Always tired and forgetful? It may not just be work stress, doctors explain why

You open an email and forget why you clicked it. You reread the same paragraph three times but still struggle to focus. Or perhaps you find yourself zoning out during meetings and struggling to complete tasks that once felt routine.

Many working professionals dismiss these lapses as stress or lack of sleep. But experts say persistent brain fog, forgetfulness and mental fatigue could be linked to something deeper, from poor nutrition and chronic stress to underlying health conditions.

Brain fog is not a medical diagnosis, but a term commonly used to describe symptoms such as forgetfulness, difficulty concentrating, mental fatigue and slowed thinking.

WHY YOUR FOOD CHOICES MATTER

According to Dr Padmini B V, Nutrition and Dietician at Apollo Hospitals, Seshadripuram, Bengaluru, unhealthy food habits have become one of the major contributors to mental fatigue and poor concentration among working professionals.

The main causes include unhealthy eating habits, skipping breakfast, eating late dinners and relying on convenient food options during a busy work schedule.

Dr Padmini stressed that not only what people eat but also when and how they eat plays a crucial role in maintaining mental well-being.

She explained that the gut and the brain constantly communicate through a network known as the gut-brain axis. When poor dietary habits disrupt the balance of healthy gut bacteria, that communication can be affected, potentially contributing to mental fatigue and difficulty concentrating.

When diets are dominated by processed foods, excess sugar and high-fat meals, the balance of beneficial gut bacteria can be disrupted. This condition, known as gut dysbiosis, may affect the gut-brain connection and contribute to symptoms such as brain fog and mental exhaustion.

“The vagus nerve helps maintain communication between the gut and the brain, and poor dietary habits may negatively affect this pathway, contributing to mental fatigue,” she explained.

WHEN BRAIN FOG COULD SIGNAL SOMETHING MORE SERIOUS

However, experts caution that not every case of brain fog can be explained by stress or unhealthy eating habits alone.

Dr Srinivas M, Consultant Neurologist at Apollo Hospitals, Seshadripuram, Bengaluru, said that while temporary lapses in concentration are often linked to stress, inadequate sleep or exhaustion, symptoms that persist despite lifestyle changes may require medical attention.

"If poor concentration and forgetfulness continue even after improving sleep, nutrition and physical activity, it could indicate an underlying neurological, psychiatric or systemic condition," he said.

According to Dr Srinivas, warning signs include progressive memory loss, difficulty finding words during conversations, trouble learning new skills, challenges in performing multiple tasks, difficulty navigating familiar or unfamiliar routes, persistent headaches, tremors, weakness or balance problems.

These symptoms, particularly when accompanied by ongoing brain fog, should not be dismissed as routine stress.

THE HIDDEN MEDICAL CAUSES BEHIND MENTAL FATIGUE

Brain fog is rarely caused by a single factor.

Neurologists say a wide range of health conditions can affect cognitive performance and mental clarity. These include inadequately treated migraine, epilepsy, multiple sclerosis, autoimmune disorders and early neurodegenerative diseases.

Nutritional deficiencies are also common culprits. Low levels of vitamin B12, vitamin D and iron can affect concentration, memory and energy levels. Conditions such as thyroid disorders, kidney disease and anaemia can produce similar symptoms.

Chronic inflammation within the body may also contribute to cognitive difficulties. Experts point to obesity, sleep apnoea, insomnia, smoking, alcohol use and even excessive screen dependence as factors that can affect brain function over time.

Dr Srinivas added that addressing brain fog often requires a personalised approach that goes beyond medication and includes lifestyle modifications, nutritional support and family involvement.

He also highlighted growing concerns around neurodegenerative diseases such as Alzheimer's disease, stressing the importance of addressing modifiable risk factors including nutrition, sleep and overall health.

BRAIN FOG OR BURNOUT? HERE'S HOW TO TELL THE DIFFERENCE

One reason brain fog often goes unnoticed is because its symptoms closely resemble burnout. Poor concentration, forgetfulness and mental exhaustion can occur in both conditions, making it difficult for people to identify the root cause.

Dr Sugami Ramesh, Clinical Psychologist at Apollo Hospitals, Bannerghatta Road, Bengaluru, said that many people experiencing burnout are often aware that they are neglecting basic self-care.

"Lack of sleep, poor self-care and unhealthy lifestyle patterns often create feelings of guilt and contribute to chronic stress and burnout," she said.

While the two conditions can overlap and only a healthcare professional can determine the underlying cause, experts say there are some general patterns that may help distinguish them.

Brain fog is more likely when:

• Symptoms fluctuate throughout the day.
• Poor sleep, irregular meals or unhealthy eating habits are present.
• Nutritional deficiencies or underlying health conditions may be involved.
• People describe feeling mentally "slowed down" or unable to think clearly.

Burnout is more likely when:

• Emotional exhaustion is persistent.
• Work feels overwhelming even after a break.
• Motivation, productivity and engagement gradually decline.
• Feelings of cynicism, frustration or detachment from work become common.

"Quality sleep plays a critical role in memory, emotional regulation, decision-making and metabolic health. It is not simply rest, it is the body's biological recovery process," she explained.

When sleep becomes inadequate, the brain's prefrontal cortex – the region responsible for focus, judgement and impulse control – becomes less efficient. At the same time, stress hormones such as cortisol remain elevated, making it harder to think clearly and manage emotions.

WHAT CAN HELP IMPROVE MENTAL CLARITY?

While there is no single solution for brain fog, experts agree that small lifestyle changes can have a significant impact.

Dr Sugami recommends:

• Following a consistent sleep schedule by going to bed and waking up at the same time every day.
• Limiting caffeine and alcohol intake, particularly in the evening.
• Prioritising balanced nutrition.
• Reducing excessive screen time.
• Incorporating regular physical activity.
• Practising stress-management techniques such as mindfulness, deep breathing and journaling.

Dr Padmini also advises increasing intake of nutrient-rich foods that support brain and gut health. These include vegetables, fruits, nuts, seeds, eggs, fish and fermented foods such as curd.

Foods rich in vitamins A, B, C and D, along with sources of healthy fats like walnuts, flaxseeds and pumpkin seeds, may help support cognitive function and maintain a healthier gut-brain connection.

WHEN SHOULD YOU PAY ATTENTION?

Feeling mentally drained sometimes is normal. But if forgetfulness, poor concentration and mental fatigue become persistent, they may be signalling something more than workplace stress.

Experts say that improving sleep, nutrition and physical activity can often make a noticeable difference. However, when symptoms continue despite these changes, seeking medical advice is important to rule out underlying neurological, psychological or metabolic conditions.

Experts say persistent brain fog should not be dismissed as an inevitable part of modern work life. While occasional lapses in focus are normal, persistent forgetfulness, mental fatigue and difficulty concentrating may be your body's way of signalling that something needs attention – whether it's your diet, sleep, stress levels or an underlying health condition.