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Immune Function: What To Do

The network of cells and proteins that identifies and removes pathogens and damaged cells.

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Oranges — Immunity
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It is a balance rather than a dial: too much activity causes allergy and autoimmune disease, which is why "boosting" is the wrong goal.

Key takeaways

  • Adult sleep recommendation: 7 or more hours a night
  • Restricted sleep: linked to a weaker antibody response to vaccination
  • Most useful single change: Get the vaccines recommended for you, including a yearly flu shot.
  • Commonest mistake: Products marketed as immune boosters.
  • See a doctor if any of the signs under "When to get help" below apply to you.

Do

  • Get the vaccines recommended for you, including a yearly flu shot
  • Protect sleep, which has the clearest link to infection risk
  • Meet the vitamin D RDA of 15 mcg (600 IU) for most adults from food, fortified products or a supplement
  • Wash your hands; the unglamorous measures still work

Do not

  • Products marketed as immune boosters
  • High-dose supplements on the assumption more is better
  • Treating supplements as a substitute for vaccination

The figures behind the list

Each item above follows from these, published in the guidance named at the foot of the page.

Published figures for Immune Function
MeasureFigure
Adult sleep recommendation7 or more hours a night
Restricted sleeplinked to a weaker antibody response to vaccination
Most effective specific measurevaccination where recommended
Supplementshelp people who are deficient, not people who are not
Evidence for high-dose vitamin Cat best a small reduction in how long a cold lasts

Where to go next

When to get help

See your doctor for frequent, severe or unusually persistent infections, infections needing repeated antibiotics, or unexplained weight loss, night sweats or persistent swollen glands. People taking immunosuppressants or having chemotherapy should follow advice from their own care team. Call 911 for difficulty breathing, confusion, or a high fever with a stiff neck or a rash that does not fade under pressure.

Where this comes from

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.

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