Intermittent Fasting Tip: Fasting When You’re Sick

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Intermittent Fasting Tip: Fasting When You’re Sick

Common cold and flu-like symptoms can be caused by either viruses or bacteria

Cold and flu infections are initially caused by viruses, specifically the rhinovirus and influenza virus

However, being infected with these viruses lowers your defense against bacteria, raising your chances of simultaneously developing a bacterial infection, whose symptoms are often similar to your initial ones

abstaining from eating limits the supply of nutrients, such as iron and zinc, that the infecting agent needs to grow and spread

For example, with fever, iron sequestration participates in the inhibition and killing of bacterial pathogens

During the APR, plasma levels of iron are reduced – Iron is a critical micronutrient involving numerous cell functions in prokaryotes and eukaryotes, and is especially important in proliferating cells

Although adequate iron is needed for a properly functioning immune system, the host must strike a balance between providing for its own needs and defenses while minimizing access to iron by pathogens

The importance of iron for bacteria and fungi is highlighted by their production of iron- trapping siderophores that increase the ability of pathogens to compete for this critical micronutrient.

*In short, fasting may be best to promote healing from bacterial infections, while eating food may be a better way to fight viral infections*

When animals are infected they stop eating and they switch to a fasting metabolic mode

*Fever is intracellular and food increases IFN-y (fever); cold is extracellular and fasting increases IL-4*

The adaptive immune response uses different strategies to ward off infection by pathogens – a subset of T lymphocytes, the CD4-expressing T helper (Th) cells, are important in directing this strategy

So-called Th1 cells primarily stimulate the cell-mediated immune response against intracellular invaders by activating macrophages and CD8+ cytotoxic T lymphocytes

Th2 cells favor the B-cell-dependent humoral immune response against extracellular organisms

Whereas gamma interferon (IFN-γ) is the hallmark Th1 cytokine, interleukin-4 (IL-4) is an important Th2 cytokine

Which is why, in cases of mild or moderate illness, it’s likely worth a try – so the saying, “Feed a Cold, Starve a Fever” might have some merit

Fasting may be best to promote healing from bacterial infections, while eating food may be a better way to fight viral infections

Colds are viral and fevers are bacterial

With a fever, the benefits are:

Promoting apoptosis of infected or neoplastic cells; eliciting pathogen heat shock proteins (HSPs) to enhance immune responses; invoking host HSPs that protect against pathogen damage; enhancement of inflammatory/immune cell function; and downregulation of immune responses by promoting apoptosis of lymphocytes and neutrophils

Increased amounts of glucose are used by infected cells; and tumor cells and other proliferating cells shift to aerobic glycolysis

Thus, proliferating pathogens are susceptible to increased nutrient needs and to the vulnerability of replication and synthesis

Bacteria feed off food

Viruses aren’t alive so no point in starving them; help the rest of your cells instead


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