That annoying feeling of being unable to concentrate, a word on the tip of your tongue you just can’t seem to remember, inability to multitask, or just feeling spacey…
We’ve all experienced it, whether it be with a common cold, after a poor night’s sleep, or the morning after a really great party. Regardless of when or how we got it, it’s unpleasant, and leaves us feeling less than our best.
So exactly what is brain fog and how can we treat it and prevent it?
What is brain fog?
Here’s what the Mirriam-Webster dictionary has to say about “brain fog”: N. a usually temporary state of diminished mental capacity marked by inability to concentrate or to think or reason clearly.
Fortunately, most brain fog is temporary, as the above definition suggests. Brain fog that persists is a bit more concerning, and is characterized as a symptom of CFS, Chronic Fatigue Syndrome2. In 1994, the Centers for Disease Control (CDC) actually defined CFS as a set of known symptoms that last for six months or longer, including an inability to concentrate and feeling of “being stuck in a fog”.
Just to be clear, Chronic Fatigue Syndrome has other physiological symptoms like muscle aches that are not a part of what we’re addressing here as brain fog. We’re talking about the temporary condition of inability to focus and feeling of just not being sharp.
Either way, if you have brain fog, you want it gone, and if possible, you’d like to avoid it altogether. Let’s start with how one gets brain fog in the first place. For the purposes of this article, we’re limiting our discussion to brain fog that comes and goes, and not cognitive decline, dementia, or Alzheimer’s. That’s a much bigger discussion.
So, here goes.
What causes brain fog?
Lack of sleep
The human brain needs a lot of energy. Pound-for-pound, the brain (3 lbs./1.33 kg) needs more energy than any other organ, including the muscles (Wang, et al). When less energy is available to it, there are consequences, and dim-wittedness is one of them. Here’s an excerpt from the study, as published in the American Journal of Clinical Nutrition (text bolding added):
Mental and physical fatigue are experienced when these do not meet ongoing demands of the brain and muscles respectively. Under resting conditions, the fractional daily energy expenditure is the highest for heart and kidney (each approximately 440 kcal/kg), then for the brain (approximately 240 kcal/kg), then the liver (200 kcal/kg), while the resting skeletal muscle would need only approximately 13 kcal/kg. However, after considering the average adult weight of these organs, brain (1.33 kg) and muscle (26.3 kg) emerge as the most metabolically active structures, even at rest.1
As far as preferred fuels go, the brain likes glucose, and glucose means carbs. Consequently, low-carb diets like keto–with its notorious “keto flu”–are going to put a strain on your brain. Interestingly though, moderate calorie restriction (not to be confused with nutrient restriction) has been shown to improve thinking (aka “cognitive function”).
Now, the body is pretty clever and can manufacture other fuels for the brain, but glucose is your noodle’s go-to energy source. But if you choose a carb-restricted diet over portion control or other more-balanced diet program to lose those extra pounds, expect some brain fog, at least temporarily. The same would hold true for any extreme calorie-restricted diet that borders on malnutrition.
The brain also depends on certain micronutrients for proper function. Simply managing macros–carbs, fats, and protein–isn’t’ enough. Vitamins B1 (Thiamine), B2 (Riboflavin), B3 (Niacin), B9 (Folic Acid), B12, and Vitamin C are standout micronutrients essential for optimum brain development and function. The B vitamins in particular support metabolic processes that in turn provide other key nutrients to the brain.
Stress can make you stupid. OK, that’s overstating things a bit. However, clinical research has shown that anxiety and its related hormone, cortisol3, can negatively impact a person’s ability to remember things. It gets more complex than that, but in general, we think better when relaxed and stressed out.
At Cambridge, in 2016, Cheke, Simons, and Clayton NS published a paper that linked Higher Body Mass Index (obesity) to memory impairment, emphasizing the importance of good nutrition (and exercise) to overall health.
How to treat brain fog
We’ve discussed now what brain fog is, and what brings it on. What about fixing it? Prevention, diet, and supplements can help.
Because it’s preventative for brain fog, sleep is a good place to start. Good sleep begins with good sleep hygiene.
Here are a few tips that most authorities on sleep agree upon:
- Establish a sleep routine. Have regular bed and wake times and a bedtime routine, absent of blue-light devices like cell phones or tablet computers.
- Optimize your sleep environment. A cool, dark room, along with a comfortable mattress and pillow, with soothing aromas like lavender, are known to help people sleep better. White noise devices or audio loops with relaxing sounds of nature or music can also be helpful.
- No electronics a couple hours before bed, and if you wake, don’t pick up the phone, tablet, or laptop. These devices produce unnatural light and stimulate your waking mechanisms triggered by melatonin.
- Avoid caffeine and be careful with daytime naps. It’s best to head to bed tired, not wired.
- Take it easy on the alcohol. It may seem counterintuitive, but that drink that gets you drowsy can wake you up in the middle of the night as your body starts metabolizing the alcohol, turning it to sugar.
What are the best supplements for brain fog?
A diet rich in all the necessary brain-friendly nutrients can prevent brain fog. Sometimes, balanced eating isn’t in the picture. So we turn to supplements. There are a number of supplements marketed for better brain function.
We did a little research into the best supplements to combat brain fog. This list is by no means exhaustive. Here we share three that kept coming up and appeared to have the most clinical evidence supporting them.
B5 (Pantothenic acid)
All the B vitamins work with the body to convert carbs to energy, and because the brain needs both, B vitamins are helpful brain food and can fight brain fog. The standouts are B1, B6, B9 and B12.
B vitamins are found together in lots of foods people enjoy. Diets that restrict certain foods can deprive you of this crucial vitamin complex. Because many of the sources for B vitamins come from fish and animal sources, people on vegan diets have fewer natural sources.
Footnote: It’s ironic that several foods commonly encouraged in the low-to-no-carb diets are loaded with B vitamins, but those same diets restrict the carbs that B vitamins help metabolize, which in turn leads to brain fog.
Luteolin6 is a flavonoid, a family of chemicals found in plants and known for their antioxidative properties. They’ve been used for centuries in Chinese herbal medicine for treatment of various diseases such as high blood pressure, cancer, and inflammatory problems (Lin et al).
Luteolin supplements are available over-the-counter and are marketed for improvement of memory.
Omega 3 (𝛀-3) Fatty Acids
The Omega fatty acids7 are unsaturated fats that must be consumed either in the diet or in supplements. The body does not produce these. Omega 3 in particular has been associated with brain health and so makes a good choice when combating brain fog.
Foods rich in Omega 3 are:
- Oily fish, like salmon and mackerel
- Chia seeds
- Flax seeds
Because the omegas are so strongly associated with brain–and heart–health, and because the body depends on external sources for these, it’s never a bad idea to have them handy in supplement form.
Here’s a list of a few other supplements worth a try7 if you’re experiencing brain fog:
- Vitamin D
- Vitamin E
Brain fog can be expected as an occasional side effect of a fast-paced life and dietary constraints, whether intentional or not. Knowing what causes it, how to prevent it, and a few supplements to keep handy can make brain fog episodes infrequent and short-lived.
- Wang Z, et al. “Specific metabolic rates of major organs and tissues across adulthood: Evaluation by mechanistic model of resting energy expenditure”. American Journal of Clinical Nutrition. 2010; 92:1369–1377.
- Ocon AJ. “Caught in the thickness of brain fog: exploring the cognitive symptoms of Chronic Fatigue Syndrome”. Frontiers in Physiology. 2013; 4: 63.
- Robinson OJ, et al. “The impact of anxiety upon cognition: perspectives from human threat of shock studies”. Frontiers in Human Neuroscience. 2013; 7: 203.
- Gestuvo MK, Hung WW. “Common dietary supplements for cognitive health”. Aging Health. 2012; Feb; 8(1): 89-97.
- Tardy A-L, et al. “Vitamins and Minerals for Energy, Fatigue and Cognition: A Narrative Review of the Biochemical and Clinical Evidence”. Nutrients. 2020; Jan; 12(1): 228.
- Theoharides TC, et al. “Brain “fog,” inflammation and obesity: key aspects of neuropsychiatric disorders improved by luteolin”. Frontiers in Neuroscience. 2015: 9: 225.
- Gomez-Pinilla F. “Brain foods: the effects of nutrients on brain function”. National Review of Neuroscience. 2008 Jul; 9(7): 568–578.