Stress is your body’s response to an actual or perceived threat. Some stress is good for you and drives you to take action, like looking for a job when you’ve been fired. Too much stress, however, can suppress your immune system and cause you to get sick more easily.

Prolonged periods of stress can also increase your risk of several diseases, including heart disease and cancer. According to a study, 60 to 80 percent of doctor’s office visits may be stress-related.

Stress can cause a number of physical symptoms and illnesses. Symptoms can come on as soon as your level of stress increases and worsen as stress continues. These symptoms usually go away once your stress level lowers.

Some of the symptoms commonly caused by stress include:

  • increased heart rate
  • increased blood pressure
  • rapid breathing
  • shortness of breath
  • muscle tension
  • headache
  • nausea
  • dizziness

If your stress levels remain high or you experience frequent stress, your risk of getting sick increases.

Fever

Chronic stress and exposure to emotional events can cause a psychogenic fever. This means the fever is caused by psychological factors instead of a virus or other type of inflammatory cause. In some people, chronic stress causes a persistent low-grade fever between 99 and 100˚F (37 to 38°C). Other people experience a spike in body temperature that can reach as high as 106˚F (41°C) when they’re exposed to an emotional event.

Psychogenic fever can happen to anyone under stress, but it most commonly affects young women.

The common cold

A 2012 study found that chronic psychological stress prevents the body from properly regulating the inflammatory response. Inflammation has been linked to the development and progression of many diseases. People who are exposed to long periods of stress are more likely to develop colds upon exposure to the cold-causing germs.

Stomach issues

Evidence shows that stress stops your gastrointestinal system from working properly, affecting your stomach and large bowel. Stress can cause a wide range of gastrointestinal symptoms, including:

  • abdominal pain
  • nausea
  • indigestion
  • diarrhea
  • constipation

Stress has also been shown to aggravate the symptoms of irritable bowel syndrome (IBS), and it may be one of the main causes of IBS. If you suffer from stomach acid reflux with heartburn, stress can worsen your symptoms by increasing your sensitivity to stomach acid. If not well-controlled, inflammation from stomach acid erosion raises your risk of peptic ulcers. Chronic diarrhea or constipation can lead to conditions such as hemorrhoids.

Depression

Research has linked both chronic stress and shorter periods of acute stress to depression. Stress throws several of your brain chemicals out of balance, including serotonin, dopamine, and norepinephrine. It also elevates your cortisol level. All of these are linked to depression. When this type of chemical imbalance occurs, it negatively affects your:

  • mood
  • sleep pattern
  • appetite
  • sex drive

Headaches and migraines

Stress is a common trigger of headaches, including tension and migraine headaches. One study found that relaxing after experiencing a period of stress can lead to an acute migraine headache episode within the next 24 hours. This is thought to be caused by what’s known as the “let-down” effect. The study concluded that medication or behavioral modification could help prevent headaches for those who have migraines related to stress reduction.

Allergies and asthma

Life stress has been linked to the onset and worsening of mast cell-associated diseases, including asthma and allergies. Histamine causes allergy symptoms and is released by your body’s mast cells as a response to stress. Prolonged or heightened levels of stress can worsen or possibly even lead to an allergic reaction.

This can cause skin symptoms, such as a rash or hives, or other allergy symptoms, such as runny nose and watery eyes. Stress can also trigger an asthma attack in people with asthma.

Obesity

Stress is believed to a play a major role in obesity. Studies have found that higher cortisol levels caused by chronic stress can influence several factors that contribute to weight gain, including poor sleep, which raises your cortisol levels further and leads to increases in belly fat. It also contributes to poor nutrition by increasing your cravings for sweets and refined carbohydrates.

High stress levels have also been shown to increase your chances of being unsuccessful at weight loss programs. Obesity is a risk factor in several diseases, including heart disease, diabetes, and cancer.

Heart disease

Research has found that all types of stress, including emotional stress, work stress, financial stress, and major life events, increase the risk of heart disease. Stress raises your blood pressure and cholesterol, which are directly linked to heart disease. Stress also significantly increases your risk of dying from a heart attack.

Pain

Stress can cause you to ache all over. Stress causes your muscles to tense, which can cause or worsen neck, shoulder, and back pain. Research shows that stress can also increase your sensitivity to pain. People with fibromyalgia, arthritis, and other conditions often report an increase in pain during times of stress.

Learning how to manage stress can help ease your symptoms and lower your risk of getting sick.

Some things that have been proven to help lower stress levels include:

If you’re having trouble managing stress, speak to your doctor about getting professional help. A counselor or therapist can help you identify the sources of your stress and teach you coping strategies that can help you to better deal with stress.