Immune Function: A Practical Checklist
Immune Function: what is worth doing, what is worth avoiding, and when to stop and see a doctor.
The network of cells and proteins that identifies and removes pathogens and damaged cells. 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: 7-9 hours
- Restricted sleep: associated with reduced antibody response to vaccination
- Most useful single change: Take the vaccines you are eligible for, including annual flu.
- Commonest mistake: Products marketed as immune boosters.
- See a doctor if any of the signs under "When to speak to a doctor" below apply to you.
Do
- Take the vaccines you are eligible for, including annual flu
- Protect sleep, which has the clearest link to infection risk
- Take vitamin D through autumn and winter
- 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 numbers behind the list
Every item above comes from these figures, published in the guidance listed at the foot of the page.
| Measure | Figure |
|---|---|
| Adult sleep recommendation | 7-9 hours |
| Restricted sleep | associated with reduced antibody response to vaccination |
| Most effective specific intervention | vaccination where eligible |
| Supplements | help people who are deficient, not people who are not |
| Evidence for high-dose vitamin C | at best a small reduction in cold duration |
If you change one thing
Take the vaccines you are eligible for, including annual flu. Start there. The rest of the list keeps.
Where to go next
- Popular Beliefs About Immune Function, and What Is Actually Published
- Immune Function: A Beginner-Friendly Start
- Immune Function — the reference entry
- Vaccination: What the Evidence Actually Says
- Colds and Flu: What Published Guidance Supports
When to speak to a doctor
See a GP 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 take advice from their own clinical team.
Where this comes from
- NHS — How to boost your immune system
- British Nutrition Foundation — nutrition and immunity
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, summarised or generalised 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 a GP, 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 999.
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