Learn more for free: https://www.khanacademy.org/a/372h “Why Do We Get Fevers?” is part of our mission to provide free education to the modern world. You can help spread the knowledge by liking, commenting, and subscribing to the Science Saturdays channel. Science Saturdays is on Google+, Reddit, Blogger, and Twitter! Google+: http://tinyurl.com/nyj72dj Reddit: http://tinyurl.com/kb6438w Science Saturdays Blog: http://tinyurl.com/mzzxutv Twitter: http://tinyurl.com/p6mz58w Sources (To be updated for this video): http://tinyurl.com/qanj9uv If you would like to read along while you listen to the video, you can either turn on captions or read the script below. (CC are being added) If you can’t tell by my voice, I’ve been pretty sick this week. But I was determined to do a video nonetheless, and I figured it only be suitable to answer the question: Why do we get fevers? So, let’s dive into it. To start off, what is a fever? A fever can be simply be anything different than the average 98.6 degrees that the body is normally at, but since the body can fluctuate a degree or two during the day due to environmental factors, that isn’t a very accurate definition. A better way to characterize a fever is by oral temperatures higher than 100 degrees. But oral temperatures still aren’t incredibly accurate. The best way to measure a temperature is through the ear or the rectum, and a fever would then clock in at temperatures at or over 101 degrees. Fevers are most commonly caused by viruses, but can also be caused by toxins, a messed up hypothalamus, or a heat stroke. But as the number one cause of a fever is a virus, that’s what we’ll be focusing on today. When a virus infects your body, it often times travels through your bloodstream. But thankfully for us, our body has white blood cells. These guys travel around our body and when they find a harmful bacteria, they produce pyrogens that travel to our brain. These pyrogens then target the hypothalamus area of the brain which is the area that regulates body temperature. Our hypothalamus cranks up our body temperature and gives us the fever. But what’s the purpose of this all? Most bacteria that live in our body reproduce at the normal 98.6 degrees, so when our body temperature rises, the bacteria either stops reproducing or dies, making our body get better over time. So with this information in mind, a controversial topic is brought up. Should we take medication to lower fevers? The answer is no, unless it is a dire situation. By lowering body temperatures, we are allowing the infection to continue to grow and hurt us. And let’s not forget about those nasty side effects. Some side effects of ibuprofen, an active ingredient in most fever reducing medications, are… wait for it. Chest pains, weakness, upset stomach, diarrhea, rash, dizziness, headache, pain, numbness, bloody stools, shortness of breath, slurred speech, seizures, itching, and chills. So next time you’re taking a sick day off of work, put that medicine away and let your body do its work. Disclaimer: The statements made here have not been approved by the Food and Drug Administration. These statements are not intended to diagnose, treat or cure or prevent any disease.