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The Surprising Reason You Feel Awful When You're Sick

man sick with the flu

Man sick with the flu (DmitryMo, iStockphoto)

Viruses can make you feel awful! This article explains how feeling bad might be your immune system’s way of helping you heal.

The surprising reason you feel awful when you’re sick (2016) by Marco A. Sotomayor, TED Ed (5:00 min.).

Have you ever had the flu? It feels horrible, doesn’t it? Your nose runs. Your head aches. You feel hot all the time. Your appetite disappears. And you probably want to stay in bed.

But why does being sick feel so bad? Well, some scientists think that unpleasant symptoms like fever, fatigue, and a lack of hunger and thirst actually help you get better! They think these symptoms are your immune system’s way of preventing the pathogen from spreading to your blood and organs. A pathogen is what gives you an infection or makes you sick. This includes bacteria and viruses.

Here are some examples. When your body temperature goes up, it slows down the spread of the pathogen. The more you sleep, the more energy your body has left over to fight the infection. When you stop eating, your liver can take up the iron in your blood. Bacteria need iron to live, too. So if your infection is caused by bacteria, your liver taking up the iron can starve them.

When you’re sick, you might find that you’re less thirsty than usual. That’s a good thing! It means you’ll cough less, sneeze less, and have a lower risk of infecting people around you. But even if you do not feel thirsty, you should still drink lots of fluids. This will keep you from getting dehydrated.

When you’re sick, you might also feel grumpy or sad. That’s because the macrophages fighting the infection in your body send out cytokines. These cytokines can affect the parts of your brain that deal with emotions and reasoning.

So the next time you feel awful when you’re sick, remember that this is your body’s way of protecting you from getting worse. So rest up, drink lots of fluids, and get well soon!

  • Have you ever had the flu? How do you feel when you “have the flu?”
  • Do you “catch” every illness that comes around or are you able to avoid most illnesses?
  • Many pathogens, like viruses, can be passed from one person to another. What are some steps that are used by you, your family, schools, businesses, public buildings, etc. to prevent the illness through the transfer of pathogens?
  • Some people spread illness because they go to school or work even when they are sick. Should people be prevented from going to school or work if they have the flu? Why/why not?
  • What are some of the typical symptoms of the flu? Why do they occur?
  • Other than the flu virus, what other types of viruses/pathogens are you aware of?
  • How does the immune system first respond once it detects a pathogen in the bloodstream? 
  • How does the immune system interact with the nervous system when your body is fighting the flu?
  • What is an autoimmune disease? 
  • How has the study of the brain and psychology expanded our understanding of the symptoms of illness and disease? Medical science has developed many medicines and surgical procedures that are allowing people to recover from illnesses and live longer lives. In the past, these same illnesses often resulted in death. What are the pros and cons of more people living a long life?
  • This video and article can be used to support teaching and learning of Health, Biology and Anatomy related to pathogens, the immune system, viruses, bacteria and the nervous system. Concepts introduced include immune system, pathogen, dehydration, macrophages and cytokines. 
  • While this video goes into greater depth than needed at the junior science level, teachers can use this video when discussing the interconnectedness of body systems. Given the general interest level related to illness, this could make an excellent enrichment lesson. At the senior biology level, this video provides an excellent introduction of the immune response. Teachers may wish to explore students’ current understanding of illness before beginning the lesson using the learning strategy Admit Slip. Ready-to-use reproducibles are available for this topic in [Google doc] and [PDF].
  • To help consolidate learning after viewing the video and reading the article, teachers could have students create a graphic organizer or an infographic summarizing the symptoms of illness and what to do to help the immune system fight an illness. See the Infographic Creator learning strategy. 
  • To go further into the details of the immune response with senior biology students, teachers could also have students compare information conveyed in the video The Surprising Reason You Feel Awful When You’re Sick with information presented in the article The Immune Response using a Print-Video Venn Diagram learning strategy. Ready-to-use reproducibles using the learning strategy Print-Video Venn Diagram for this article are available in [Google doc] and [PDF] formats.
  • Discussion of the flu can naturally lead to talk of vaccines as methods of controlling diseases caused by viruses. The following Let’s Talk Science resources will provide excellent extension opportunities:

Connecting and Relating

  • Have you ever had the flu? How do you feel when you “have the flu?”
  • Do you “catch” every illness that comes around or are you able to avoid most illnesses?

Relating Science and Technology to Society and the Environment

  • Many pathogens, like viruses, can be passed from one person to another. What are some steps that are used by you, your family, schools, businesses, public buildings, etc. to prevent the illness through the transfer of pathogens?
  • Some people spread illness because they go to school or work even when they are sick. Should people be prevented from going to school or work if they have the flu? Why/why not?

Exploring Concepts

  • What are some of the typical symptoms of the flu? Why do they occur?
  • Other than the flu virus, what other types of viruses/pathogens are you aware of?
  • How does the immune system first respond once it detects a pathogen in the bloodstream? 
  • How does the immune system interact with the nervous system when your body is fighting the flu?
  • What is an autoimmune disease? 

Nature of Science/Nature of Technology

  • How has the study of the brain and psychology expanded our understanding of the symptoms of illness and disease? Medical science has developed many medicines and surgical procedures that are allowing people to recover from illnesses and live longer lives. In the past, these same illnesses often resulted in death. What are the pros and cons of more people living a long life?

Teaching Suggestions

  • This video and article can be used to support teaching and learning of Health, Biology and Anatomy related to pathogens, the immune system, viruses, bacteria and the nervous system. Concepts introduced include immune system, pathogen, dehydration, macrophages and cytokines. 
  • While this video goes into greater depth than needed at the junior science level, teachers can use this video when discussing the interconnectedness of body systems. Given the general interest level related to illness, this could make an excellent enrichment lesson. At the senior biology level, this video provides an excellent introduction of the immune response. Teachers may wish to explore students’ current understanding of illness before beginning the lesson using the learning strategy Admit Slip. Ready-to-use reproducibles are available for this topic in [Google doc] and [PDF].
  • To help consolidate learning after viewing the video and reading the article, teachers could have students create a graphic organizer or an infographic summarizing the symptoms of illness and what to do to help the immune system fight an illness. See the Infographic Creator learning strategy. 
  • To go further into the details of the immune response with senior biology students, teachers could also have students compare information conveyed in the video The Surprising Reason You Feel Awful When You’re Sick with information presented in the article The Immune Response using a Print-Video Venn Diagram learning strategy. Ready-to-use reproducibles using the learning strategy Print-Video Venn Diagram for this article are available in [Google doc] and [PDF] formats.
  • Discussion of the flu can naturally lead to talk of vaccines as methods of controlling diseases caused by viruses. The following Let’s Talk Science resources will provide excellent extension opportunities:

How long the flu virus lasts in your body (2017)

infographic by Mandy Freeman depicting the timeline of the flu, includes some other facts about the history of influenza

What is the difference between a cold and flu? (2019) 

Information from the Centers for Disease Control and Prevention on how to tell the difference between having the flu or having a common cold.

How to boost your immune system (2018)

An article from Harvard Health Publishing—It turns out to be more complicated than you’d think!

Immune system: Diseases, Disorders and how it Functions (2018)

Article from Live Science gives an overview about immune system diseases and disorders, including a section on milestones in the history of immunology.

References

BBC Science. (2013, April 19). How does the body fight off a virus?

Mayo Clinic. (2019, April 11). Influenza (flu).