If you’re living with multiple sclerosis (MS), you’ve probably lost several minutes — if not hours — searching your house for misplaced items… only to find your keys or wallet somewhere random, like the kitchen pantry or medicine cabinet.

You’re not alone. Cog fog, or MS-related brain fog, affects many people living with MS. In fact, it’s estimated that more than half of people living with MS will develop cognitive issues like difficulty understanding conversations, thinking critically, or recalling memories.

MS-ers call this symptom “cog fog” — short for cognitive fog. It’s also referred to as brain fog, changes in cognition, or cognitive impairment.

Losing your train of thought mid-sentence, forgetting why you entered a room, or struggling to remember a friend’s name are all possibilities when cog fog strikes.

Krysia Hepatica, an entrepreneur with MS, describes how her brain works differently now. “The information is there. It just takes longer to access it,” she tells Healthline.

“For instance, if someone asks me a question about a particular detail from days or weeks before, I can’t always immediately pull it up. It slowly comes back, in chunks. It’s like sifting through an old-school card catalog instead of just Googling it. Analog vs. digital. Both work, one is just slower,” Hepatica explains.

Lucie Linder was diagnosed with relapsing-remitting MS in 2007 and says cog fog has been a significant issue for her, as well. “The sudden memory loss, disorientation, and mental sluggishness that can strike at any minute are not so fun.”

Linder describes times when she’s unable to focus or concentrate on a task because her brain feels like it’s slush in thick mud.

Fortunately, she’s found that cardio exercise helps her blast through that stuck feeling.

For the most part, cognitive changes will be mild to moderate, and won’t be so severe that you aren’t able to take care of yourself. But it can make what used to be simple tasks — like shopping for groceries — pretty darn frustrating.

MS is a disease of the central nervous system that affects the brain and spinal cord. It also causes areas of inflammation and lesions on the brain.

“As a result, [people with MS] can have cognitive issues that typically involve slowness of processing, trouble multi-tasking, and distractibility,” explains David Mattson, MD, a neurologist at Indiana University Health.

Some of the more common areas of life that are affected by cognitive changes include memory, attention and concentration, verbal fluency, and information processing.

Mattson points out that no one MS lesion causes this, but cog fog seems more associated with an increased overall number of MS lesions in the brain.

On top of that, fatigue is also prevalent in people with MS, which can cause forgetfulness, lack of interest, and little energy.

“Those who experience fatigue may find it more difficult to complete tasks later in the day, have a lower ability to withstand certain environments such as extreme heat, and struggle with sleep disorders or depression,” Mattson adds.

Olivia Djouadi, who has relapsing-remitting MS, says her cognitive problems seem to occur more with extreme fatigue, which can stop her in her tracks. And as an academic, she says the brain fog is awful.

“It means I get forgetful over simple details, yet can still remember complex items,” she explains. “It’s very frustrating because I know I knew the answer, but it won’t come to me,” she shares with Healthline.

The good news: There are immediate and long-term strategies for decreasing cog fog, or even just making it a bit more manageable.

Doctors and patients both feel frustration at the lack of treatment options available for the cognitive issues that accompany MS.

It’s critical for healthcare providers to offer support and validation to their patients with MS who are experiencing changes in their cognition, says Dr. Victoria Leavitt, clinical neuropsychologist at ColumbiaDoctors and assistant professor of neuropsychology, in neurology, at Columbia University Medical Center.

However, in the absence of treatments, Leavitt believes that lifestyle factors can make a difference. “Modifiable factors that are in our control can help change the way a person with MS lives to best protect their brain,” she tells Healthline.

Leavitt says the classic trio of modifiable lifestyle factors that may help with cognitive function include diet, exercise, and intellectual enrichment.


Changes to your diet — notably the addition of healthy fats — can help with cog fog.

Hepatica has found that eating healthy fats like avocado, coconut oil, and grass-fed butter help her cog fog.

Healthy fats, or foods rich in omega-3s, are known for their role in brain health.

In addition to avocados and coconut oil, include some of these to your diet:

  • seafood like salmon, mackerel,
    sardines, and cod
  • extra virgin olive oil
  • walnuts
  • chia seeds and flax seeds


Exercise has been studied for years as a way to help people with MS deal with the daily struggles of cog fog. In fact, a 2011 study found that physical activity was significantly correlated with cognitive speed in people with MS.

But it’s not just the favorable impact that exercise has on the brain that’s important. Engaging in physical activity is also good for the body and your mental health.

A 2013 study found that people with MS who participated in regular aerobic exercise experienced an increase in mood. When you feel good, you have a heightened ability to process information. Any type of exercise is beneficial, but researchers seem to look specifically at aerobic exercise and the role it plays in MS and cognitive function.

In addition, a 2016 study reported that people with MS who regularly exercised had a reduction in lesions in the brain, which shows just how powerful exercise can be.

Intellectual enrichment

Intellectual enrichment includes those things you do to keep your brain challenged.

Participating in daily activities such as word and number games, or thought-challenging exercises like crossword, Sudoku, and jigsaw puzzles, can help keep your brain fresh and engaged. Playing these or other board games with friends or family can also spark more benefits.

To get the biggest brain-boosting benefits, learn a new skill or language, or pick up a new hobby.

Short-term strategies

While implementing long-term solutions for cog fog is important, you’ll also likely benefit from some tips that’ll provide immediate relief.

Hepatica says some additional strategies that work for her when she’s experiencing cog fog are taking good notes, writing everything down on her calendar, and multi-tasking as little as possible. “It is preferable for me to start and finish tasks before moving on to start something new,” she says.

Mattson agrees with these strategies and says his patients do best when they make notes, avoid distractions, and do one thing at a time. He also recommends finding the time of day when you’re fresh and energetic and doing your more difficult tasks during that time.

In-the-moment strategies

  • Use an organization technique like lists or post-it notes.
  • Focus on doing one task at a time in a quiet, distraction-free space.
  • Use the time of day you have the most energy for the most difficult tasks.
  • Ask family and friends to speak more slowly to give you more time to process information.
  • Practice deep breathing to reduce the stress and frustration of brain fog.

Long-term game plan

  • Eat brain food packed with healthy fats or omega-3s like avocado, salmon, and walnuts.
  • Take a walk or indulge in another form of exercise you love regularly.
  • Learn something new to challenge your brain.

If you’re struggling with how to fit these strategies into your life, Leavitt says to talk with your doctor or medical team. They can help you come up with a plan to make these things work.

One tip she does like to stress is: Start small and set very realistic goals until you feel success. “You have to do things that you like for them to become a habit,” she says.

Leavitt is also looking into the role sleep, social networks, and connectedness with the community play in how people with MS deal with changes in cognition. She believes those factors along with aerobic exercise, diet, and intellectual enrichment are all excellent ways to protect against future decline.

“I see this as a really promising area for research,” she says. “Ultimately, we need to translate our evidence and our findings into treatments.”

While living with MS and dealing with cog fog can be a real challenge, Hepatica says she tries not to let it get her down. “I just accept that my brain works in a different way now and I’m thankful to have strategies that help,” she explains.

Sara Lindberg, BS, M.Ed, is a freelance health and fitness writer. She holds a bachelor’s in exercise science and a master’s degree in counseling. She’s spent her life educating people on the importance of health, wellness, mindset, and mental health. She specializes in the mind-body connection, with a focus on how our mental and emotional well-being impact our physical fitness and health.