As winter arrives, there’s a noticeable uptick in the quest for ways to stay healthy. Supermarkets are stocked with “immune-boosting” drinks, cold water swimming groups have become trendy, and social media is overflowing with advice on dodging seasonal illnesses. But amid all these remedies, it’s worth asking: how effective are they really? Can we even supercharge our immune systems?
Cold water swimming: A buzz, not a boost
Cold water swimming has gained a dedicated following, with enthusiasts firmly believing it wards off winter ailments. Professor Eleanor Riley, an immunologist, shared insights on BBC Radio 4’s Inside Health podcast, noting that the post-swim “high” isn’t a magical immunity boost; it’s just adrenaline and endorphins at work. “When you take blood samples before and after cold swimming, white blood cell levels do increase,” she explains. “But that’s simply because the body interprets the cold as a potential infection threat.” Those levels normalize quickly, indicating no real long-term increase in white blood cells.
Moreover, Riley highlights that part of what makes cold water swimming feel good is the community aspect. Feeling more “alert and connected” offers genuine physiological benefits. Another expert, Professor John Tregoning, emphasizes that the perks are often indirect; socializing outdoors can lower stress, which has its own health advantages. “It’s not just cold water that helps; you could experience similar benefits from activities like dancing or going for a run,” he suggests. Spending time in nature, after all, can lower blood pressure and stress hormones that undermine immunity. Dr. Margaret McCartney adds that while moderate exercise is known to help fend off viral infections, it’s not exclusive to cold swimming.
Kombucha: Interesting but little evidence
Fermented beverages like kombucha are often popular choices, touted for enhancing gut health, which in turn is believed to bolster immunity. Dr. McCartney approaches this topic with caution: “While many theories suggest a diverse microbiome is beneficial, we lack robust evidence to advise kombucha as a health strategy.” Tregoning notes that while the microbiome does fluctuate during infections, it generally returns to its baseline afterwards. Dr. McCartney concurs, stating that while kombucha’s role in microbiome health is intriguing, there’s no strong evidence linking it directly to immune boosting.
Supplements: Just expensive urine
Vitamin C has long been marketed as a must-have for winter, but Dr. McCartney argues there’s not enough evidence to back its effectiveness against colds. Similarly, she views multi-vitamins as little more than “expensive urine.” Vitamin D is a bit of a different story, showing some evidence for reducing respiratory infections. However, she points out that only individuals with low Vitamin D levels or pre-existing respiratory conditions are likely to see benefits. Given that many in the UK are deficient, Tregoning suggests getting outside for winter sunlight as a natural remedy.
Vaccinations: The only boost that works
As for more trendy options like turmeric shots, ginger drinks, and nasal sprays, Dr. McCartney stresses they don’t effectively enhance your immunity. Tregoning adds that for blocked noses, a simple saline spray, which is just salt and water, does the trick by thinning mucus and easing inflammation. When it comes down to it, all three experts agree: only vaccinations genuinely bolster the immune system. Riley advises getting the flu shot, which takes about a week to ten days to show effect.
While you might not find the dramatic immune boosts often advertised in winter wellness trends, maintaining your immune health is still achievable. Experts recommend avoiding smoking, managing a healthy weight, ensuring consistent sleep, and engaging in activities that reduce stress. Dr. McCartney also highlights the importance of washing hands properly and spending time in well-ventilated areas to further decrease your risk of catching colds.
