again: soon our gardens will be full of flowers and our kitchens full of ants. Only one of these developments is welcome.

Ants are, in some ways, the dominant creatures on the planet. There are, by one estimate, 20 quadrillion ants on planet earth. That’s 12 megatons of biomass, weighing more than every wild bird and mammal combined. So it probably shouldn’t be surprising when ants show up in our homes—but that doesn’t make it any more pleasant.

And we have all kinds of weird ideas about ants in our home. Some people think an ant showing up means your house is dirty (not necessarily), while others think it’s a good idea to break out the bug spray (it’s not). Let’s explore a few common ant myths, and see what research has to say about them. 

Ants don’t (necessarily) mean your house is dirty.

The most common advice, when it comes to ants, is keeping things clean. And it’s true that leaving food out will attract ants, but even the cleanest houses get ants sometimes. 

“Finding a few ants in your home doesn’t mean your house is dirty.” Tanya Latty, a professor at the University of Sydney, wrote in an article for The Conversation. “We simply live on a planet that is absolutely teeming with ants.” 

This isn’t to say that cleanliness isn’t useful when it comes to fighting infestations—,just that it’s not a guarantee. So yes, it’s a good idea to store food in airtight containers, regularly clean in hard-to-reach places like under the fridge and stove, and generally do everything you can to make sure there’s not a lot of ant food available in your house, according to Latty. But even the slightest amount of food is going to attract ants: “Ants have tiny stomachs, so even small crumbs or the residue from spilled sugary drinks can be enough to entice them back,” Latty wrote.

And food isn’t the only reason ants might find their way into your house. They may be looking for water, especially in the summer, meaning even the smallest plumbing leaks could attract them. Or, if it’s been raining a lot outside, they may come into your house in search of somewhere dry to live. Basically, cleanliness is only one factor when it comes to ants (if an important one). Another thing you can do to decrease the likelihood of seeing an ant, according to Latty, is sealing any small cracks or other potential entrances used by ants. 

Bug spray isn’t the best idea

You might, after seeing a line of ants in your house, reach for a can of bug spray. And it will kill the ants you can see, granted, but the ants you can see aren’t the problem. 

“Ant poison may make you feel like you’re accomplishing something, but you’re not,” Michael Hansen, PhD, a biologist and ecologist, wrote in an article published by Consumer Reports. “Unless you solve the problem of what’s attracting them to your house—and how they’re getting in—you should remember that there are thousands of ants in every colony, and you’ll just keep seeing them.”

Not only does bug spray not work, according to Hansen, it also has a bunch of downsides. “Some of these sprays contain chemicals that are endocrine-disrupting compounds, which can alter our hormones,” said Hansen. “Similar compounds have been linked to neurobehavioral effects in children, including reduced IQ and increased rates of ADHD, even at the low levels you’d be exposed to when spraying your house.”

The article suggests instead relying on purpose-made ant baits, which are readily available. Unlike spray, which only affects the ants you can see, bait is designed to be brought back to colonies by worker ants, and then eaten by the rest of the colony. This kills the colony at the source. Keep in mind that different species of ants are attracted to different kinds of bait, so you may need to try a few different ones. 

Pepper and cinnamon can deter ants, but not for long

So bug sprays are out, but what about natural remedies? The internet is full of natural alternatives to bug spray—cinnamon or pepper, for example. The idea is that you can disrupt a trail of ants by putting something that smells strongly in their way. And there is research that suggests this works—a study by Universiti Teknologi MARA researchers in Malaysia suggests that ethanol-based extracts with chilli pepper, black pepper, and cinnamon all deter ants. 

So you could, in theory, use any of these or other remedies to break up the chemical trail ants are using to find their way into your house, without having to worry about the health concerns associated with bug spray. You might even notice they work for a while. The problem is, if ants are determined to get into your house, they will eventually find another way in. Research from Stanford University published in American Nationalist suggests that ant colonies are extremely good at finding workarounds to broken trails, meaning it’s only a short-term solution. 

Again, you’re probably better off sealing any entrances ants may be using, ensuring there’s not food or water laying around, and setting out ant bait. 

 

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