16 Everyday Things That Are Making Us Dumber

Technology and modern society might be making us more efficient, but they sure aren't making us any smarter.

Put an end to these habits

Although the human brain has the power to adapt and change for the better, it’s also possible to damage your noggin. In fact, some of the things that hurt our brain, or make us less-bright, are everyday things like watching too much TV or having a glass of wine a little too often. Here’s what you should try to stop doing, or limit, for your bain.

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That late-night Netflix binge

We’re all chronically sleep deprived these days, and one of the first things to suffer when you lose zzz’s is your brain—and it doesn’t take much sleep loss to start impairing your mental abilities. “Study after study has shown that even an hour or two less sleep each night for just a few consecutive nights can have negative effects on the brain,” says Vernon Williams, MD, sports neurologist and director of the Center for Sports Neurology & Pain Medicine at Cedars-Sinai Kerlan-Jobe Institute. “From delayed reaction times that can put you in danger while driving to mental fatigue and depression, burning the midnight oil can have serious brain repercussions.” When looking to improve your sleep, make sure you avoid these sleep aids that are actually hurting your slumber.

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Your secret junk food stash

Candy, soda, fast food, and other modern inventions are one of the most common (albeit delicious) ways to drain your brain, Dr. Williams says. “One Australian study found that just five days of eating junk food could impair memory function, attention, speed, and mood,” he says. “The idea is that poor diet leads to inflammation in the brain, which can damage its structures.” (Instead, focus on the healthiest foods to eat in every decade of your life.)

young man working on the computer at home at night in the dark
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All that romantic mood lighting

Keeping the lights low may increase the feeling of ambiance (and make it harder to see the dirt on the floors!), but it won’t help your brain, according to a 2017 study in Hippocampus on rats. Researchers found that spending too much time in dimly lit rooms and offices may actually change the brain’s structure and hurt your ability to remember and learn, especially when it comes to spatial tasks.

Office worker writing notes in planner book
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Your multitasking lifestyle

Think that you’re an excellent multitasker and that doing several things at once makes you smarter? It’s likely having the exact opposite effect, says Joe Bates, MD, a psychiatrist and author of Making Your Brain Hum: 12 Weeks to a Smarter You. “Jumping from one thing to another without completing a task is training your brain to not focus on one thing, making you literally scatterbrained,” he says, adding that this leads to making bad decisions, feeling overwhelmed and frustrated, and forgetting important things. (Don’t miss these other 50 secrets your brain wishes you knew.)

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The constant notifications on your smartphone

Instead of using our phones as a handy tool we use to help us, many of us are letting technology control us, Dr. Bates says. The constant barrage of texts, emails, voicemails, games, and other alerts is a never-ending distraction, making it impossible to focus and think, he says. “This can turn into an actual addiction by programming the brain to want to keep checking your phone, as it gives you immediate gratification,” he explains. “Smartphones keep getting smarter and demanding our attention in even bigger ways, so for the sake of your brain health, you need to discipline yourself to engage thoughtfully and thoroughly and mindfully on projects throughout the day.”

Four hands with smart phones holding glasses with red wine, on wooden table background
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That glass (or three) of wine with dinner

Anyone who’s ever had a “deep” conversation with someone who’s had a few too many drinks knows how quickly booze can dumb you down. But did you know that overindulging in alcohol also has long-term harmful effects on your brain? “In addition to the possibility of impaired brain function as you age, drinking puts people at a higher risk for liver disease, strokes, depression, and many other diseases that also impair brain function,” says Mary Ellen Moore, DO, a family medicine physician with Advocate Christ Medical Center in Oak Lawn, Illinois. Put down that third glass and have one of these brain-boosting foods instead.

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Your 9 to 5… or 7 to 9

There is some truth to the old adage “work smarter, not harder.” When it comes to maximizing your mental abilities, working too much can have the opposite effect, making you a less creative and less accurate thinker, says Kate Martino, a physician’s assistant and weight-loss coach. Just like any other body part, your brain doesn’t do well with a lot of stress, and it needs to rest sometimes. “Stress can impact your memory, make you feel moody, make it hard to focus, and the longer you’re stressed out, the less brain clarity you’ll have,” Martino says.

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Your workspace at the local coffee shop

You may think that being able to work anytime anywhere is a major job perk, but setting up shop in a noisy environment, such as a coffee shop or airport terminal, could make it harder for you to work. Being surrounded by constant noise impairs the brain’s ability to learn new things and hurts your memory, according to a study published in Frontiers of Psychology. 

Airport Young female passenger on smart phone and laptop sitting in terminal hall while waiting for her flight
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Your fear of flying (or getting fired or being dumped or …)

A little angst keeps you alert and moving, but feeling a constant barrage of fear or worry can seriously impact your mental health and your ability to think clearly, says Farah Harris, a licensed clinical professional counselor. “When we are fearful, it is like our brain has been hijacked and we are unable to think rationally, see things clearly, be objective, and recall details,” she says. “By training your brain to try new things and face your fears, you can increase your alertness, improve memory, better manage stress, make better decisions, develop emotional intelligence, and increase your capacity and confidence.”

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Your deep dislike of fish

What you eat has a huge impact on how you think, starting with the types of fats you consume, says Rob Cole, licensed mental health counselor and registered dietitian, Clinical Director of Mental Health Services at Banyan Treatment Center. Eating foods high in trans fats, commonly found in processed snacks and fast food, hurts your brain health and has been linked in research to cognitive decline, he says. On the other hand, healthy fats, like those in wild salmon (and also nuts, chia seeds, and avocados), have been shown to protect brain cells and make your brain more efficient, he adds. Bonus: Healthy fats aren’t just good for your brain, they’re great for your whole body.

Cropped photo of attractive fitness woman sitting in gym and holding bottle of water.
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Your empty water bottle

Want to know the fastest way to drain your brain? Drain your body of water. Even mild dehydration can have profound effects on your mental capabilities, Cole says. “Drinking enough water is critical to ensure chemical balance in the brain,” he explains. Resist the temptation to substitute juice, soda, coffee, or other liquids, as the extra sugar can also impair your brain. Make sure you’re drinking plenty of pure, clean H2O on the regular.

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Your lack of vitamin D

Feeling confused, depressed, and indecisive? A walk in the fresh air and sunshine may be the best remedy. A 2014 study conducted by The American Academy of Neurology found that people with extremely low blood levels of vitamin D were more than twice as likely to develop Alzheimer’s disease or other types of dementia than those with normal levels, says Lauren Zimmerman Cook, CEO of AEC Living.

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Those pesticides you just sprayed on your grass

Call it a side effect of modern living, but we are surrounded by toxins in our air, in our water, and in our food. Unfortunately, these can take a toll on brain health, particularly as they accumulate over time, says psychotherapist Toni Coleman. Pollution can interfere with how your neurotransmitters function, both in your brain and in your gut’s microbiome, which regulate mood, thinking, memory, and cognition, she adds. You can’t avoid all environmental toxins (sadly), but you can start by eliminating these 11 household toxins making you sick.

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Your tendency to avoid reaching out

“Social isolation leads to loneliness, which can have a dramatic impact on your brain,” says Bryan Bruno, MD, depression specialist and medical director at Mid City TMS. “Without daily social engagement, the brain loses its ability to stay sharp and experiences a much higher chance of developing dementia. Those suffering from isolation show less neural activity in the brain’s ventral striatum, which is part of the brain’s reward center and plays an important role in learning.” Bottom line: Even if you’re an introvert, you still need other people.

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Your raging sweet tooth

Overdoing foods with added sugar, including “healthy” foods like juice and smoothies, can lead to poor cognitive function, says MaryAnhthu Do, MD, a neurologist with the Neurosciences Institute at Advocate Christ Medical Center in Oak Lawn, Illinois. It’s OK to have a treat sometimes, just make sure it’s a treat and not a staple, she says.

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The tablet propped up on your lap

Whether you’re constantly on your laptop, refuse to leave without your tablet, or are attached at the hip (literally) to your smartphone, all that tech is taking a toll on your brain, says Michelle Robin, DC, wellness practitioner and chiropractor. “Instead of having downtime and letting our minds wander, we reach for our phone as soon as we have to stand in line, when we do something as simple as walk down the hall, and while we are waiting for a meeting to start,” she says. Depending on devices to distract and entertain you keeps you from thinking deeply, being creative, working through problems, and connecting with the people around you, she adds. Next, check out the quirky habits of smart people.

Sources
  • Vernon Williams, MD, sports neurologist and director of the Center for Sports Neurology & Pain Medicine at Cedars-Sinai Kerlan-Jobe Institute
  • Hippocampus: "Light modulates hippocampal function and spatial learning in a diurnal rodent species: A study using male nile grass rat (Arvicanthis niloticus )"
  • Joe Bates, MD, a psychiatrist and author of Making Your Brain Hum: 12 Weeks to a Smarter You
  • Mary Ellen Moore, DO, a family medicine physician with Advocate Christ Medical Center in Oak Lawn, Illinois
  • Kate Martino, a physician's assistant and weight-loss coach
  • Frontiers of Psychology: "Does noise affect learning? A short review on noise effects on cognitive performance in children"
  • Farah Harris, a licensed clinical professional counselor
  • Rob Cole, licensed mental health counselor and registered dietitian, Clinical Director of Mental Health Services at Banyan Treatment Center
  • Neurology: "Vitamin D and the risk of dementia and Alzheimer disease"
  • Lauren Zimmerman Cook, CEO of AEC Living
  • Toni Coleman, a psychotherapist
  • Bryan Bruno, MD, depression specialist and medical director at Mid City TMS
  • MaryAnhthu Do, MD, a neurologist with the Neurosciences Institute at Advocate Christ Medical Center in Oak Lawn, Illinois
  • Michelle Robin, DC, wellness practitioner and chiropractor
Medically reviewed by Renata Chalfin, MD, on March 30, 2021

Charlotte Hilton Andersen
Charlotte Hilton Andersen, MS, is an award-winning journalist, author, and ghostwriter who for nearly two decades has covered health, fitness, parenting, relationships, and other wellness and lifestyle topics for major outlets, including Reader’s Digest, O, The Oprah Magazine, Women’s Health, and many more. Charlotte has made appearances with television news outlets such as CBS, NBC, and FOX. She is a certified group fitness instructor in Denver, where she lives with her husband and their five children.