We all know what it’s like to feel as if we’re walking around in a complete daze. Going through the motions of daily life, our bodies might feel somewhat energized, but our brains just can’t seem to keep up—almost as if we’re processing thoughts and information in slow motion and can’t concentrate on anything for more than a couple of minutes.

A lot of us will go through periods like this depending on the stage of life we’re in, especially if things are more stressful than usual. But some of us struggle with brain fog consistently for months or even years, with no idea why. The truth is—if we don’t know the cause, we can’t fix it. And it’s safe to say no pill is going to make it magically go away. That means we need to be our own little detectives and find out what’s going on.

Most of us are now very well aware that the gut and brain are connected because it’s been nonstop talked about for years. Yes, it’s true that a lot of the time brain fog results from what you’re putting in your mouth; however, there are a few other contributing factors we need to keep in mind.

Below, I’ve listed the top 8 root causes of brain fog to give you the knowledge to make informed decisions on how to tackle it.

1. Nutrient Deficiencies

This is arguably the most common cause of brain fog! Some key nutrients to look at would be:

  • Vitamin B12 – Essential for brain and nerve function. Low levels can cause memory issues, fatigue, and mental confusion.
  • Iron – Needed to deliver oxygen to the brain. Deficiency can lead to poor concentration and fatigue.
  • Vitamin D – Supports mood and brain health. Low levels are linked to depression and cognitive issues.
  • Omega-3s (EPA/DHA) – Crucial for brain structure and signaling. Deficiency may cause memory problems and low mood.
  • Magnesium – Helps with stress response, sleep, and brain function. Deficiency often leads to anxiety and mental fatigue.
  • Zinc – Important for mental clarity and neurotransmitter balance. Low zinc may cause foggy thinking.
  • Choline – Supports memory and learning. Deficiency can slow mental processing.

2. Blood sugar imbalances

Brain fog is often linked to blood sugar imbalances. When you eat high-sugar or refined carbs, your blood sugar spikes, then crashes—leaving your brain without steady fuel. This can make you feel tired, unfocused, irritable, or mentally foggy. To support better focus and mental clarity, aim for balanced meals that include protein, healthy fats, and fiber. Keeping your blood sugar stable is one of the simplest ways to reduce brain fog and boost energy naturally.

3. Poor sleep or inconsistent sleep patterns

Poor sleep or inconsistent sleep patterns can seriously mess with your mental clarity. When you’re not getting enough deep, restorative sleep, your brain doesn’t have time to detox, reset, or process information properly—which can leave you feeling foggy, forgetful, and unfocused the next day. Prioritizing quality sleep is key for reducing brain fog, boosting focus, and supporting your overall mental health.

4. Chronic stress and high cortisol levels

Chronic stress and high cortisol levels can leave your brain feeling wired but exhausted. When your body is constantly in fight-or-flight mode, it floods your system with stress hormones, which can disrupt memory, focus, and mental clarity. Over time, this can lead to burnout, fatigue, and serious brain fog. Supporting your nervous system through rest, blood sugar balance, and calming practices is essential for clearing the mental fog and feeling more grounded.

5. Hormonal changes

  • Cortisol (Stress Hormone): Chronic stress leads to elevated cortisol levels, which impair memory, focus, and sleep, worsening brain fog. Managing stress and sleep helps balance cortisol.
  • Estrogen: Low estrogen, common during perimenopause or menopause, can cause poor memory and concentration. Diet and natural supplements can support estrogen balance.
  • Progesterone: Low progesterone levels, often during the menstrual cycle or perimenopause, can lead to anxiety and cognitive issues. Stress management and balanced nutrition can help.
  • Thyroid Hormones (T3 & T4): Low thyroid function (hypothyroidism) slows brain processes, causing fatigue and brain fog. Supporting thyroid health through nutrients like iodine and selenium is key.
  • Insulin: Blood sugar imbalances, like insulin resistance, can lead to mental fog. Eating balanced meals stabilizes blood sugar, improving brain function.

6. Gut health issues (like leaky gut or dysbiosis)

Gut health is closely linked to brain function. Issues like leaky gut or dysbiosis can cause inflammation, which affects the brain, leading to brain fog. The gut also produces neurotransmitters like serotonin, which influence mood and focus. When the gut is out of balance, it can disrupt this process, resulting in poor mental clarity. Supporting gut health with a balanced diet, probiotics, and reducing inflammation can help clear brain fog and improve brain function.

7. Food sensitivities (e.g., gluten, dairy)

Food sensitivities can contribute to brain fog by triggering inflammation and immune responses in the body. When you consume foods that your body has trouble processing (like gluten, dairy, or certain additives), your immune system can react, causing inflammation in the gut and brain. This can lead to symptoms like brain fog, poor focus, and fatigue. Identifying and avoiding food triggers, along with supporting gut health, can help reduce inflammation and clear brain fog.

8. Chronic inflammation

Chronic inflammation can lead to brain fog by disrupting normal brain function. When the body is constantly inflamed, it releases pro-inflammatory chemicals that can reach the brain, impairing neurotransmitter activity and affecting cognition. This inflammation can come from factors like poor diet, stress, or chronic illness. Over time, this continuous inflammation can lead to symptoms like mental fatigue, poor concentration, and memory issues. Reducing inflammation through diet, exercise, and stress management can help clear brain fog and improve mental clarity.

Remember—you don’t need to tackle all of these at once! Go easy on yourself and explore these at your own pace until you find what works best for you.