Ever feel like your mind is working in slow motion? Whether it’s forgetting where you left your keys or being off your game at work, brain fog can show up in just about every aspect of your life.

Common signs of brain fog include everything from poor memory and cognitive function, to difficulty focusing and feeling ‘spaced out’, to decreased productivity and inability to deal with life’s stressors, as well as lack of energy, creativity, and motivation, explains doctor of natural and integrative medicine Rachel Eva Dew, D.N.M., D.I.M., Ph.D., co-founder and CEO of ModiHealth. Thankfully, for most people, brain fog and mental fatigue are usually temporary. In fact, in many cases, the haze is caused (or exacerbated) by lifestyle factors—which means that, with a little effort, you can get back to full-steam-ahead status instead of feeling like you’re running on fumes.

Here, experts break down six of the most common culprits behind brain fog, plus how to start clearing up that cloudy thinking.

1. The Obvious: You Don’t Sleep Well

Unsurprisingly, lack of quality sleep is one of the main culprits behind brain fog, states the Sleep Foundation. And according to the latest statistics from the American Sleep Association (ASA), between 50 and 70 million Americans have some type of sleep disorder, with insomnia making the top of the list (30 percent reported short-term issues while 10 percent deal with chronic insomnia). 

“It’s simple: Your brain needs to rest, reset, and reboot,” says Dew, adding that all sorts of hormone-managing processes occur during sleep.

How To Lift The Fog: The Centers for Disease Control and Prevention (CDC) recommends that adults should clock in at least seven hours of sleep each night, but Dew says that improving sleep hygiene is key. The ASA offers a number of strategies for creating healthier sleep habits and boosting sleep quality, such as nixing afternoon naps and caffeine consumption, establishing a relaxing nightly bedtime ritual (like a warm bath and/or meditation), keeping screens (yes, all of them) out of the bedroom, and going to sleep and waking up at the same time each day (even on the weekends). 

2. You Don’t Eat Enough Healthy Fats

A lack of balanced nutrition can leave you feeling out of focus for a number of reasons—and falling short on healthy fats is a big one, says Dew. You see, two studies published together in Nutritional Neuroscience found that polyunsaturated fats (omega-3s and omega-6s) in the blood could have a positive effect on brain structures associated with memory and “fluid intelligence,” or the ability to solve new problems.

How To Lift The Fog: For starters, the U.S. National Library of Medicine recommends reducing your intake of fried foods. Then, add more “good fats” (monounsaturated and polyunsaturated fats) to your day by either grilling fatty fish (salmon, tuna, or mackerel), sprinkling seeds (sunflower, pumpkin, or flax) and nuts (almonds, peanuts, cashews) in smoothies, salads, or yogurt, or sauteeing vegetables in extra-virgin olive oil, suggests Ward.

3. You Follow A Low-Carb Diet  

If you’ve been forcing yourself to stay on the low-carb train despite not feeling so hot, know this: “A low-carbohydrate eating plan can leave you fuzzy, less energetic, and struggling to retrieve details,” says dietitian Elizabeth Ward, R.D.N., co-author of The Menopause Diet Plan: A Natural Guide to Hormones, Health, and Happiness.

For many people, the low-carb trend is one of the sneakier culprits behind brain fog these days, since your body, including your brain, uses carbs for energy. In fact, one small study published in Appetite reported that women who followed a low-carb diet scored worse on memory tests than those who ate a balanced, lower-calorie diet. 

How To Lift The Fog: “Approximately 40 percent of your calories should come from foods that are rich in ‘good’ [or ‘complex’] carbohydrates and other nutrients (like fiber),” suggests Ward. These include starchy veggies, such as peas, corn, and yams, as well as whole-grain bread, cereal, and pasta.

Read More: Keep Your Brain Sharp As You Age With These 6 Simple Tactics 

The National Institutes of Health (NIH) also recommends eating cooked beans, peas, and lentils, opting for whole fruit over juice, and eating fruits and vegetables with the skins on. 

4. You’re Low On B12

Take note, vegans and vegetarians. “People who don’t eat animal foods (or who skimp on them) may not get enough vitamin B12, which is important to the nervous system and can lead to lethargy,” explains Ward. One long-term impact? A review published in the journal Nutrients that reported on four studies found a link between low vitamin B levels and an elevated risk of cognitive decline.  

How To Lift The Fog: If you’re concerned you don’t get ample B12 through your diet, “take a vitamin B12 supplement that contains 100 percent of the Daily Value,” says Ward. (According to the NIH, that’s 2.4 micrograms for adults.) Eating fortified foods, such as breakfast cereal, daily can also help—but may not offer enough to replace a supplement.

5. Your Hormones Are Shifting

Sad but true: Changing hormone levels that come with aging can also result in cloudy thought patterns.

For women in their 40s and 50s, increased brain fog may be the result of declining estrogen levels. “Some women may not even realize they are feeling less mentally sharp because of perimenopause and menopause,” Ward explains. While research on cognitive decline and menopause transition is minimal, researchers from Baylor University and University of Bologna, Italy have reported that brain fog continues to be a top complaint among peri- and post-menopausal women. 

Read More: What Are Nootropics and How Do They ‘Boost’ Your Brain Power?

As men age, meanwhile, they gradually lose testosterone, which is associated with impaired memory and recall, Ward continues. 

Age aside, though, changes in the hormones insulin (which regulates blood sugar) and cortisol (a.k.a. the stress hormone) can result in foggy thinking in both women and men if diet and stress are out of whack.

How To Lift The Fog: Some good news for middle-aged women: “The brain is resilient and adapts to these changes, which generally ease once menopause has occurred,” says Ward. Whether you’re a woman in menopause, a man experiencing declining T, or suspect other hormones are impacting your noggin, Ward recommends eating fatty fish twice a week, consuming plenty of plant-based foods, limiting alcohol, and exercising multiple times a week to support it.

6. You’re Dehydrated

Skimping on H2O impacts your health in a lot of ways—and it just so happens to be one of the biggest culprits behind brain fog, too. In fact, a study conducted by professors at Georgia Institute of Technology discovered that athletes who lost fluids that equaled two percent of their body weight (which is defined as mild to moderate dehydration) showed signs of brain fog, specifically a lack of attention and impaired decision-making skills.

And, according to Dew, low-level dehydration is a common issue many people face. In fact, the latest statistics from the CDC suggest that Americans consume an average of 39 ounces of water each day—much less than the standard recommendations.

How To Lift The Fog: To ensure you’re providing your body with enough fluids, “be sure to drink enough clean filtered water, which is typically a minimum of half your body weight in ounces of water each day,” says Dew. “For example, if you weigh 200 pounds, a minimum of 100 ounces of water a day is recommended.”