Immune Function: Common Questions Answered

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

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.

What is Immune Function?

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

Why does it matter?

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

Adult sleep recommendation for Immune Function?

7-9 hours.

Restricted sleep for Immune Function?

Associated with reduced antibody response to vaccination.

Most effective specific intervention for Immune Function?

Vaccination where eligible.

Evidence for high-dose vitamin C for Immune Function?

At best a small reduction in cold duration.

What is the single most useful thing to do?

Take the vaccines you are eligible for, including annual flu.

What is the most common mistake?

Products marketed as immune boosters.

When should I see 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 to go next

• Immune Function: A Practical Checklist
• Popular Beliefs About Immune Function, and What Is Actually Published
• 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.