Though body aches are never enjoyable, they are evidence that your body’s immune system is working.

When a virus enters your body, your immune system gets ready for battle.

As the white blood cells fight the infection, you suffer the side effects: headaches, fever, runny nose, and sore throat. Along with these symptoms, you may experience muscle weakness (myositis) and joint and muscle pain (myalgia). These side effects may be your immune system’s way of making you rest.

Your immune system, not the virus, causes muscle aches and joint pain.

During the immune response, white blood cells produce glycoproteins called interleukins. These interleukins cause the symptoms associated with colds, flu, and other bacterial or viral infections.

Richard Deem, a senior researcher, and specialist at Cedars-Sinai Medical Center in Los Angeles provided a concise explanation of the body’s immune response. In his 2001 post on the message board, Deem summarized the process.

According to his post, a fierce battle rages inside the body it contracts the flu virus. The immune system sends antibodies to find and bind the influenza receptors. This defensive action blocks the virus and prevents the infection from spreading to other healthy cells.

After the immune system traps the infection, it launches the next phase of the attack. The body sends T cells and white blood cells to destroy mucosal cells affected by the virus. During the assault, the white blood cells produce cytokines and interleukins. These chemicals kill abnormal cells and recruit immune cells to the infected area. This microscopic battle for wellness is intense and produces the typical flu symptoms.

In 90 percent of the influenza cases, the Interleukin-6 (IL-6) and its associated cytokines cause muscle and joint pain. Other interleukins may produce different symptoms.

You can share this information with others through a YouTube video entitled Why The Flu Causes Aches & Pain. The video presents this 50-thousand-foot view of body’s immune response in an entertaining way.

Treat your body right during the flu.

If you contract the flu, stay home, rest, and drink plenty of fluids. Give your white blood cells the resources they need to win the chemical warfare raging inside your body.

Most people feel better in 3 to 5 days, though some may feel weak and tired for up to a week.

If body aches and joint pain continue for more than a week after other flu symptoms have disappeared, make an appointment with your primary care provider or an orthopedic specialist. Your aches and pains may have another cause.