What Causes Brain Fog? Here Are 3 Simple Tricks to Clear It, By an RD

Have you experienced difficulty concentrating, not feeling as ‘sharp’, along with low energy and mental fatigue? Perhaps you have also been told by a medical professional that you have nothing wrong with you? Well, if you answered 'yes,' it sounds like you could be experiencing brain fog.

Let’s discuss what exactly brain fog is, the causes, and how we can change our diet to beat brain fog.

Brain fog, otherwise known as functional cognitive disorder (FCD), can be described as cognitive dysfunction in the absence of underlying brain pathology.  In other words, it’s characterized by a subjective set of symptoms that can’t be diagnosed through conventional medical tests. You know it when you have it. Symptoms can range from any of the following:

The symptoms of brain fog can overlap with many medical conditions such as Multiple Sclerosis (MS) or Obstructive Sleep Apnea or can be a side effect of some medications. Your medical practitioner would need to address and rule out these factors.

Brain fog does rarely occur as a stand-alone symptom and there is often an underlying cause.

In addition to digestive problems after eating a certain type of food, fatigue, headaches, and brain fog can also emerge as symptoms of food sensitivities or food allergies.

Documented foods that folks have developed sensitivities or allergies to, resulting in symptoms such as brain fog include wheat, histamines, FODMAPS, alcohol, dairy, and artificial sweeteners.

We knew this one was coming! Poor sleep quality can interfere with brain processing. When your brain is exhausted, it becomes harder to think and focus.

About ¾ of your brain is composed of water and when dehydrated, your brain actually shrinks in volume. Even milk or temporary dehydration can alter your brain function. Studies have shown that even a drop of 2% in body water can impact your short-term memory and experience problems with focusing.

If our blood sugar is often too high or too low, brain fog can be a symptom.
High blood sugar can damage blood vessels, resulting in poor blood circulation and when there’s insufficient blood circulation in the brain, you may not think as clearly.

Additionally, low blood sugar or hypoglycemia can have a similar effect, resulting in brain fog. When the body doesn’t receive enough glucose for energy, brain cells can’t function properly.

Again, I want to emphasize that it is important to speak to your family physician, to rule out underlying medical concerns that could be contributing to brain fog. Other lifestyle modifications can include:

Take extra care to make sure that your diet is full of complex, high-fiber carbohydrates (for blood sugar balance) and is rich in B vitamins and iron. Foods that are rich in B vitamins include peanuts, oats, soybeans, wheat germ, bananas, broccoli, brussels sprouts, leafy greens, chickpeas, and nutritional yeast. Iron-rich foods that you can incorporate into your diet every day include white beans, lentils, dried fruit, cooked spinach, and pumpkin seeds. To make the iron from these sources absorb better, pair them with a vitamin C source (such as red pepper or citrus fruit) and avoid drinking coffee/tea at meals that contain them. Coffee and tea contain compounds that can inhibit iron absorption!

If you suspect a food sensitivity, please speak to a medical professional, such as a Registered Dietitian about this. An elimination diet can be very helpful to rule out potential sensitivities – I’ve seen success with my clients around this! A caution about food sensitivity tests – they aren’t always accurate and could lead you to an unnecessarily restricted diet. Work one-on-one with a Registered Dietitian and discuss if an elimination diet is right for you.

Moving more can assist with better sleep, along with boosting blood flow to the brain. Many studies have shown that aerobic exercise in particular improves thinking skills. As well, there is no better time than now to develop a nighttime routine and put down that blue light so your brain can get some well-deserved rest. Also, that nightcap before bet is probably not helping you any, as that can perpetuate brain fog.