Hashimoto’s disease, also known as chronic lymphocytic thyroiditis, is an autoimmune disorder that causes the immune system to attack and damage the thyroid gland. This leads to hypothyroidism, or an underactive thyroid, which means the thyroid doesn’t produce enough thyroid hormones. Hashimoto’s is the most common cause of hypothyroidism in the United States.
One of the most common symptoms reported by people with Hashimoto’s is brain fog, which refers to problems with focus, memory, mental clarity, and concentration. But what causes brain fog in Hashimoto’s disease, and is there a link between Hashimoto’s and brain fog? Here is an in-depth look at the evidence.
What is Brain Fog?
Brain fog is not a medical term, but rather a shorthand way to describe cognitive dysfunction and decreased mental sharpness. People experiencing brain fog may have these kinds of symptoms:
- Forgetfulness
- Difficulty focusing and paying attention
- Problems recalling words or memories
- Processing information more slowly
- Feeling confused, like your brain is in a fog
- Having trouble learning new things
- Struggling with decision-making
- Taking longer to do routine tasks
Brain fog can range from mild to severe, and it tends to fluctuate day to day or week to week in many people. For some, brain fog comes and goes, while for others it feels like a constant state. Even mild brain fog can negatively impact work performance, relationships, and quality of life.
What Causes Brain Fog in Hashimoto’s?
There are several possible reasons why Hashimoto’s and brain fog often go hand-in-hand:
Thyroid Hormone Imbalance
Thyroid hormones play an important role in regulating metabolism, mood, heart rate, body temperature, and brain function. When Hashimoto’s damages the thyroid so that it underproduces hormones, the resulting hypothyroidism can impair brain processes and lead to cognitive dysfunction.
Many studies have found links between hypothyroidism and decreased mental sharpness, impaired memory, reduced processing speed, and other hallmarks of brain fog. Treating the hypothyroidism with thyroid hormone replacement medication often resolves these cognitive issues.
Hashimoto’s Encephalopathy
In rare cases, Hashimoto’s can trigger an autoimmune reaction directly affecting the brain. This is known as Hashimoto’s encephalopathy or “brain fog.” Symptoms may include cognitive impairment, hallucinations, stroke-like episodes, and others. It is not caused by thyroid problems and is treated with steroids instead of thyroid medication.
Inflammation
Chronic inflammation appears to play a role in many autoimmune diseases, including Hashimoto’s. Researchers have found elevated inflammatory markers in the blood of Hashimoto’s patients.
There is also some evidence linking inflammation to brain fog symptoms. Inflammation may have effects on areas like the hippocampus, which is involved in memory. More research is needed on how inflammation may contribute to brain fog in Hashimoto’s.
Other Autoantibodies
In addition to attacking thyroid peroxidase and thyroglobulin, some Hashimoto’s patients develop other autoantibodies that could potentially impact brain function. These include antinuclear antibodies (ANA), antineuronal antibodies, and glutamic acid decarboxylase (GAD) antibodies.
More research is needed, but in theory these autoantibodies could interfere with neurotransmission or brain processes and lead to some cognitive symptoms.
Other Nutrient Deficiencies
A hypothyroid state can lead to impaired absorption of important nutrients like iron, vitamin B12, and vitamin D. Deficiencies in these nutrients are associated with some neurological symptoms and cognitive deficits.
Ensuring adequate intake of key nutrients may help improve brain fog, especially if labs show any deficiencies. Many Hashimoto’s patients are found to be low in vitamin D, for example.
Depression and Anxiety
Hashimoto’s patients have higher rates of depression and anxiety disorders compared to the general public. Cognitive dysfunction and memory problems are common symptoms of depression. The brain fog associated with depression likely involves some overlapping biological mechanisms as brain fog in Hashimoto’s disease itself.
Sleep Disturbances
Hypothyroidism and Hashimoto’s flare-ups can disrupt normal sleep patterns and lead to unrestful sleep. Lack of quality sleep has major effects on cognitive function the next day. Optimizing sleep and rest through stress reduction, medication if needed, and good sleep hygiene can help improve brain fog.
Medications
Some medications used to treat other Hashimoto’s symptoms may potentially contribute to brain fog as a side effect. These include opioids for pain, benzodiazepines for anxiety, anticonvulsants, and others. Look at medication side effects if brain fog seems worse.
Are There Links Between Hashimoto’s and Dementia?
There has been some research investigating whether there could be any association between Hashimoto’s thyroiditis and increased risk of dementia or Alzheimer’s disease later in life.
A few small studies have found higher rates of thyroid autoantibodies and hypothyroidism in patients with Alzheimer’s disease. However, most research has not found clear evidence that Hashimoto’s itself is linked to dementia. Having well-treated hypothyroidism does not appear to increase dementia risk.
More research is still needed on this potential connection. As of now, there are no definite links between Hashimoto’s disease and dementia according to most experts.
Tips to Improve Hashimoto’s Brain Fog
While more studies are still needed, there are some steps Hashimoto’s patients can take now to help reduce brain fog symptoms:
- Get thyroid levels tested regularly and take thyroid medication as prescribed to keep TSH and hormone levels optimal.
- Discuss any significant brain fog with your doctor to rule out rare causes like Hashimoto’s encephalopathy.
- Reduce inflammation through diet, stress management, exercise, and anti-inflammatory supplements like turmeric or omega-3s.
- Have any other autoantibodies or nutrient levels checked and address any issues found.
- Consider eliminating gluten, dairy, or other trigger foods to see if this helps.
- Optimize sleep and treat any sleep disorders present.
- Use apps, lists, calendars, and reminders as cognitive aids when needed.
- Incorporate brain-stimulating activities into your day, like reading, puzzles, crafts, or learning a new skill.
- Practice stress-reducing techniques, like yoga, meditation, or breathing exercises.
While not definitive, early research also suggests potential benefits from:`
- Omega-3 fatty acids
- Probiotics
- Curcumin
- B vitamins
- Zinc
- SAMe (S-Adenosyl methionine)
- N-Acetyl cysteine (NAC)
- Alpha lipoic acid
- CoQ10
- Creatine
Always check with your doctor before starting any new supplements, especially if you are already taking medications.
The Bottom Line
Brain fog is a commonly reported symptom among Hashimoto’s patients. Imbalanced thyroid hormone levels, inflammation, autoantibodies, poor sleep, nutrient deficiencies, and depression are possible contributors research has linked to brain fog.
While brain fog can significantly lower quality of life, the good news is there are many potential ways to help reduce those symptoms through thyroid medication, diet, lifestyle factors, supplements, and more. Work closely with your healthcare providers to find the best treatment approach for your individual case. Be patient, as it may take some time to find what works for you.
Tables Summarizing Key Points
Table 1. Common Brain Fog Symptoms
| Memory problems | Difficulty concentrating |
|---|---|
| Slowed thinking | Trouble learning new things |
| Poor focus | Reduced mental clarity |
| Impaired recall | Harder decision making |
| Feeling confused | Taking longer on routine tasks |
Table 2. Possible Causes of Brain Fog in Hashimoto’s
| Hypothyroidism | Hashimoto’s encephalopathy (rare) |
|---|---|
| Inflammation | Other autoantibodies |
| Nutrient deficiencies | Depression or anxiety |
| Sleep disturbances | Side effects of medications |
Table 3. Tips to Help Reduce Brain Fog
| Optimize thyroid hormone levels | Reduce inflammation |
|---|---|
| Check for autoantibodies and nutrients | Eliminate trigger foods |
| Improve sleep habits | Use cognitive aids and tools |
| Incorporate brain exercises | Manage stress |
| Consider supplements like omega-3s | Work closely with your healthcare team |
Conclusion
In summary, brain fog is a complex but common symptom in Hashimoto’s patients that can significantly disrupt quality of life. While more research is still emerging, the good news is that a multifaceted approach can help reduce brain fog for many people with Hashimoto’s. Work closely with knowledgeable healthcare providers to find the optimal treatment plan for your individual case. With patience and consistent effort, significant improvements in brain fog are possible in order to help you feel mentally sharp and fully engaged in life once again.