Forgetting Things Lately? 6 Things That Could Be Causing Those Memory Slips

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Keep forgetting things? Can’t seem to remember where you left the car keys and struggle to remember what you needed at the grocery store? Can’t remember your name? Now that one’s a little more serious. 🙂


If things are slipping your mind more often, you may wonder whether you’re simply forgetful or in the first stages of Alzheimer’s disease. I think that goes through most people’s minds occasionally unless you’re under the age of 30! 


The reality is there is some slow-down in brain function with age but being forgetful doesn’t necessarily mean you’re destined to develop Alzheimer’s disease.


It’s not uncommon with age to have problems remembering a person’s name that you don’t see very often or forget where you put something, although some of these instances are more concerning than others.


It’s perfectly normal to forget where you left your car keys. However, putting your car keys in an inappropriate place, like the refrigerator, is a red flag that more serious changes in brain function may be happening. 


But, if you’re just a bit more forgetful lately, there’s a good chance that nothing sinister is going on. In fact, there are other common causes of “memory slips” you should be aware of.


Here are five of the most common reasons you could be more forgetful lately:

Lack of Quality Sleep


Ever notice when you don’t reboot your computer for a while everything slows down? The same happens to your brain. Sleep is the time your brain “reboots,” releasing information in short-term memory to long-term memory so you can remember it later.


Your brain needs this downtime. Just as you, on occasion, need to reboot your computer to get it to speed up, you need to give your brain a fresh start as well.  


Research shows most memory processing occurs during deep or slow-wave sleep. People experience less slow-wave sleep as they age. That may partially explain why memory problems become more common with age. We don’t spend the same amount of time in deep sleep. 


Sleep is vital for healthy brain function. 


Does this apply to you? If you’re “burning the midnight oil” and not getting a good night’s sleep, those annoying memory slips may become more frequent. Where did I park that car again? This is especially true as you age.


Research has correlated a reduction in deep sleep with memory impairment the following day. A number of studies show sleep improves memory in people of all ages.


It can even help you when you study for a test. Want to remember a list of words? Memorize them before taking a nap. Studies show you’ll remember more words than if you didn’t take a nap. Sleep, even a short nap, can enhance your memory.




Are you a multi-tasker? Multi-tasking can make you more forgetful and less productive. Studies show our brains don’t respond well to switching from task to task. Overloading your brain with too much information, particularly asking it to perform too many complex tasks at once, can cause forgetfulness because you’re asking your brain to process too many pieces of information at once. 


Needless to say, we’re more distracted than ever by technology, so it’s not surprising that we’re more forgetful. Multi-tasking becomes is even more problematic in older people who can’t switch back and forth between tasks as efficiently. If you’re forgetting things lately, make sure you’re not trying to tackle too much at one time.



Sleep is important, but watch out what you take to help you sleep. If you can’t sleep and try to change that by taking a sleeping pill, you may be forgetful and a little “loopy” the next day. But sleeping pills aren’t the only medications that can leave you struggling to remember things.


Medications used to treat pain, drugs used to treat anxiety or depression, muscle relaxants, antihistamines and even some blood pressure medications can cause “brain fog” and problems remembering.


Don’t forget about the other “drug” that causes memory problems – alcohol. If you’re having more memory slips, ask your doctor if one of your medications could be a factor.




Stress can make you forgetful too. When you’re under stress, your body releases stress hormones like cortisol into your bloodstream. These hormones make it harder to recall information.


Have you ever noticed when you’re under stress it’s hard to think? That’s due to the action of stress hormones on your brain. Both acute and chronic stress can make you forget things.


It’s okay to forget sometimes – but don’t forget your purpose!




Depression can cause forgetfulness and mild memory disturbances too. How so? When you’re depressed just like when you’re stressed, you have higher levels of stress hormones like cortisol that impact a portion of your brain called the hippocampus.


The hippocampus is important for memory recall. When you’re trying to recall something, your hippocampus fires. The hippocampus also plays a role in forming long-term memories.


Medications used to treat depression can also cause memory problems and forgetfulness too.


Vitamin Deficiencies


Two vitamin deficiencies commonly cause memory problems – deficiency of vitamin B1, also known as thiamine, and vitamin B12. Thiamine deficiency is most common in alcoholics.


Vitamin B12 deficiency can occur at any age but is most frequent in people over the age of 55. You can eat a healthy diet and be low in vitamin B12 due to difficulty absorbing it from your intestinal tract. This can occur for a variety of reasons.


People who eat a vegetarian or vegan diet for many years are at higher risk since vitamin B12 is found naturally only in meat and dairy, although some foods are fortified with it.


Fact: We’re more likely to remember things associated with strong emotions. 


Vitamin B12 deficiency is a very serious and not uncommon health problem that can permanently damage your nervous system.


If you’re experiencing recent memory problems, have your doctor check a vitamin B12 level. If you have difficulty absorbing vitamin B12, sublingual vitamin B12 that you place under your tongue is one way to get your B12.


Dr. A and I have both seen patients with low vitamin B12 that were having memory issues. In fact, there are cases of older people diagnosed with Alzheimer’s disease who were actually experiencing severe vitamin B12 deficiency.


You must catch the symptoms early as vitamin B12 deficiency can cause permanent nerve and brain damage if you don’t correct it. 


Medical Problems


If you’re forgetting things lately, it could be due to an undiagnosed medical problem. Two conditions that commonly cause memory problems are sleep apnea and an underactive thyroid.


Thyroid gland problems commonly cause forgetfulness.An underactive thyroid can also cause other symptoms like fatigue, weight gain, problems concentrating, dry skin or constipation.


What’s less well appreciated is sleep apnea can cause problems with memory too. It damages parts of the brain called mammillary bodies that store memories. Sleep apnea is where you stop breathing for periods of time throughout the night. Reduction in oxygen flow to the brain when you stop breathing seems to cause the damage.


If you’re obese, have a headache or dry mouth when you wake up or snore frequently at night, talk to your doctor. Sleep apnea is a serious condition that needs treatment.


One study showed memory changes may signal an increased risk for stroke. If you’re concerned about your memory, see your doctor. Your doctor can do a series of verbal tests to make sure your memory changes aren’t serious.



Keep Forgetting Things: When You Should Be Concerned


If memory problems are new to you or they’re getting worse, it’s a sign you need to see your doctor. If the problem isn’t getting worse, make sure it’s not your medications. Then focus on getting seven to eight hours of uninterrupted sleep.


Watch your diet too if you’re forgetting things lately. Foods that are good for your brain include walnuts, pistachios, and blueberries.


Lastly, don’t underestimate the power of exercise. Research shows aerobic exercise helps your brain forge new connections and even make new nerve cells. Make sure you’re getting at least 30 minutes of aerobic exercise three or four days a week.


Here’s a link to a brief quiz to test your memory:


Memory Test


Brain Healthy Habits:


  • Exercise (especially aerobic exercise)
  • Mediterranean diet (lots of plants)
  • 7+ hours of sleep nightly
  • Learn a second language or a new skill
  • Limit alcohol 
  • Don’t smoke
  • Reduce the amount of sugar in your diet
  • Protect your head from injury
  • Check your hearing. Hearing loss can worsen brain function
  • Get outside in nature more. Give your brain a rest. 





Harvard Business Review. “The Simplest Way to Reboot Your Brain”
National Science Foundation. “The Connection Between Memory and Sleep”
Medical News Today. “Poor Sleep Causes Memory Loss And Forgetfulness”
Journal of Neuroscience, 25(11), 2977-2982. (2005) “Cognitive Problems May Signal Increased Stroke Risk”
The New York Times. “Common Sleep Problem Linked With Memory Loss”
The DANA Foundation. “Move Your Feet, Grow New Neurons?”
Psychology Today. “The Myth of Multi-Tasking”

Kristie Leong M.D.

Dr. Kristie Leong and Dr. Apollo Leong are physicians helping you to lead a healthy lifestyle by sharing nutrition and fitness tips and keeping you abreast of the latest health news.