A lack of sleep, poor diet, anxiety or stress can often cause a person to feel sick. However, it could also be a sign of pregnancy or chronic illness.

When sick, a person may experience stomach discomfort and vomiting. The medical term for this is nausea.

In this article, we look at the causes, symptoms, and treatments for a person feeling sick all the time.

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A person may feel sick due to a short-term issue or as a result of a chronic condition. According to the Centers for Disease Control and Prevention (CDC), as of 2019, around 60% of American adults had at least one chronic or long-term condition, and 40% had two or more.

Below are some common reasons why someone might feel sick, plus their symptoms and how to treat each one.

Infection

Bacterial, viral, and fungal infections can all cause a person to feel sick. Food poisoning is a common reason that a person may feel sick.

However, infections can also spread through other means. People may be more at risk of catching an infection if they:

  • work with children
  • work in the healthcare industry
  • live in close quarters with other people, such as in dormitories
  • travel a lot or use public transportation frequently

Learn more about the types of infection here.

Treatment

Infections such as food poisoning will typically resolve independently with rest. If someone experiences vomiting or diarrhea due to infection, they must ensure they drink plenty of fluids.

A person can reduce their risk of infection through

  • proper food preparation and storage
  • frequent handwashing
  • covering the face when close to someone with a contagious illness
  • using hand sanitizers

Digestive disorders

Many common digestive disorders can cause a person to feel sick. These include:

Learn more about common digestive disorders here.

Treatment

The treatment of common digestive disorders will vary depending on the cause. However, most treatment plans will include a combination of lifestyle modifications and medication.

Immune conditions

Autoimmune conditions weaken the immune system and make it easier to develop infections, colds, and flu. People with chronic immune conditions tend to feel sick more often and may take longer to recover from illnesses. More than 23.5 million Americans live with an autoimmune condition.

Common immune conditions that can make people feel sick include:

Autoimmune conditions cause many symptoms, including fatigue, rashes, insomnia, and gastrointestinal problems.

Discover more about autoimmune conditions.

Treatment

The only way to treat symptoms related to an autoimmune condition is to seek medical treatment and monitoring for the condition.

Anxiety

Many people may not associate anxiety with feeling sick, but often it can make a person feel sick to their stomach.

A person with anxiety may feel nauseous or find that they get sick more often because their anxiety weakens their immune responses.

Other symptoms of anxiety include:

It is natural for people to experience anxiety. When a person feels anxious continuously, and this gets in the way of daily life, they may wish to talk with a doctor about anxiety disorders.

If a person feels anxiety on most days for 6 months or more, a doctor may diagnose them with generalized anxiety disorder (GAD).

A person may have a specific anxiety disorder or a phobia if their anxiety is specific to certain situations, such as social contact or unhygienic places.

Learn more about the types of anxiety and their symptoms here.

Treatment

Anxiety and anxiety disorders are treatable. Possible options include:

Discover more treatments for anxiety here.

Chronic stress

Stress is a natural response to a perceived threat. However, continual stress can affect the mind and body.

People with chronic or extreme stress can have many different symptoms, as stress affects the immune system, nervous system, hormones, and heart functioning.

Other symptoms of chronic stress can include:

Discover more about chronic stress here.

Treatment

Treatment will start with identifying what stressors are causing the condition. From here, a person may be able to take steps to reduce the influence of these stressors. However, not all causes of stress are within a person’s control.

If possible, people may be able to reduce their exposure to stressors. However, this is not always possible. Psychotherapy, such as cognitive behavioral therapy (CBT), can help people manage their response to stressors.

Many traditional and alternative therapies exist to help manage or alleviate stress.

  • resolving sources of conflict
  • regular exercise
  • practicing exercises for mindfulness and stress release, such as yoga
  • seeking support

Learn more about stress management here.

Lack of sleep

Proper, regular sleep is important for mental and physical health. Sleep deprivation can increase a person’s risk of developing physical and mental health problems.

Common symptoms of chronic sleep deprivation, or a lack of adequate sleep, include:

Treatment

Common ways to improve sleep deprivation include:

  • develop a regular sleep schedule
  • remove any sources of distraction from the bedroom
  • treat conditions that hinder sleep, such as sleep apnea, restless leg syndrome, and anxiety
  • limit caffeine intake

Why is sleep so important for good health? Learn more here.

Poor diet and dehydration

Dehydration and malnutrition or having a poor diet, put stress on the body. A chronic lack of proper nutrients and hydration can cause many problems, including:

  • feeling sick
  • vomiting
  • chronic fatigue and weakness
  • dizziness or light-headedness
  • difficulty concentrating
  • poor immune health and extended healing time
  • weight loss

Treatment

There is no single amount of plain water a person should drink daily. Recommendations for daily water intake differ depending on a person’s age, sex, pregnancy status, and illness. However, some health professionals recommend around 6-8 glasses of water per day.

If a person feels persistently dehydrated despite adequate fluid intake, they should visit their doctor

To treat and prevent malnutrition, people should eat a balanced diet rich in various nutrient-dense foods.

Alcohol, caffeine, drugs, or medications

Alcohol, caffeine, recreational drugs, and many prescription medications can affect a person’s physical health.

For example, some anticancer drugs cause sickness, and alcohol consumption can affect sleep and cause gastrointestinal diseases.

Treatment

If a prescription medication is causing a person to feel sick, they should speak with their doctor to discuss alternatives or supplementary treatments.

In cases of caffeine, alcohol, and recreational drug use, reducing consumption or abstinence can often improve symptoms.

Learn more about detoxing from alcohol here.

Seeking help for addiction may seem daunting or even scary, but several organizations can provide support. If you believe that you or someone close to you is struggling with addiction, you can contact the following organizations for immediate help and advice:

Pregnancy

During pregnancy, a person may feel sick due to morning sickness. Despite its name, this can occur at any time of the day.

Learn more in our dedicated pregnancy and parenthood hub here.

People who always feel sick are more likely to have to skip work or school, or they may be less able to perform day-to-day activities. This is especially true when a person has a chronic condition.

Chronic conditions can also cause anxiety and interfere with activities that are important to good health, such as proper sleep, exercise, and socializing.

Though the specific complications depend on the cause, a person who feels sick all the time and whose symptoms do not improve may develop depression, anxiety, or fatigue.

Anyone who feels sick for more than a week or two should seek medical attention. A doctor can figure out the cause of the sickness and provide treatment.

A doctor may also recommend lifestyle changes or therapies that can reduce symptoms.

Talking with a doctor about prolonged sickness is also important so they can rule out or treat underlying medical conditions.

It is common for people to feel sick, and it is not a cause for concern. Symptoms are often self-limiting and may resolve independently or with minor home treatments.

However, feeling sick continuously can signal an underlying health condition. Treating these conditions will often resolve sickness symptoms.

People may feel sick due to medical conditions, environmental factors or unhealthy habits

Rest, adequate hydration, and dietary changes can treat many short-term causes of sickness. However, when symptoms result from a chronic condition, treating the underlying cause is necessary to resolve symptoms.