Load up on vitamins C and D

Getting in the right nutrients is essential for optimum functioning of the body – including the immune system. Vitamin D and vitamin C are what to focus on: research by the World Health Organisation has shown that taking vitamin D supplements can reduce your risk of experiencing at least one respiratory infection, including the common cold, influenza or pneumonia, by a third. Other studies show that vitamin C suppresses the activation of viral genes so that cold viruses cannot survive in cells. Your best bet is to ensure you’re consuming a bit of citrus every day, whether that’s an orange at breakfast, a glass of freshly squeezed grapefruit juice mid-morning or a healthy lashing of lime juice over your curry in the evening.

Focus on a Mediterranean style diet

While the NHS recommends taking a vitamin D supplement, especially during the winter months, what we eat is also important. Dr Brewer recommends eating a Mediterranean style diet with plenty of fruit and vegetables, onions, garlic, oily fish and wholegrains, which she says can provide all the nutrients necessary to help support the immune system.

Stay active (but don’t over-exercise)

Other lifestyle tweaks you can make include staying active and prioritising exercise, which can neutralise the harmful effects of stress hormones. “Exercise should be non-competitive, so avoid over-training and marathons [to support immunity] as physical stress suppresses immunity and increases the risk of developing symptoms when exposed to a common cold virus,” Dr Brewer advises.

Sleep more

Finally, now’s the time to enjoy some well-earned rest. “During sleep, your body secretes hormones involved in fighting disease,” says Dr Brewer. “People who sleep for seven to eight hours have better immunity than those who are sleep deprived, and tend to live longer, too.”

Feeling run down? Here’s how a GP recommends supporting your immune system when it’s running low