First came Marie Kondo’s internationally best-selling book, The Life-Changing Magic of Tidying Up, then the backlash, and then Netflix’s hit show, Tidying Up with Marie Kondo. Watching real people’s lives transform over weeks as they clear out physical and emotional baggage makes this message even more powerful. Her book remains one of the most insightful I’ve read about how the state of our surroundings directly impacts our lives.

According to Kondo, who was once a Shinto shrine maiden and had been tidying up since kindergarten, a dramatic home reorganization can create dramatic changes in lifestyle and perspective. Recent research on the effects of clutter–both on our brains and the environment–appears to back her claims.

In essence, Kondo believes you should surround yourself only with the things you love. Her method does not rely on buying elaborate storage systems (she calls storage experts “hoarders”) but instead requires discarding unnecessary belongings. She takes each item in hand and asks: “Does this spark joy?” If it does, it stays. If it doesn’t, it goes. “The question of what you want to own is the question of how you want to live your life,” says Kondo.

According to the Princeton University Neuroscience Institute, Kondo’s theory has scientific support, as recently reported in The Washington Post. The institute’s study, “Interactions of Top-Down and Bottom-Up Mechanisms in Human Visual Cortex,” shows the negative impact of visual stimulation (a bottom-up mechanism) on focus (top-down) attention. The findings show that due to how our brains process visual information, it takes more energy to focus attention in an environment in disarray than in an orderly one. All that extra “stuff” subconsciously competes for your attention, adding unneeded stress and tension to your life.

Our excess belongings can also be a drain on the environment. According to a recent article by Lloyd Alter in Mother Nature Network, “Even as our houses get more [energy] efficient, they get bigger, and we fill them with more stuff, pretty much negating the efficiency gains.” With their increased square footage, new homes have more computers, TVs, cable boxes, and video game systems and consume about 18% more energy on average than older, smaller homes.

As an architect, clients often request more storage when building a new home or remodeling. In some cases, there is a clear need for space for sports equipment for active families or a new kitchen that is better organized (but not necessarily bigger). I also see many things that are not bringing joy to anyone’s life—no one needs that much Tupperware—and could go to Goodwill without being missed. Construction costs are climbing, and that extra 8-foot-by-2-foot closet to hold clothes you haven’t worn in ten years (Hey, they’ll fit again someday!) could cost you $5,000.

Sometimes, there is a need for creative storage that doesn’t exist in many homes, what I call the drop zone, for efficient organizing of the items that come into a house daily. Storage space that is the end-of-the-line for items that aren’t used daily—or ever–is a drain on the home, especially when that square footage could be a reading nook, room for a freestanding soaking tub in the primary bathroom, or a sauna. Instead of building more storage, allow more open floor space for kids to play or make room for your creative activity—painting, printmaking, practicing music.

An uncluttered home also allows one to sit quietly and watch the light change in a visually quiet space. We all seek that serenity and inspiration, which is why Kondo’s book has sold over 11 million copies worldwide. Now that I’ve finished it, she would ask me to thank it and discard it, but it brings me joy, so it’s staying.