Variation in our body temperature isn’t always a bad thing. Body temperature is part of the body’s system called homeostasis that keeps things relatively normal and balanced inside and out, so the body can keep functioning normally.
Body temperature is cause for alarm when it becomes too high. Temperature for adults and children should be somewhere between 97.8 degrees Fahrenheit (or 36.5 degrees in Celsius) and 99 degrees Fahrenheit (or 37.2 degrees in Celsius.) 
Infants tend to be warmer, and their temperature is only cause for concern if it reaches higher than 100.4 degrees Fahrenheit (38 degrees in Celsius) for infants younger than 3 months, and 102.2 degrees Fahrenheit (39 degrees in Celsius) for infants 3 to 12 months of age.  Fever is cause for concern if it causes unmanageable discomfort, hallucinations, or if it’s accompanied by another alarming symptom. It’s important to take infants to a health care facility if the fever is also accompanied by vomiting, wheezing, skin discoloration anywhere in their body, or strange-colored diarrhea. Taking note of how the discharge looks, how much was expelled, and the last time that the infant ate will also help health care practitioners determine the exact cause of the fever.
Body temperature is also alarming if it’s too low. For adults and children, 95 degrees Fahrenheit (35 degrees celsius) is too cold. Infants should be kept above 97 degrees Fahrenheit (36.1 degrees Celsius.) Keep in mind that infants are more susceptible to dangerously low body temperature, also called hypothermia, and should be kept comfortably warm at all times. All that being said, there are other factors that could be altering your body temperature.
Surprising Facts About Body Temperature
1. Body Temperature Can Indicate All Kinds Of Things Besides Infection
It’s also a possible indication of a giant list of things, some of which you wouldn’t think might be associated – such as growing teeth, broken bones, poisoning, dehydration, and pain.
2. What you eat affects your temperature – but not quite how you would think
We regularly crave for ice cream and sweet, ice cold drinks when it’s hot. However, it’s not as simple as that: We require energy to digest these, making our bodies feel warmer later.  Vegetables and berries that are largely water are far more useful in cooling our body down. Spicy food actually has a more effective cooling effect because it makes us sweat, and sweating is one of our body’s cooling mechanisms when our temperature gets too high. In old times, strong alcoholic drinks such as brandy were given to people suffering from cold, however this causes a flush, giving the perception of warmth but in fact lowering the core temperature.
Anhidrosis is the uncommon condition of being unable to sweat. This can be caused by various factors like genetics, some skin disorders, medications, or nervous system damage.  Being unable to sweat can cause our body temperature to rise to dangerous levels without being able to cool down by sweating. This condition is especially dangerous for children, whose temperatures alter more rapidly than in adults.
4. Staying Warm During And After Surgery Decreases Infection
A study was conducted on the possible relation of body temperature regulation and surgical site infections. The study concluded that keeping patients warm, or at least at normal temperature during and right after surgery decreased the incidence of infection occurring at the site of the surgery. 
5. Women Are Warmer In Sleep Than Men
Our body temperature plays a role in our sleep in that when our body temperature drops, it’s usually an indication that it’s bed time. Hormones that are involved in a woman’s menstrual cycle make a woman’s body temperature higher than that of a man’s, especially when women are at a certain point in their cycle.  The study showed that women, on the other hand, get cooler sooner than men when it’s bed time. But our body’s temperature has no effect on how well we sleep.
 Fever. Medline Plus. http://www.nlm.nih.gov/medlineplus/ency/article/003090.htm
 How to Take your Baby’s Temperature. NHS Choices. http://www.nhs.uk/Conditions/pregnancy-and-baby/Pages/how-to-take-your-babys-temperature.aspx
 Surprising Foods that Toy with Your Body Temperature. Time Food and Drink. http://healthland.time.com/2013/06/15/surprising-foods-that-toy-with-body-temperature/
 Anhidrosis. Mayo Clinic. http://www.mayoclinic.org/diseases-conditions/anhidrosis/basics/risk-factors/con-20033498
 Thermoregulation and Risk of Surgical Site Infection. Infection Control and Hospital Epidemiology. http://www.jstor.org/stable/10.1086/660017
 Sleep and 24 hour body temperatures: a comparison in young men, naturally cycling women and women taking hormonal contraceptives. Journal of physiology. http://jp.physoc.org/content/530/3/565.full.pdf
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