By Mike Kocsis | 7 minutes read | Last updated: August 17, 2026 Categories: Hormone imbalance Testosterone
Medically Reviewed by Dr. George Touliatos
Brain fog, also known as mental fog, is a general term for a range of cognitive impairment symptoms, such as forgetfulness and slower thinking.
Nearly all men experience mental muddiness at some point in their lives due to lifestyle factors, including poor sleep and excessive screen time. However, some health problems like hormonal imbalance, diabetes, and autoimmune diseases can also cause it.
Brain fog is a temporary problem in most cases but if it persists, it may be a sign of an underlying health condition that needs medical attention.
What are the symptoms of brain fog?
Brain fog is subjective and can present differently from one person to another. People experiencing brain fog often report the following signs:
- Difficulty finding the right words
- Trouble holding conversations
- Absent-mindedness
- A sense of confusion
- Slower thinking
- Problem staying focused and difficulty concentrating
- Inability to retain new information
- Difficulty making decisions and plans
- Overwhelmed by simple routine tasks
- Mental fatigue and tiredness
- Impaired mental clarity
- Taking more time than usual to process information
What does brain fog feel like?
Brain fog can make you feel spaced out or like your brain has become ‘clouded.’
You go to a room and forget the reason. You unlock your phone to do something and then forget why you picked it up in the first place. You don’t remember what you ate yesterday or even for breakfast. During a conversation, you suddenly lose your train of thought.
You feel like your brain is running in slow motion. Things that once felt effortless now feel overwhelming.
What causes brain fog in men?
Brain fog in men may result from one or a combination of the following factors.
Lifestyle factors
Lack of sleep
Sleep deprivation is one of the leading causes of brain fog. Your brain needs time to get rid of mental clutter and recharge. When you don’t give it enough time to do so, it starts lagging and performing poorly.
Chronic stress
Prolonged exposure to stress hormones (cortisol) can interfere with cognitive function.
Smoking or vaping
Various studies show that vaping and smoking can negatively impact mental clarity, memory, and attention.
Drinking excessive alcohol
Heavy drinking can affect how brain chemicals work and can also lead to brain damage in men.
High screen time
Growing evidence suggests that prolonged screen time is associated with thinning of the cerebral cortex, a brain region responsible for memory, attention, and other cognitive functions.
Hormonal imbalances
Low testosterone
Research suggests that testosterone influences brain structure, neurotransmitter systems, and the activity of brain regions involved in memory, attention and cognition.
Men with low testosterone are more likely to report poor concentration, memory problems, mood changes, and reduced mental clarity.
Thyroid hormone issues
Both overactive and underactive thyroid disorders can impact focus, memory, and other cognitive functions in men.
Medical conditions
Mental cloudiness can be a symptom of some diseases, such as:
- Cancer
- Diabetes
- Hepatitis
- Kidney dysfunction
- HIV
- Long COVID-19
- Chronic fatigue syndrome
- Mental health conditions like anxiety and depression
- Sleep apnoea
- Chronic insomnia
- Autoimmune conditions (fibromyalgia, lupus, and multiple sclerosis)
- Neurodivergent conditions (ADHD and autism)
- Nutritional deficiencies (vitamin B12, vitamin D, iron)
Certain medications
Some medicines can also slow down brain activity and lead to brain fog. These include:
- Cancer treatment: Data reveals that around 75% of cancer survivors experience ‘chemo fog’ after chemotherapy.
- Pain relievers and sleep aids
- Anti-anxiety drugs
How to treat brain fog in men?
Temporary brain fog often goes away on its own with simple lifestyle habits. However, long-term brain fog, which is often the result of an underlying condition, may improve with the improvement of its root cause.
For instance, brain fog caused by vitamin B12 deficiency often improves after correcting the deficiency.
Similarly, if testosterone deficiency is making your brain foggy, restoring testosterone levels may help improve concentration, mental clarity, and overall cognitive function.
In short, there is no one-size-fits-all treatment for brain fog. You should work on pinpointing the source of the problem. Once it has been identified, the right treatment can be started.
Other practical tips to fix brain fog
Short-term brain fog can usually be cleared with simple habits that support brain function. Healthy habits that can help fix brain fog include:
- Get at least 7 hours of good quality sleep each night.
- Manage stress through meditation, yoga, breathing exercises, a walk in nature, and other relaxation techniques.
- Stay hydrated.
- Reduce your screen time. Replace it with reading, walking, or other offline activities.
- Simple cognitive strategies, such as using reminders and to-do lists, can make everyday tasks easier.
- Take short breaks between overwhelming tasks to prevent mental exhaustion and energy crashes.
- Avoid excessive caffeine consumption.
- Exercise regularly. Research shows regular exercise is linked to improved cognitive performance.
- Mental stimulation through puzzles or learning new skills may help keep your brain active.
How to diagnose brain fog caused by hormonal imbalance?
Hormone blood test is a common tool doctors use to determine if your brain fog symptoms are related to hormonal imbalance.
Your doctor will also consider your cognitive symptoms, medical history, and, if necessary, run more tests before making a diagnosis.
When to see a doctor
In most cases, brain fog lasts for a few hours to a few days and eventually improves on its own. But if it persists for weeks or longer and impacts different aspects of your daily life negatively, consult a healthcare provider.
Your doctor will evaluate your symptoms and overall health to make a diagnosis and prescribe a suitable treatment plan.
Final thoughts
Men can experience brain fog due to inconsistent sleep, low testosterone levels, high stress levels, low blood sugar levels, autoimmune disorders, and medications.
Brain fog can make your mind feel clouded, confused, slower, and exhausted. While experiencing it once in a blue moon is common but if it persists longer than usual or keeps coming back, you should discuss the matter with your physician. Persistent brain fog is usually a sign of an underlying problem that requires attention.
Low testosterone levels in men can disrupt memory, concentration, and other similar cognitive abilities. Restoring testosterone levels through hormone therapy may assist getting rid of associated symptoms.
Contact us today to discuss your testosterone hormone-related concerns and find reliable solutions.
References
Denno, P., Zhao, S., Husain, M. and Hampshire, A., 2025. Defining brain fog across medical conditions. Trends in Neurosciences, 48(5), pp.330-348.
Haywood, D., Rossell, S.L. and Hart, N.H., 2025. Cutting through the fog: recognising brain fog as a significant public health concern. BMC Public Health, 25(1), p.1230.
Yeap, B.B. and Flicker, L., 2022. Testosterone, cognitive decline and dementia in ageing men. Reviews in Endocrine and Metabolic Disorders, 23(6), pp.1243-1257.
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About the Author: Mike Kocsis
Mike Kocsis has an MBA with a focus on healthcare administration and is an entrepreneur and medical case manager for Balance My Hormones which offers medical services in the UK and Europe. Mike has over 25 years of experience in the healthcare sector, much of that working with people who have hormone imbalances. Mike has appeared on podcasts and radio and is an expert speaker on the subject of hormone imbalance. He specialises in Testosterone Replacement Therapy and Hormone Replacement Therapy (HRT) and with his first-hand experience he has helped thousands of people suffering from low testosterone recover and regain control of their lives. You can follow him on LinkedIn and on the Balance My Hormones YouTube Channel.
Last update: August 17th, 2026
