Brain Health

Forgetfulness: What’s Normal, What’s Not

Originally published September 19, 2016

Last updated April 26, 2024

Reading Time: 3 minutes

How well do you remember what you did last week? Memory loss is not always a sign of aging. Learn about when you need to be concerned.

Misplace your car keys? Forget someone’s name? Lapses in memory happen to all of us, but there are times when we wonder whether these slips are normal.

Helena Chang Chui, MD, a neurologist at Keck Medicine of USC and chair and professor of neurology at the Keck School of Medicine of USC, is an internationally recognized Alzheimer’s disease expert, who helped us understand typical forgetfulness and when it may signal a more serious problem, such as dementia and, more specifically, Alzheimer’s disease.

According to Chui, growing older brings on changes throughout the body, including the brain. Mild forgetfulness is part of these changes. In contrast, “Alzheimer’s affects the memory areas of the brain,” explains Chui. “Not being able to learn new information or remember what just happened is an early symptom.”

However, unless the signs are dramatic and persistent, you shouldn’t worry about Alzheimer’s or other memory-loss diseases. Here are several ways to tell the difference between normal forgetfulness and something more serious.

What’s Normal

  • Absentmindedness. This usually occurs, when you aren’t paying close attention to the activity at hand.
  • Occasionally forgetting where you placed things.
  • Forgetting facts over time. Like computers, our brains need to purge old data to make room for new.
  • A “tip of the tongue” memory slip that you remember later.
  • Utilizing reminders to help you remember
  • Despite memory lapses, if your personality and mood remain the same, it’s a good indicator that it’s probably not something more serious.

Abnormal forgetting is more complex.

With dementia or Alzheimer’s disease, a patient’s memory fails but so do other abilities. The most obvious is a decline in self-care. Early signs of dementia are when memory loss affects work, hobbies and social activities.

“Over time, Alzheimer’s affects long-term memory, so the person keeps losing more and more of their old self,” Chui says. “The last to go are the youngest memories, usually from childhood.”

What’s Not Normal

  • Frequent pauses to retrieve words or memories
  • Forgetting recent events
  • When loved ones notice memory loss, before you do
  • Mood swings and personality changes also occur.
  • Difficulty performing simple, routine tasks, like paying bills and dressing
  • Getting lost in familiar places
  • Repeating the same conversation, over and over

At times, memory loss is related to lifestyle issues. You’ll know this is the cause, when you change your routine or consult a doctor, and your forgetfulness diminishes or goes away altogether.

Other Causes for Forgetfulness

  • Fatigue and lack of adequate sleep. Doctors know that rapid eye movement deep sleep plays a key role in memory.
  • Nutritional deficiencies. Vitamin B12, from foods like dairy products, fish and meat, is essential for normal nerve function.
  • High stress. If you have “too much on your plate,” you can become overwhelmed, which will make it difficult to remember all the tasks before you.
  • Depression
  • A medical issue. Silent strokes that go undetected can change brain function and deplete memory. Researchers have found that people with forgetfulness may be at a higher risk for stroke.
  • Medication. Some drugs list memory loss as a side effect. Metformin, a Type 2 diabetes drug, is linked to memory loss, as are some cholesterol drugs.

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Heidi Tyline King
Heidi Tyline King is a former magazine editor who has written for numerous national publications.