Depression and the Physical Toll of Fatigue on the Body


Depression is a mental illness that affects millions of people worldwide. While the symptoms of depression are primarily emotional and cognitive, many people with depression also experience physical symptoms. One of the most common physical symptoms of depression is fatigue, which can take a significant toll on the body. In this article, we will explore the relationship between depression and fatigue, and how the physical toll of fatigue can affect the body.

The Link Between Depression and Fatigue

Fatigue is a common symptom of depression, affecting up to 90% of people with the illness. Fatigue can manifest in different ways, ranging from a lack of energy to physical tiredness and lethargy. The reasons for fatigue in depression are not entirely clear, but several factors are thought to contribute to this symptom.


Neurotransmitters are chemicals in the brain that regulate mood, behavior, and other essential functions. In people with depression, the neurotransmitter levels are often imbalanced, leading to changes in mood, energy levels, and physical symptoms. The neurotransmitter serotonin, for example, is closely linked to mood and fatigue, and a deficiency in this chemical can contribute to feelings of lethargy and tiredness.

Sleep Disturbances

Sleep disturbances are another common symptom of depression, with up to 80% of people with depression experiencing sleep problems. Insomnia, which is the inability to fall or stay asleep, is a prevalent sleep problem in depression. Sleep deprivation can lead to physical fatigue in the short term and has several long-term effects on the body.


Dealing with depression can be incredibly stressful, and stress can take a significant toll on the body. When the body experiences stress, it produces cortisol, a stress hormone that is linked to fatigue. High levels of cortisol in the body are thought to contribute to the physical fatigue commonly experienced by people with depression.

The Physical Toll of Fatigue on the Body

Fatigue can take a significant toll on the body, and people with depression are particularly vulnerable to this. Here are some of the ways that fatigue can impact the body in people with depression:

Immune System

The immune system plays a crucial role in keeping the body healthy, fighting off infections and diseases. However, fatigue can impair the immune system's function, making the body more susceptible to illness and infection. People with depression who experience physical fatigue may be at an increased risk of developing illnesses and infections due to the immune system's impairment.

Cardiovascular System

Fatigue can also have significant impacts on the cardiovascular system. Fatigue can make it difficult to engage in physical activity, which can lead to weight gain and an increased risk of heart disease. Additionally, fatigue can cause the heart to work harder to pump blood throughout the body, leading to an increased workload on the cardiovascular system.

Endocrine System

The endocrine system is responsible for hormone production and regulation, among other things. Fatigue can disrupt the endocrine system's function, leading to significant hormonal imbalances that can have a range of negative effects on the body. For example, fatigue can lead to imbalances in cortisol, insulin, and growth hormone levels, all of which can have significant health consequences.


The link between depression and fatigue is complex, with several factors thought to contribute to this common symptom. Fatigue can take a significant toll on the body, impacting the immune system, cardiovascular system, and endocrine system. It is crucial for people with depression who experience physical fatigue to seek appropriate medical care to address this symptom's underlying causes and mitigate the potential long-term effects on the body.