Welcome back to Just Curious, Strong Women’s weekly series exploring all the random health and fitness questions you’ve always wondered about but never got the answers to.

This week, we’re exploring whether the plants in our homes can really purify the air, and what other steps we can take to minimise indoor air pollution. 

There’s something about having a few houseplants around that really brings a home to life, which is why even the least green-fingered among us will be keen to have a handful knocking about.

As well as looking great, having plants in the home has been shown to reduce stress, improve mood and even boost productivity – making them an attractive prospect for anyone looking to enhance their wellbeing and upgrade their home environment.  

And, of course, that’s not forgetting claims that plants can purify the air. Visit any online plant shop and they’ll have a section dedicated to air-purifying plants, usually featuring a selection of aloe vera, snake plants and peace lilies.

The question is: can having plants in the home really make the air cleaner and better for us to breathe? And if so, how many houseplants do you need to have an impact? We asked the experts to explain all.  

While houseplants can purify the air around them to an extent, the impact may not be as big as we’re led to believe. Much of the hype surrounding the ability of plants to keep our homes pollution-free is based on the findings of NASA’s 1989 clean air study, which found that numerous plants – such as parlour palms, corn plants and devil’s ivy – could absorb pollutants.

However, this study was limited in its applications to day-to-day life. For one thing, the aim of the study was to find ways to purify the air in small, unventilated spaces (like those found in space).

Kelly Dyer, a plant doctor and horticultural lead for Patch Plants, explains how plants absorb toxins from their environment – and why their impact, while measurable, may be limited.

“In a nutshell, air purification is the happy result of photosynthesis,” she says. “Plants suck carbon dioxide in through their leaves, convert it into energy to grow and exhale fresh oxygen as a by-product – nature’s purification system. Coincidently, the air sucked in contains toxins such as carbon monoxide, nitrous oxide and volatile organic compounds (VOCs).” 

Dyer continues: “While plants can therefore help to freshen the air in your home, it’s all about the numbers. Most plants suck in the bad and push out the good, each taking different VOCs out of the atmosphere. However, the air in our homes is constantly changing. Just when the plants get ahead, outside air rushes in through windows and doors, bringing with it pollution.

“With large amounts of ‘fresh’ air coming in, our plants are often outnumbered; they can’t filter the quantity of toxins quickly enough to have a meaningful impact on air quality. It’d take hundreds of plants in each room to really alter the air quality and even then, it’s minimal.” 

Indoor air quality might not be the first thing you think of when you wake up in the morning, but it’s definitely something that you should pay attention to.

“Air quality inside the home is a valid concern, especially considering that we often spend a significant amount of time indoors,” says Suzanne Wylie, GP and medical adviser for IQ Doctor. “Common indoor pollutants include dust, mould, pet dander and VOCs emitted from household products.”

Outdoor pollutants, like car fumes, can also enter the home through open doors and windows. However, keeping your home properly ventilated (eg allowing fresh air in from outside) is one way to stop indoor air pollution building up, so you don’t want to keep everything closed indefinitely.

Instead, it’s a good idea to take a few measures to keep your indoor air quality in check. Not doing so can lead to consequences down the line, Wylie adds: “Poor air quality can lead to various health issues, including respiratory problems, allergies, and even exacerbation of conditions like asthma. Long-term exposure to poor air can have more severe implications – including for your cardiovascular health.” 

If the quality of the air you breathe is important to you – especially in smaller, enclosed spaces – you shouldn’t rely on plants alone.

According to Wylie, there are plenty of easy ways to keep your indoor air quality in check. These include:

• Ensuring proper airflow by opening windows and using extractor fans in the kitchen
• Cleaning regularly to reduce dust build-up, especially with a vacuum cleaner
• Aiming for between 30-50% humidity to prevent mould growth (a dehumidifier can help with this)
• Using an air purifier with a HEPA filter
• Choosing low-VOC products such as furniture made from natural materials 

Images: Getty