Fever and Immune Function: The GAPS Explanation

Fever is part of the immune response, and Dr. Natasha Campbell-McBride gives it a prominent place in Gut and Physiology Syndrome. Her “Bless the fever!” section describes raised temperature as one of the body’s tools for responding to infection. Reading that explanation carefully means keeping ordinary cold symptoms, a baby’s fever and a seizure from becoming the same situation.^[1]

Our family has followed GAPS since July 2024. As a working, homeschooling mother of six, I want the explanation to lead to something useful at home. Understanding the terms helps me read the books carefully and keep food decisions connected to the protocol. You can read our family’s GAPS story for the experiences behind this blog.

Why GAPS Gives Fever an Immune Role

Campbell-McBride describes fever as a period of increased immune activity. She connects it with the destruction of microbes, removal of damaged material and reorganization of immune responses. Her broader interpretation also connects fever with chronic infections, cancer and autoimmunity. Those are the author’s claims in this chapter, not outcomes this article can promise after an individual fever.^[1]

The 2015 review cited in the book explains how fever-range temperatures influence both innate and adaptive immunity, including immune-cell movement. It gives a biological reason to consider temperature part of the immune response.^[2]

Fever, Sauna and Deliberate Heating

The chapter also mentions traditional heat practices: Russian banya, Scandinavian sauna, Turkish and Roman baths, sweat lodges and natural hot springs. Campbell-McBride places these alongside her discussion of fever, but they are different situations. An infection-related fever, a sauna session and medically supervised induced heating should not be treated as interchangeable home treatments.^[1]

Reading the Child and Baby Passages Carefully

The book describes the developing immune system of babies and young children and says that fever can be part of that development. It also explicitly distinguishes a common cold from a serious infection such as meningitis, which requires medical treatment. Its statement that many uncomplicated fevers last 12–24 hours is not a deadline for waiting when a child is seriously unwell.^[1]

If a baby three months old or younger has a rectal temperature of 100.4°F (38°C) or higher, call their pediatrician immediately. A seizure or suspected meningitis requires prompt medical help. For a seizure continuing beyond five minutes, call 911; do not wait for the longer interval printed in the book.^[3]

Rest, Fluids and Food as Appetite Returns

The everyday part of the chapter is about making room to rest: staying home, sleeping, drinking and returning to nourishing food as appetite comes back. Campbell-McBride names homemade meat stock, stock-based vegetable soup, the meat used to make the stock and cultured dairy when tolerated. She gives other meats on the bone as alternatives when chicken is not tolerated.^[1]

Keep homemade chicken meat stock available in portions you can warm without starting a whole cooking session. The food and immune-support guide explains the chapter’s food choices, including its active-infection guidance and the dairy-tolerance exception. A food plan is separate from deciding whether a fever needs assessment.

A baby’s feeding needs also differ from an adult’s. Keep breast milk or formula feeds going; do not use the book’s adult-style fasting or butter-and-honey mixture as a baby-feeding plan. Honey is not suitable for children younger than one year.^[4]

Febrile Seizures

Campbell-McBride distinguishes febrile seizures from epilepsy and includes a separate seizure passage. The current pediatric guidance linked below also explains that brief febrile seizures usually leave no lasting harm. If one occurs, protect the child from injury, put nothing in their mouth and contact their doctor. Fever-lowering medicines do not reliably prevent febrile seizures.^[3]

Do not give aspirin or willow preparations to a child to follow the book’s fever instructions. Aspirin during a viral illness is associated with Reye syndrome.^[5]

Making Rest Possible at Home

Before the next illness disrupts the week, decide what can be postponed, who can cover essential tasks and which accepted meals are easy to warm. Keep a thermometer and a written record of temperature, symptoms, fluids and any medicines given. A clear record is more useful than trying to remember everything after a sleepless night.

Keep Reading

Read the GAPS explanation of a common cold alongside GAPS immune-system guide. They explain how the fever discussion fits the wider protocol without making every illness the same.

For a more focused companion to the foundations material, look for the GAPS SOS course in my course catalog.

References

1. Campbell-McBride, N. Gut and Physiology Syndrome (2020), “Bless the fever!”, printed pages 63–66.
2. Evans SS, Repasky EA, Fisher DT. Fever and the thermal regulation of immunity: the immune system feels the heat. Nature Reviews Immunology. 2015;15:335–349. The book’s reference 42.
3. American Academy of Pediatrics. Febrile Seizures in Children; and Fever and Your Baby.
4. Centers for Disease Control and Prevention. Foods and Drinks to Avoid or Limit. Honey before 12 months; American Academy of Pediatrics, Treating Your Child’s Fever, fluids; and Fever symptom checker, breast milk and formula feeds.
5. American Academy of Pediatrics. Treating Your Child’s Fever. Aspirin and Reye syndrome.