What is the cause of body aches and tiredness?

September 22, 2025 •

5 min read

Experts agree that persistent body aches and tiredness can stem from a wide range of factors, both temporary and chronic. Understanding what is the cause of body aches and tiredness is the first step toward effective relief and management of your symptoms.

Quick Summary

Body aches and tiredness can be caused by infections, lack of sleep, dehydration, stress, or underlying chronic conditions like fibromyalgia or anemia. Identifying the root cause is essential for a proper diagnosis and effective treatment plan.

Key Points

Infections Cause Inflammation: Viral illnesses like the flu, common cold, and COVID-19 can cause widespread inflammation and muscle soreness as your immune system fights the infection.
Everyday Factors Have a Big Impact: Lack of sleep, dehydration, stress, and overexertion are frequent and simple causes of general achiness and fatigue.
Chronic Illnesses are a Possibility: Persistent, unexplained body pain and exhaustion could signal an underlying condition such as fibromyalgia, chronic fatigue syndrome, or an autoimmune disease.
Nutrient Deficiencies Matter: Inadequate levels of vitamins and minerals, particularly Vitamin D and iron, can negatively affect muscle function and energy production.
Seek Medical Advice for Persistent Symptoms: If your symptoms are severe, last for more than a week, or are accompanied by other concerning signs, it's time to consult a doctor to rule out more serious issues.
Medications Can Be a Factor: Some prescription medications can list body aches and tiredness as side effects, so consider if new medicine coincides with your symptoms.

Common and Everyday Causes

Even with a healthy lifestyle, feelings of achiness and fatigue can arise from everyday issues. Often, these are temporary and resolve with simple self-care.

Dehydration

Water is essential for every bodily function, including lubrication of joints and proper muscle function. When you don't drink enough fluids, your body can't function at its peak, leading to muscle cramps, soreness, and a general feeling of malaise. Drinking plenty of water, especially in hot weather or during physical activity, is a crucial step for preventing these symptoms.

Sleep Deprivation

Adequate rest is vital for the body's repair and recovery processes. During deep sleep, the body releases hormones that repair damaged tissue and regenerate cells. A lack of quality sleep interferes with this process, making you more sensitive to pain and leading to persistent tiredness. Sleep deficiency can also worsen existing pain and contribute to inflammation.

Stress and Anxiety

Emotional stress can manifest as physical symptoms. When under stress, the body releases stress hormones that cause muscles to tense up. Prolonged muscle tension can result in generalized body aches, especially in the neck, shoulders, and back. The mental and emotional strain of stress can also be physically exhausting, contributing significantly to a feeling of tiredness.

Overexertion or Overtraining

Intense or new physical activity can cause microscopic tears in muscle fibers. This is a normal part of building muscle, but it also triggers inflammation and soreness that can last for several days. Without proper rest between workouts, your body doesn't have time to recover, leading to a state of constant tiredness and achiness.

Viral and Bacterial Infections

Many common infections trigger a full-body response from your immune system, which can result in aches and fatigue as your body fights off the invading pathogens.

The Flu and Common Cold

Influenza is a classic example of an illness that causes sudden and intense body aches, fever, and chills. Your immune system's inflammatory response to the virus is responsible for this widespread soreness. While milder, the common cold can also cause similar, though less severe, symptoms.

Mononucleosis

Often called "mono," this viral infection is notorious for causing extreme fatigue, body aches, sore throat, and swollen lymph nodes. The Epstein-Barr virus is typically responsible, and the debilitating tiredness can last for weeks or even months.

COVID-19

Infections with the COVID-19 virus often include body aches and severe fatigue as key symptoms. The body's inflammatory response can be widespread, causing muscle soreness and profound exhaustion that can linger even after the main illness has passed.

Chronic Conditions and Diseases

If your body aches and tiredness are persistent and have no clear cause, they may be a symptom of an underlying chronic health condition. Diagnosis and management of these conditions typically require medical intervention.

Fibromyalgia

Fibromyalgia is a chronic disorder characterized by widespread musculoskeletal pain, fatigue, and cognitive difficulties (often called "fibro fog"). The condition is believed to involve the way the brain processes pain signals, amplifying painful sensations.

Chronic Fatigue Syndrome (CFS)

Also known as myalgic encephalomyelitis (ME), CFS causes debilitating fatigue that is not relieved by rest and is often accompanied by muscle and joint pain. The exhaustion is so severe it can interfere with daily life.

Autoimmune Disorders

Conditions where the immune system mistakenly attacks healthy tissue, such as lupus or rheumatoid arthritis, can cause systemic inflammation. This widespread inflammation often leads to chronic joint pain, stiffness, and fatigue.

Thyroid Disorders

An underactive thyroid, or hypothyroidism, can cause a wide range of symptoms, including fatigue, muscle aches, and weakness. The thyroid gland regulates metabolism, so its underperformance can slow down various bodily functions.

Anemia

This condition occurs when your body doesn't have enough healthy red blood cells to carry oxygen to your tissues. Low oxygen levels can cause weakness, fatigue, and pain, as muscles and organs struggle to function properly.

Other Potential Factors

Beyond infections and chronic diseases, other factors can play a role in causing body aches and tiredness.

Side Effects from Medications

Certain medications, including some statins (cholesterol-lowering drugs) and blood pressure medications, can cause muscle soreness and fatigue as a side effect. If you've recently started a new medication and noticed these symptoms, it's best to consult your doctor.

Vitamin and Mineral Deficiencies

Nutritional deficiencies can impact muscle and joint health. A lack of Vitamin D, for example, can lead to bone and muscle pain. Insufficient potassium or magnesium levels can also cause muscle cramping and weakness.

Comparison of Common Causes


Feature	Common Cold	The Flu	Fibromyalgia	Sleep Deprivation
Onset	Gradual	Sudden	Gradual / Unpredictable	Gradual
Symptom Severity	Mild to moderate	Moderate to severe	Moderate to severe	Mild to severe
Duration	7-10 days	1-2 weeks	Chronic (long-term)	Chronic (as long as sleep is poor)
Aches	Present, but mild	Prominent and severe	Widespread, persistent	Can be mild to moderate
Fatigue	Mild to moderate	Prominent and severe	Debilitating	Prominent
Fever	Rare	Common	No	No
Best Treatment	Rest, fluids	Antivirals, rest, fluids	Symptom management, exercise	Improve sleep hygiene

When to See a Doctor

While many cases of body aches and tiredness resolve on their own, certain signs warrant medical attention. You should see a healthcare provider if:

Your symptoms are severe or significantly interfere with your daily life.
Symptoms persist for more than a week without improvement.
You develop a high fever, difficulty breathing, or severe pain.
You experience unexplained weight loss.
You suspect a chronic condition or your symptoms are recurring.

For more information on general fatigue, you can visit the Healthline article on the topic: Healthline: Fatigue: Causes, Diagnosis, Treatment & More.

Conclusion: Taking Control of Your Health

Body aches and tiredness are common and can have numerous underlying causes, ranging from simple lifestyle factors to more serious chronic illnesses. While rest and hydration can resolve many mild cases, it's important to listen to your body. Paying attention to other symptoms and their duration can help you determine the root cause. If your symptoms are concerning or persistent, consulting a healthcare professional is the best way to get an accurate diagnosis and find the most effective treatment for relief.

Frequently Asked Questions

Yes, chronic stress can lead to muscle tension, which manifests as body aches, especially in the neck and shoulders. The mental and emotional strain also drains your energy, causing significant tiredness.

Dehydration can lead to muscle cramps and soreness because water is crucial for proper muscle function. Insufficient fluid intake can prevent muscles from working efficiently and lead to general aches.

Yes, it is common to experience mild body aches with a cold or the flu. The body's immune system releases chemicals to fight the infection, which can cause widespread inflammation and soreness.

Normal tiredness is typically relieved by rest. Chronic fatigue syndrome (CFS) involves severe, persistent exhaustion that is not resolved by sleep and significantly impacts your daily life and activities.

Yes, deficiencies in essential nutrients like Vitamin D and iron (which can cause anemia) are known to cause muscle pain and fatigue. A blood test can determine if a deficiency is the underlying issue.

You should see a doctor if your symptoms are severe, persist for more than a week, or are accompanied by other worrying signs like a high fever, severe swelling, or difficulty breathing.

Yes, some medications, such as statins and certain blood pressure medications, can list body aches and fatigue as potential side effects. Always consult your doctor if you suspect a medication is the cause.

Yes, both fibromyalgia and Chronic Fatigue Syndrome are characterized by persistent, widespread body aches and debilitating fatigue. These conditions require professional medical management.