It’s that time of year again. Tissues in pockets, coughs echoing round the office, and a chorus of sniffles on the commute. While colds might feel inevitable this time of year, there’s plenty you can do to keep your immune system fighting fit, especially given that around 70% of your immune system lives in your gut, meaning that tapping into your gut:immune connection could offer some relief.
In this blog, we’ll equip you with practical, evidence-based tips to support your immune system and keep colds and flu at bay this winter.
Prevention: what to do to help prevent colds and flu
When it comes to winter bugs, the best defence is a good offence. Here’s what to do to support your immune system and lower your chances of picking up seasonal bugs.
1. Get a flu jab
It’s not glamorous, but it’s still the best defence. The flu vaccine trains your immune system to recognise and fight the virus, significantly reducing the risk of severe illness. Check online to find out which pharmacies offer these closest to you.
2. Supplement with Vitamin D
Between October to March, most of us in the UK aren’t getting sufficient Vitamin D from the sun, and dietary sources usually aren’t sufficient. Vitamin D is essential for normal immune function, so consider a daily 10mg supplement of Vitamin D3 during the darker months, as recommended by the NHS.
3. Crush some garlic
Did you know that when garlic is crushed (e.g., with a knife), it releases allicin. Allicin is a compound linked to antimicrobial and immune-supportive effects. Regularly using fresh garlic in your food (bonus points if consumed raw) may help your body fend off common respiratory infections1.
4. Boost your berry intake
Blackberries, blueberries and blackcurrants are rich in flavonoids - natural plant compounds that may support immune responses. A review of studies found that people who consumed more flavonoid-rich foods were about 30% less likely to catch a cold or flu-like illness2.
5. Drink your green tea
Green tea contains catechins, a type of antioxidant studied for antiviral properties. One trial found that people taking green tea extract were about three times less likely to catch the flu than those taking a placebo3. In this study, they were consuming roughly the equivalent of three to four cups of green tea a day, but even a lower intake of one cup a day may confer some benefits.
6. Consider a live bacteria supplement
Clinically studied strains such as Lactobacillus rhamnosus LGG® and Bifidobacterium lactis BB-12® have been shown to reduce both the number and severity of respiratory infections4-5. But remember, not all probiotics are created equal. Look for products containing the right strain, at the right dose, supported by strong clinical evidence.
7. Manage stress and prioritise sleep
Long-term stress raises cortisol, which can weaken immune responses. Try to carve out time for rest, gentle exercise, or whatever helps you unwind. And don’t underestimate the power of seven to nine hours of good-quality sleep!
8. Stay hydrated
Water keeps your mucous membranes - your body’s natural first line of defence - moist and functioning properly. Warm drinks can also help keep you comfortable and soothe a sore throat.
9. Eat more fibre
Most of us in the UK could do with increasing our fibre intakes, with recommendation set at 30g per day for adults in the UK. Eating a wide range of fibres support your immune system (remember 70% of your immune system lives in your gut) and can reduce inflammation, which may help your body handle infections better.
Support: what to do if you already have a cold or flu
1. Honey for cough relief
If your throat feels raw and irritated, a spoonful of honey has been shown to help. A study has shown that honey can calm a cough as effectively as some over-the-counter syrups6 (but avoid giving honey to children under one year old).
2. Keep up your Vitamin C and flavonoids
Nutrients like Vitamin C and flavonoids won’t stop colds from developing, but they can make symptoms milder and shorter. Think bright fruit, colourful vegetables, and plenty of herbal or green tea for extra fluids.
3. Don’t push through
Your body heals best when it’s not multitasking. Take it as permission to slow down in any way that you can. Extra rest gives your immune system the energy it needs to recover efficiently.
4. Know when to call for help
If your symptoms persist, worsen, or affect your breathing, it’s time to speak to a healthcare professional. Most colds clear up within a week, but flu can sometimes lead to complications, especially in vulnerable groups.
For more tips, do’s and don’ts of managing the common cold, click here.
Takeaway message
There’s no silver bullet for avoiding winter bugs, but good nutrition, hand hygiene, hydration, stress management and an annual flu jab can help tip the odds in your favour.
References
1. El-Saadony MT, Saad AM, Korma SA, Salem HM, Abd El-Mageed TA, Alkafaas SS, Elsalahaty MI, Elkafas SS, Mosa WFA, Ahmed AE, Mathew BT, Albastaki NA, Alkuwaiti AA, El-Tarabily MK, AbuQamar SF, El-Tarabily KA, Ibrahim SA. Garlic bioactive substances and their therapeutic applications for improving human health: a comprehensive review. Front Immunol. 2024 Jun 10;15:1277074. doi: 10.3389/fimmu.2024.1277074. PMID: 38915405; PMCID: PMC11194342.
2. 307.Somerville VS, Braakhuis AJ, Hopkins WG. Effect of Flavonoids on Upper Respiratory Tract Infections and Immune Function: A Systematic Review and Meta-Analysis. Adv Nutr. 2016 May 16;7(3):488-97. doi: 10.3945/an.115.010538. PMID: 27184276; PMCID: PMC4863266.
3. Matsumoto K, Yamada H, Takuma N, Niino H, Sagesaka YM. Effects of green tea catechins and theanine on preventing influenza infection among healthcare workers: a randomized controlled trial. BMC Complement Altern Med. 2011 Feb 21;11:15. doi: 10.1186/1472-6882-11-15. PMID: 21338496; PMCID: PMC3049752.
4. Rautava, S., et al. (2009) ‘Probiotics and the immune system’, British Journal of Nutrition, 101, pp. 1722–1726.
5. Smith, T.J., et al. (2013) ‘Effects of probiotics on immune function’, British Journal of Nutrition, 109, pp. 1999–2007.
6. Abuelgasim H, Albury C, Lee J. Effectiveness of honey for symptomatic relief in upper respiratory tract infections: a systematic review and meta-analysis. BMJ Evid Based Med. 2021 Apr;26(2):57-64. doi: 10.1136/bmjebm-2020-111336. Epub 2020 Aug 18. PMID: 32817011.
Written by Rachel Redman - Registered Dietitian
Reviewed by Dr Pippa Gibson - Registered Nutritionist
