# High or low body temperature **URL:** \ **Category:** Factual Questions\ **Created:** [February 16, 2017, 4:07pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984 "2017-02-16T16:07:18Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![Loach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/loach/32/350_2.png) [@Loach](https://boards.straightdope.com/u/Loach)\ **Post date:** [February 16, 2017, 4:07pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/1 "2017-02-16T16:07:18Z")
I have read that having a low body temperature can be a sign of infection or other health issues. Is it considered better, worse or neutral compared to an elevated temperature? Let’s say an adult who has always measured his temperature as 98.6 like clockwork his entire life is feeling crappy. His temperature is measured at 97.6 for 24 hours. His twin brother is also feeling crappy and has a temperature of 99.6. Can any conclusions be drawn? Are both equally sick? What is going to happen with the Yankees this year? ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [February 16, 2017, 4:19pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/2 "2017-02-16T16:19:01Z")
Well, I am neither a doctor nor do I play one on TV, but a fever is an immune response of your body attempting to fight off an infection by cooking it. It means that something is wrong, but your body is working on it. A slightly lower body temperature, though? It actually makes your body a more cozy home for infections, and off the top of my head, I don’t know of any positive biological reasons why your body would be lowering it’s temperature. I’ve skimmed over [this](http://drsircus.com/light-heat/low-body-temperature-symptoms-causes-treat/) pretty well and it doesn’t seem to be quack info. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [February 16, 2017, 4:22pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/3 "2017-02-16T16:22:07Z")
Reading more from the above link, here’s a good block 'o text: \*[Dr. David Jernigan](http://davidjernigan.blogspot.com.br/2010/01/chronic-fatigue-syndrome-and-low-body.html) says, “Much emphasis in conventional medicine is usually placed upon feverish conditions; however, a low body temperature can be a much more sinister condition. Where a fever can be viewed as an active developmental and corrective process of the healthy body, a low body temperature can never be viewed as a normal or healthy condition, nor is it a mechanism for a learning or developmental process in the body. The colder a body becomes, the slower the electrical oscillatory rate and therefore the thicker, more viscous, or syrupy the body fluids become. The more viscous the fluids become the more difficult it is for the body to push the fluids through the body. The lymph fluids that are normally supposed to bathe the outsides of all of your cells become progressively stagnant as it is too thick to move efficiently.” - \*“A low body temperature creates a happy home for viruses and chronic infections, and is a sign of degeneration and gradual cellular death. The problem with a low core temperature is that no effective immune response can be mounted therefore no fever is generated and infections go undetected. The sickest person is one who gets the same infections but never miss a day of work because there is no response by their immunes system, so they have a false sense of wellness as healthier individuals go through healthy fevers and immune responses that may cause them to miss work. Low body temperature is the plague of the 21st century. People with low body temperature have a weak reaction to even the most ideal medicines and therapies,” continues Jernigan. \* ---
**Author:** ![Lasciel](https://avatars.discourse-cdn.com/v4/letter/l/e79b87/32.png) [@Lasciel](https://boards.straightdope.com/u/Lasciel)\ **Post date:** [February 16, 2017, 4:22pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/4 "2017-02-16T16:22:16Z")
Low body temperature for me has always been a sign that my body has pretty much given up the fight. It’s one of my best markers for when I need to go to the doctor for antibiotics, especially for something in the “irritating but not actively deathly” category like (for me) a uti or skin-staph infection. When I’m tired and achey and my fever is a few degrees low? Gotta suck it up and actually go get things sorted out. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [February 16, 2017, 4:23pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/5 "2017-02-16T16:23:04Z")
My experience is that a high temperature will yield instant interest and concern, and a lower than usual temperature little more than “thats interesting.” High temperatures can be life threatening in short order. Low body temperature might be symptomatic of a few things, but little of much import unless there are other symptoms, in which case it is more about differential diagnosis than actually worrying about that particular symptom. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [February 16, 2017, 4:27pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/6 "2017-02-16T16:27:22Z")
> [@Darren\_Garrison](#): > > Dr. David Jernigan says,…The colder a body becomes, the slower the electrical oscillatory rate and therefore the thicker, more viscous, or syrupy the body fluids become. The more viscous the fluids become the more difficult it is for the body to push the fluids through the body. The lymph fluids that are normally supposed to bathe the outsides of all of your cells become progressively stagnant as it is too thick to move efficiently… Say what? That is up there with chakras, homeopathy and essential bodily fluids. :eek: ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [February 16, 2017, 4:36pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/7 "2017-02-16T16:36:35Z")
> [@Francis\_Vaughan](#): > > Say what? That is up there with chakras, homeopathy and essential bodily fluids. :eek: Yeah, I hadn’t read it too closely before I excerpted it… ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [February 16, 2017, 5:14pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/8 "2017-02-16T17:14:40Z")
> [@Francis\_Vaughan](#): > > Say what? That is up there with chakras, homeopathy and essential bodily fluids. :eek: Yeah, that definitely sounds like quack info. “Low” is often relative to what is normal for the individual. 98.6 is just a statistical average with some averaging higher and some lower and it varies within individuals over the time of day (by 2 degree F commonly, lowest about two hours before due to wake up), and for women, with point in the menstrual cycle. Mood can even impact it and variably depending on the person. Serious overwhelming infections (sepsis) can cause low body temperature. That’s a person seriously sick and there will be other clues to that than low temperature alone. Given a septic individual a low temperature is even more scary than a high one with more of chance of not pulling through. Also some older folks and those with immunosuppressed conditions won’t run fevers when ill. Some people with hypothyroidism will run low too. A degree or two either way between twin both feeling crappy would not be enough to draw any conclusion from. ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [February 16, 2017, 6:42pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/9 "2017-02-16T18:42:54Z")
Remember that 98.6 is a spurious representation of accuracy, based on the conversion of the C scale to F. Normal is not defined down to the tenth of a degree. The human body temperature was defined as 37-C, rounded off to the nearest degree Celsius. Which means the actual value was found to be somewhere between 36.5 and 37.5 Celsius – in other words, between 97.7-F and 99.5-F. Any value in that range is, if converted to Celsius and rounded to the nearest degree, is 37, the definition of normal. So, 99.5 and 97.7 would both register as a clinically normal 37-C when rounded, and in both cases, a metric-thinking doctor would say 37, normal. ---
**Author:** ![Surreal](https://avatars.discourse-cdn.com/v4/letter/s/eada6e/32.png) [@Surreal](https://boards.straightdope.com/u/Surreal)\ **Post date:** [February 16, 2017, 7:24pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/10 "2017-02-16T19:24:57Z")
> **[Long-term calorie restriction, but not endurance exercise, lowers core body...](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117452/)** > > Reduction of body temperature has been proposed to contribute to the increased lifespan in calorie restricted animals and mice overexpressing the uncoupling protein-2 in hypocretin neurons. However, nothing is known regarding the long-term effects of... > [@](#): > > In the Baltimore Longitudinal Study of Aging (BLSA) men with a core body temperature below the median lived significantly longer than men with body temperature above the median in the absence of Caloric Restriction. ---
**Author:** ![Omar\_Little](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/omar_little/32/269_2.png) [@Omar\_Little](https://boards.straightdope.com/u/Omar_Little)\ **Post date:** [February 16, 2017, 10:23pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/11 "2017-02-16T22:23:40Z")
> [@Loach](#): > > What is going to happen with the Yankees this year? > **[New York Yankees 2017 preview](https://www.foxsports.com/stories/mlb/new-york-yankees-2017-preview)** > > Here come the Baby Bombers World series odds: 20-1 ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [February 18, 2017, 2:50am UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/12 "2017-02-18T02:50:47Z")
> [@Surreal](#): > > [Long-term calorie restriction, but not endurance exercise, lowers core body temperature in humans - PMC](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117452/) I _suspect_ that that is true but that’s a line referencing [an article](http://science.sciencemag.org/content/297/5582/811) which itself only references a 1984 study while explicitly stating that they do not know what the caloric intake was in the lower half. The closest I can find to something assessable of that data related to it is this on [BMR](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4984846/) which might guess correlates with temperature some. Interesting speculation there that higher BMR might be a sign of uncontrolled inflammation. > [@](#): > > The relationship between BMR and mortality was curvilinear with minimum mortality between 31.0 and 33.0 kcal/m2/h and with progressively rising mortality above 33.0 kcal/m2/h. These findings are the first evidence based on longitudinal data showing that a blunted capacity to reduce BMR with age is a significant risk factor for mortality in the general population. > > We confirmed that BMR declines with age (25,26,36,37) and showed that the rate of decline accelerates at older ages (38). Interestingly, the age-related decline of BMR was blunted in participants who died compared to those who were still alive at the end of the follow-up period. These results are compatible with the notion that long-lived individuals are able to preserve a low energy metabolism, perhaps reflecting good health status. … > > … A potential clinical application of this concept stems from the hypothesis that an excessively high BMR, such as one caused by uncontrolled inflammation, is an early index of the perturbation of health status … ---
**Author:** ![P-man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/p-man/32/3606_2.png) [@P-man](https://boards.straightdope.com/u/P-man)\ **Post date:** [February 18, 2017, 4:13am UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/13 "2017-02-18T04:13:00Z")
Is a 99.4 temp worse for someone who normally runs 97 or so than it is for someone who is usually at 98.6? Normally I run below 98; is 100 really bad for me? ---
**Author:** ![Chimera](https://avatars.discourse-cdn.com/v4/letter/c/8e8cbc/32.png) [@Chimera](https://boards.straightdope.com/u/Chimera)\ **Post date:** [February 18, 2017, 4:44am UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/14 "2017-02-18T04:44:22Z")
> [@P-man](#): > > Is a 99.4 temp worse for someone who normally runs 97 or so than it is for someone who is usually at 98.6? Normally I run below 98; is 100 really bad for me? I’ve always run around 97.6, so if I’m at 99-100, I’m usually sick, but don’t consider that a real ‘fever’. ---
**Author:** ![SeaDragonTattoo](https://avatars.discourse-cdn.com/v4/letter/s/df705f/32.png) [@SeaDragonTattoo](https://boards.straightdope.com/u/SeaDragonTattoo)\ **Post date:** [February 18, 2017, 4:52am UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/15 "2017-02-18T04:52:28Z")
> [@Chimera](#): > > I’ve always run around 97.6, so if I’m at 99-100, I’m usually sick, but don’t consider that a real ‘fever’. I agree with this, I also tend to run under 98. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [February 18, 2017, 4:09pm UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/16 "2017-02-18T16:09:38Z")
> [@P-man](#): > > Is a 99.4 temp worse for someone who normally runs 97 or so than it is for someone who is usually at 98.6? Normally I run below 98; is 100 really bad for me? No. Whether or not it should be considered “a fever” is a matter of definition. Is “fever” 38 C for all or an individual’s average normal plus 1 C? But a mild to moderate “fever” is not per se “bad”. It is a likely sign of fighting something off and part of how a body does that. I wouldn’t say that it is “cooking” germs but the cycling through different temperature ranges is, in the context of dealing with infection, a good thing. (I’d be happy to share my speculations as to why if anyone wants to hear it.) The reason to treat is for comfort’s sake. The issue of course is what the body is fighting off and the significance of the fever, and its magnitude, in that assessment. Is it day one of an illness in January and you have cough runny nose sore throat and muscle aches? You likely have influenza, no test needed. Have you been snotty and coughing for five days and now suddenly are spiking up? More likely a bacterial infection, maybe pneumonia. A toddler day spiking up high with the onset of a snotty nose a bit crabby with the spikes but more or less fine as it drops back down? Virus of the week club. Still spiking that high four to five days into it with nose getting worse, more crabby and not sleeping? Possibly gone into an ear infection. Context matters. Doubling back to the article on BMR with aging, BMR reasonably assumed to correlate with body temperature, is [this](https://www.ncbi.nlm.nih.gov/pubmed/16398904) bit of support: > [@](#): > > **Older is colder: temperature range and variation in older people** … The average age of subjects was 80.7. Temperatures ranged from 94.0 degrees F to 99.6 degrees F. … Older subjects have mean oral body temperatures lower than 98.6 degrees F. Relatively few even achieve this temperature. In nursing home residents, the oldest were coldest and failed to demonstrate a diurnal rise in body temperature. … ---
**Author:** ![BuckChongo](https://avatars.discourse-cdn.com/v4/letter/b/ee7513/32.png) [@BuckChongo](https://boards.straightdope.com/u/BuckChongo)\ **Post date:** [February 19, 2017, 2:13am UTC](https://boards.straightdope.com/t/high-or-low-body-temperature/779984/17 "2017-02-19T02:13:57Z")
I had TBI and my body doesn’t regulate temp efficiently. If I’m in a 75 degree room in shirt sleeves I have to watch out or my temp will start heading south of 97 until I get violent chills almost like a seizure. Then as I warm up under blankets in sweat suit if I doze off I’ll wake up sweating like an over baked sweet potato. Extreme environmental conditions are much easier to deal with than room temperature (I’m the guy you see wrapped up in a red and white rebozo at the office). 96 and 104 are about equally unpleasant.