Are Fevers 'Paleo'?

Most definitely yes. Don't let your physician tell you otherwise.

Fever is one of the body's self-defense mechanisms. Since many pathogens can only exist in narrow temperature ranges, the body attempts to raise its temperature above that range, and bake them out. As Wikipedia explains:

Usefulness

There are arguments for and against the usefulness of fever, and the issue is controversial. There are studies using warm-blooded vertebrates and humans in vivo, with some suggesting that they recover more rapidly from infections or critical illness due to fever. A Finnish study suggested reduced mortality in bacterial infections when fever was present.

In theory, fever can aid in host defense. There are certainly some important immunological reactions that are sped up by temperature, and some pathogens with strict temperature preferences could be hindered. Fever in children is believed to train the immune system and prevent asthma. White blood cells also rapidly proliferate due to the suitable environment and can also help fight off the harmful pathogens and microbes that invaded the body.

Research has demonstrated that fever assists the healing process in several important ways:

• Increased mobility of leukocytes.

• Enhanced leukocytes phagocytosis.

• Endotoxin effects decreased.

• Increased proliferation of T cells.

As we learned with barefoot running, the body doesn't evolve mechanisms for no reason. Evolution is efficient. And just as hindering your Achilles' tendon's proper function with a block of foam under your heel is unlikely to improve your running performance, so too is it unlikely that interfering with your body's immune system is likely to improve its function.

"Many parents experience fear and anxiety when their child comes down with a fever, unaware that fever is an ancient, often beneficial, response to infection. The fever response is conserved across all mammals and many vertebrate classes. (Even reptiles and other cold-blooded animals fare better against infection when they develop fever by soaking up the sun's heat. [See P.P.S. below]) Among other potential adaptive benefits, a higher temperature can inhibit the growth of bacterial strains that lack sophisticated mechanisms for coping with heat shock...." (Gross, 2006)

(That paper is fascinating: you can apparently induce a fever in a mouse by introducing "bacterial endotoxins", AKA, lipopolysaccharides (LPS). In other words, upon detecting the signs of bacteria, the body starts heating up.)

However, fevers are unpleasant, and some of the effects of fever, like febrile seizures, can be alarming. For the most part, however, my philosophy is to let them run. I've been through some pretty unpleasant illnesses that gave me high, multi-day fevers, and I just let 'em rip. Often I'll wear a hat just to help my body bake the little pathogens out. Happily, since adopting a paleo diet, this is necessary much less often.

The medical profession, despite knowing intellectually that fevers are almost always harmless if not beneficial, tosses out immune-suppression pills at the drop of a hat. Crocetti et al. in 2001 noted:

"Fever Phobia Revisited: Have Parental Misconceptions About Fever Changed in 20 Years?

"Fever is one of the most common reasons that parents seek medical attention for their children. Parental concerns arise in part because of the belief that fever is a disease rather than a symptom or sign of illness. Twenty years ago, Barton Schmitt, MD, found that parents had numerous misconceptions about fever. These unrealistic concerns were termed “fever phobia.”...

"...Forty-six percent of caregivers listed doctors as their primary resource for information about fever. Caregivers who stated that they were very worried about fever were more likely in the past to have had a child who was evaluated for a fever, to have had blood work performed on their child during a febrile illness, and to have perceived their doctors to be very worried about fever...."

So people are scared of fevers because their doctors are scaring them. That's logical, at least, even if it's incorrect. Amusingly, the doctors are the ones blaming the patients they've scared for being scared. The paper winds up with:

"...Fever phobia persists. Pediatric health care providers have a unique opportunity to make an impact on parental understanding of fever and its role in illness...."

That's a polite way of saying: Pediatricians, stop scaring your patients' parents about fevers. Convey correct information.

And yet even fever-friendly pediatricians dose kids with anti-pyrectics... Despite studies like this:

“The Effect of Antipyretic Therapy Upon Outcomes in Critically Ill Patients: A Randomized, Prospective Study

“Background: Despite the large body of evidence suggesting a beneficial role of fever in the host response, antipyretic therapy is commonly employed for febrile critically ill patients. Our objective was to evaluate the impact of antipyretic therapy strategies on the outcomes of critically ill patients.

“Methods: Patients admitted to the Trauma Intensive Care Unit over a nine-month period were eligible for inclusion, except those with traumatic brain injury. Patients were randomized on day three of the ICU stay into aggressive or permissive groups. The aggressive group received acetaminophen 650 mg every 6 h for temperature of >38.5 degrees C and a cooling blanket was added for temperature of >39.5 degrees C. The permissive group received no treatment for temperature of >38.5 degrees C, but instead had treatment initiated at temperature of >40 degrees C, at which time acetaminophen and cooling blankets were used until temperature was <40 degrees C. Patient demographics, daily temperatures, systemic inflammatory response syndrome (SIRS) scores, multiple organ dysfunction syndrome (MODS) scores, and infections and complications were recorded.

“Results: Between December, 2002 and September, 2003, 572 patients were screened, of whom 82 met criteria for enrollment. Forty-four patients were randomized to the aggressive group and 38 patients were randomized to the permissive group for a total of 961 and 751 ICU days, respectively. There were 131 infections in the aggressive group and 85 infections in the permissive group (4 +/- 6 vs. 3 +/- 2 infections per patient, p = 0.26). There were seven deaths in the aggressive group and only one death in the permissive group (p = 0.06, Fisher Exact Test). The study was stopped after the first interim analysis due to the mortality difference, related to the issues of waiver of consent and the mandate for minimal risk.

“Conclusions: Aggressively treating fever in critically ill patients may lead to a higher mortality rate.” (Schulman, 2005)

I think it's safe to say that if you expire due to an infection succeeding because your doctor has disabled part of your immune response, you've suffered from a Disease of Civilization.

(Also from that Wikipedia link above:

"Hyperpyrexia is a fever with an extreme elevation of body temperature greater than or equal to 41.5 °C (106.7 °F).[14] Such a high temperature is considered a medical emergency as it may indicate a serious underlying condition or lead to significant side effects."

If you were wondering when you should start worrying about a fever...)

P.S. After reading this, my ex-wife wrote:

"So the test was stopped because of the mortality rate, yet hospitals & Dr.s continue to practice the aggressive treatment?"

Yeah, pretty much. Here's an article on treating fever (Davis, 2022), and the notion of letting the fever run its course to let the body heal itself isn't even mentioned as an option, nor is the fact that the fever is part of the body's defense protocol. The author:

"...is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the [sic] MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications."

Sadly, medical professionals prescribing courses of action that have no support in, or are contradicted by, the scientific literature is par for the course.

P.P.S. This is a cool link, expanding how even cold-blooded animals that can't control their body temperature well benefit from fever:

He doesn’t look feverish…

"...In a dramatic demonstration of fever's benefits, researcher Matthew Kluger infected desert iguanas with bacteria.

"Because these lizards are cold-blooded, they could only warm their bodies by seeking outside heat — in this case, sunlamps. All except one of 13 iguanas sought the warmth to raise their temperatures, and those 12 survived; the other one died.

After that, Kluger injected 12 other iguanas with live bacteria, and also gave them a fever-fighting drug. Five of them failed to develop a fever, and died as a result. The other seven, which somehow became feverish despite the drug, survived.

Despite experiments like this, scientists haven't yet answered all their questions about this common and ancient body symptom." (PBS, 2001)

So if your doctor suggests you take medicine to lower your fever, you should ask him whether he wants you to get well or not.

P.S. A follow-up of sorts:

Fevers and Cancer.

P.P.S. 2020:

“Conclusion: In animal models, treatment with antipyretics for influenza infection increases the risk of mortality. There are no randomized placebo-controlled trials of antipyretic use in influenza infection in humans that reported data on mortality and a paucity of clinical data by which to assess their efficacy.” (Eyers, 2010)

"The effect on mortality of antipyretics in the treatment of influenza infection: systematic review and meta-analyis"

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References

Crocetti, M., Moghbeli, N., & Serwint, J. (2001). Fever Phobia Revisited: Have Parental Misconceptions About Fever Changed in 20 Years? Pediatrics, 107(6), 1241–1246. https://doi.org/10.1542/peds.107.6.1241

Davis, C. P. (2022, August 20). Fever in Adults: High & Low Grade Fever and How to Reduce a Fever [Informational]. eMedicineHealth. https://www.emedicinehealth.com/fever_in_adults/article_em.htm

Eyers, S., Weatherall, M., Shirtcliffe, P., Perrin, K., & Beasley, R. (2010). The Effect on Mortality of Antipyretics in the Treatment of Influenza Infection: Systematic Review and Meta-Analyis. Journal of the Royal Society of Medicine, 103(10), 403–411. https://doi.org/10.1258/jrsm.2010.090441

Gross, L. (2006). Anatomy of a Fever. PLOS Biology, 4(9), e305. https://doi.org/10.1371/journal.pbio.0040305

Function of Fever. (2001). [Informational]. PBS Evolution Library. https://www.pbs.org/wgbh/evolution/library/10/4/l_104_04.html

Schulman, C. I., Namias, N., Doherty, J., Manning, R. J., Li, P., Elhaddad, A., Lasko, D., Amortegui, J., Dy, C. J., Dlugasch, L., Baracco, G., & Cohn, S. M. (2005). The Effect of Antipyretic Therapy Upon Outcomes in Critically Ill Patients: A Randomized, Prospective Study. Surgical Infections, 6(4), 369–375. https://doi.org/10.1089/sur.2005.6.369