Winter brings more than just colder days – it’s prime time for colds and flu too. While we can’t totally avoid every bug going, you can give your immune system the support it needs to fight back effectively. Here’s what’s proven to boost your immune system this winter.

Why does your immune system need extra support in winter? Winter months are the perfect combo of immune-zapping conditions: cold, dry air damages the protective mucus barriers in your nose and throat, making it easier for viruses to take hold; more time spent indoors in close proximity to others ensures germs spread quickly; and lower levels of Vitamin D (aka the sunshine vitamin) has a direct effect on our immune function.

So with the ideal conditions for cold and flu lurking around in the winter months, what can you do to boost your immune system?

1. Prioritise quality sleep

Sometimes it’s easier than it sounds, but sleep is seriously restorative – especially for your immune system, it’s when it does some of its most important work. During deep sleep, your body produces and releases cytokines, proteins that target infection and inflammation.

Research from University of California San Francisco shows that those of us who sleep fewer than six hours a night are four times more likely to catch a cold than those who sleep seven hours or more. The sweet spot is 7-9 hours’ a night, with consistent wake and sleep times even on the weekends.

To maximise your shut-eye, keep your bedroom cool (around 18-20°C), dark and quiet. Avoid screens for at least an hour before bed, as blue light can disrupt your natural sleep cycle.

2. Check your vitamin D levels

Many people become deficient in this hard-working vitamin when sunlight exposure is limited during the winter months. In fact, vitamin D acts more like a hormone than a vitamin, playing a critical role in immune function: helping to activate the T cells, which identify and attack pathogens.

If you’re constantly succumbing to circulating lurgies, consider getting your vitamin D levels tested. Experts recommend maintaining blood levels above 50ng/mL and if you’re below this, you can supplement with vitamin D.

During autumn and winter the NHS recommends everyone should take a daily vitamin D supplement of 10 micrograms (mcg)/400 IU (including children from the age of one).

It’s difficult to get enough vitamin D from diet alone during winter months but you should still include vitamin-D-rich food sources on your plate, including fatty fish like salmon and mackerel, egg yolks, and fortified foods.

3. Eat smart

About 70% of our immune system is in our gut, making what you eat a crucial part of the immunity puzzle. Focus on whole foods rich in immune-supporting nutrients and swerve high-sugar, processed foods.

Pile your plate with colourful fruit and vegetables, to guarantee a variety of different antioxidants and phytonutrients. Include citrus fruits, bell peppers and broccoli for vitamin C; oysters, beef and pumpkin seeds for zinc; sweet potatoes, carrots and leafy greens for vitamin A; and Brazil nuts and seafood for selenium.

Don’t overlook the importance of protein in your body’s immune response; it helps to build immune cells and antibodies so add high-quality protein sources to each meal.

Finally, support your gut health with beneficial bacteria from fermented foods like yoghurt, kefir, sauerkraut and kimchi.

4. Consider supplements and herbal medicines

There’s no disputing that a healthy diet needs to be at the top of your cold-fighting list, but some supplements are proven to support your immune system when you need it most.

Vitamin C may reduce the duration and severity of colds, although it won’t prevent them entirely. Aim for a dose of 200mg per day. Zinc has also been shown to shorten the duration of illness when taken within 24 hours of symptoms starting.

Stock up on HRI Coldcare to get both of these vitamins combined with echinacea root (equivalent to 338-450mg of echinacea purpurea), which helps to relieve the symptoms of colds and flu to help you tackle them head on.

5. Move your body regularly

Did you know, moderate exercise actually boosts your immune system by promoting good circulation, allowing immune cells to move through your body more effectively. It also reduces inflammation and helps immune cells regenerate regularly.

But keep things moderate – activities like brisk walking, cycling and swimming for 150 minutes a week is the sweet spot, and overdoing it with intense, prolonged exercise can actually have a negative effect on your immunity, suppressing it instead of supporting it.

6. Drink more water

Another key part of your body’s immune system is the lymph, which carries white blood cells and other immune cells throughout your body. Water helps produce lymph, so staying hydrated is essential.

Optimum hydration also keeps the mucous membranes in your respiratory tract moist, which makes them more effective barriers against pathogens. Aim for at least eight glasses of water daily, and more if you’re active – herbal teas count towards this.

7. Reduce your stress levels

It can be easier said than done, we know, but chronic stress is one of the most significant immune suppressors. When you’re stressed, your body produces cortisol, which can reduce the effectiveness of your immune system over time.

Even five minutes of meditation mindfulness and deep breathing exercises a day can help to reduce stress hormones and improve immune markers.

When it comes to boosting your immunity this winter, the key is to start today and be consistent. A long-term approach to wellness and supporting your immune system is the most effective thing you can do. So, if you need to add lots of brightly coloured veggies to your shopping trolley, or stock up on cold and flu-fighting supplements there’s no better time to do it.