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The Energy Reboot Blog

by Moira Newiss


Brain Fog: What Causes It & How To Clear It Quickly

This blog is for you if you have brain fog. It will help you understand some of the possible mechanisms that are going on in the body that cause the symptoms associated with brain fog. It will identify some of the triggers that can make it worse. And I will look at solutions, things you can do that will make a big difference to clearing your brain fog as quickly as possible.

There has been a global increase in the prevalence of fatigue and brain fog symptoms thought be as a result of problems with the interaction of the immune system and nervous system, partly due to Covid but the effect is also seen even among those never infected by the virus and thought to relate to other pandemic stressors. As you probably know we can’t really separate our body and mind just as we can’t separate one body system from another. There are likely multiple factors at play that have caused this increase in brain fog and as you will see there are multiple biological changes that interact to cause brain fog.

Brain Fog: What Causes It & How To Clear It Quickly

What Is Brain Fog?

Technically speaking brain fog in medical speak is a form of mild cognitive impairment. But please don’t panic at the thought of this, it does not mean you are getting dementia. People who have brain fog often describe it as feeling drugged, confused, forgetful, hazy, cloudy or having difficulty thinking, focusing, concentrating, remembering things and communicating. It is usually associated with a feeling of mental fatigue. The difficulty is that there is no test for it and no standard medical treatment. Often sufferers don’t get the answers they are looking for from their doctor.

Brain Fog

My Own Experience

I know how debilitating it can be because I have personally experienced severe brain fog when I ended up burnout with chronic fatigue. I felt like I had been drugged even though I wasn’t on any medications and certainly hadn’t been drinking. I felt a bit like the world was passing me by and I was struggling to be able to participate fully. I was worried about making mistakes at work and struggled to find the energy to hold simple conversations.

Medical Conditions

There are several medical conditions which brain fog is associated with including hypothyroid, long covid, burnout, chronic fatigue syndrome, POTs (post orthostatic tachycardia syndrome), celiac disease, fibromyalgia, mastocytosis, lupus, rheumatoid arthritis, SIBO (small intestinal bowel overgrowth), obesity, IBS (irritable bowel syndrome) autism spectrum disorders, MS (multiple sclerosis), mast cell disorder as well as early onset dementia.

Biological Process

There is research suggesting several mechanisms for why you might suffer from brain fog. The first is decreased cerebral blood flow which can be linked to blood pressure control which involves both the cardiovascular system and the nervous system. There are receptors in your blood vessels which are controlled by your nervous system and enable them to dilate (open) and constrict (close) to regulate your blood pressure.

What is brain fog?

If the blood flow in your brain is reduced then your brain cells will not be getting as much oxygen and nutrients delivered which they need to use to make energy. Just as in the rest of your body, your brain cells make energy in tiny little organelles called mitochondria using the oxygen and nutrients. If the mitochondria don’t get the right ingredients then they can’t make energy and you feel fatigued and your brain will struggle to function effectively.

Brain Fog - Poor Metabolism

Even if your blood flow is good some people struggle to get their nutrients into the cells to make energy in the first place. This can be due to something called insulin resistance when the glucose in your blood stream can’t be pulled into the cells. This is what happens when someone becomes diabetic and need more insulin provided to combat this resistance. Many people are insulin resistant and don’t know it, they are not diagnosed as a diabetic, but may struggle with brain fog and fatigue as you just can’t make energy.

Brain Fog - Neuroinflammation

Another reason for brain fog is neuroinflammation, inflammation of cells in your nervous system and brain. This can happen for a number of reasons including infections, trauma (accidents), mental stress as well as from environmental reasons like a poor diet and toxic chemical exposure. Inflammation can be linked with activation of the immune system, like during an infection. Mast cells are a type of white blood cells that can be activated and in turn release histamine which has an inflammatory effect. Plus histamine also plays a role as a neurotransmitter but too much of it can cause problems with cognition.

Brain Fog: What Causes It & How To Clear It Quickly

Blood pressure control is linked with the balance of electrolytes in our body. Electrolyte are salts like sodium, potassium, magnesium and chloride are involved in electrical impulse signalling (in our nervous system) as well as control of water retention and excretion and an imbalance in these salts can contribute to symptoms of fatigue, dizziness and brain fog.

Brain Fog: What Causes It & How To Clear It Quickly

There are also some specific nutrient deficiencies that are known to be linked to brain fog. With regards to energy metabolism and brain fog we know that B vitamins (B1, B2, B3, B5, B6, B8, B9 and B12), vitamin C, K iron, magnesium and zinc are all vitally important for good cognitive function. Anti-inflammatory nutrients such as Omega-3 and polyphenols (chemicals from colourful plant foods) are important too as well as avoiding inflammatory highly processed foods, refined carbohydrates and vegetable oils.

Brain Fog: What Causes It & How To Clear It Quickly

To function properly you brain (which is part of your nervous system) requires a number of amino acids found in protein foods. Amino acids such as tryptophan, tyrosine, histidine, and arginine are used by the brain to make various neurotransmitters and neuromodulators that are key for brain health. If you are lacking in some of the key amino acids in your diet and you are under high amounts of mental stress then your body may not be able to produce enough of these key brain chemicals.

Brain Fog: What Causes It & How To Clear It Quickly

There is now research showing that neuroinflammation may be linked to gut inflammation and an imbalance in our healthy and unhealthy bacteria in our gut. If we have too many unhelpful bacteria in our gut these can outcompete the good ones triggering our immune system to respond which in turn stimulates your immune system. This local inflammation in the gut can overtime lead to a condition known as ‘leaky gut’ or more formally intestinal permeability. When this happens molecules in the gut can leak through the lining and into the blood stream. These may be particles of undigested food or other toxins, they circulate and can pass into the brain and create brain inflammation.


Research shows that there are a number of triggers that can contribute to the onset of brain fog including a lack of sleep and sufficient quality sleep, poor nutrition, drugs/medication, prolonged standing and dehydration.


What can you do to shift your brain fog? The good news is that there are several things you can do. I am a big fan of synergistic effects which means layering up as many of these as you can to get the best effect, together they will have a greater impact on your brain health.

  1. If you are on medication, then tell your doctor about your brain fog and ask them to review your medication.

  2. Go to your kitchen cupboards and get rid of all the highly processed food that is hiding there. I mean biscuits, crisps, cakes, sweets. Give it away to a friend or a charity.

  3. Next time you go shopping swap your vegetable oil (sunflower, canola, rapeseed) for coconut oil, ghee, butter and olive oil.

  4. Add into your diet lots of colourful plant foods, focus on the ones that grow above ground so are lower in carbohydrates, like berries, tomatoes, carrots, peas, courgettes and peppers.

  5. Avoid tropical fruits that are high in sugars like bananas, mangos and pineapple.

  6. Load your shopping trolley with plenty of leafy greens like broccoli, kale, chard, cabbage, sprouts.

  7. Eat plenty of herbs and spices including turmeric.

  8. Make sure you are eating plenty of protein. Good sources include meat, fish, eggs and dairy along with vegetarian sources of legumes (beans and peas), lentils, tofu and xx. If you are vegetarian, you need to get several different types of protein sources in your diet and may need more as plant sources are less well absorbed by the body.

  9. Replace your carbohydrates. Swap your potatoes for cauliflower, your pasta for squash or courgette noodles, your sweet snacks for berries, chip for salad and cereal for yoghurt and flax seed.

  10. Eat plenty of food high in omega-3 fatty acids including oily fish like sardines, salmon, mackerel, anchovies and herring, nuts and seeds.

  11. Practice relaxation, give yourself permission and time to chill out and wind down from the day… try listening to music, reading, dancing, gardening, walking in nature, yoga, meditation or a relaxing bath.

  12. Avoid alcohol and drugs – give your brain the best chance!

  13. Get sufficient sleep, adults need around 8 – 9 hours of sleep for maximum health benefit.

  14. Fit some exercise into your daily routine. Brisk walking is the easiest to begin with but if you have chronic fatigue start with something more gentle like yoga.

  15. Make sure you get plenty of time outside getting sun exposure in the summer and take a vitamin D supplement over winter.

Many people may find it helpful to work with a nutritional therapist like myself to help identify the root cause of the brain fog in your case, to get help to rebalance the gut microbiome (gut bugs), balance blood sugar and reduce insulin resistance and consider the use of supplements that might be helpful such as resveratrol, curcumin, luteolin, mulberry extract, green tea, vitamins C & K and a multi-B vitamin complex.

Left unresolved brain fog can be life changing. I struggled to socialise and keep friendships going, to go to work and to work out how to organise simple daily tasks. Small simple changes in diet and lifestyle may have a quick and dramatic effect for many people but you may find you need to seek some expert advice to support you to make the right changes in the right order to find success.

If you are prepared to give this a go then your brain will thank you! You are helping it to make more energy by reducing inflammation and providing the right nutrients and conditions for it to thrive. As your body adapts its metabolism so will your brain and you will feel healthier and more energetic and your brain fog will clear!

Quick Start Keto Guide

To help you implement the best way of eating for brain energy download my Quick Start KETO guide which is packed full of tips and great recipes to get you started.

If you would like a copy of my Quick Start KETO Guide then you can download it by clicking here. It provides you will all the information you need to get started including 16 keto recipes, a meal planner and a condensed version of all the tips to get you into ketosis and avoid any problems.

If you would like to book a free call with me to see how I might be able to help you then please email me on

Disclaimer: Before changing your diet or lifestyle and taking any supplements always seek the advice of your doctor or another suitably qualified professional such as a nutritional therapist. The content of this blog is for informational purposes only and is not a substitute for professional medical advice. Always seek the advice of your doctor with regards to any questions you have about a medical condition.


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