Tweaking your diet during the winter months will help to bolster your defences and improve your chances of recovering from seasonal coughs and colds, writes nutritionist Louise Pyne

While exercise helps to stimulate the immune system, more intense sessions could actually weaken it short-term. This means if you’re training for a triathlon, marathon or any other endurance race your immune system could take a hit, making you more susceptible to bacteria and viruses.

During gruelling workouts, your body pumps out the stress hormone cortisol, which acts as an immune system suppressant – and the more intense your exercise, the higher your cortisol levels. It’s thought that these effects could last for around three days after your session finishes, which means that you’re more vulnerable to getting sick.

The good news is that by altering your diet you can also increase your body’s defence system to shield your body against potential invaders. Here are our favourite winter immunity boosters…

foods to boost immunity this winter Men's Fitness UK

It might not be your go-to snack on a cold winter’s night, but sauerkraut is packed with immune-boosting bacteria

Sauerkraut

Seventy per cent of our immune system is situated in our gut, and what makes immunity flourish is the trillions of bacteria that live there. Probiotic foods contain the good bacteria that your gut loves and fermented foods like sauerkraut are packed with a diverse strain of these gut goodies to help you avoid winter ailments.

A 50g serving of the tangy fermented cabbage can also reduce digestive symptoms like bloating and constipation, which could hamper your usual training schedule.

Garlic

Prebiotics are the foods that the healthy gut bacteria like to eat, and garlic is crammed with these antimicrobial properties that nurture gut health.

In order to get maximum prebiotic punch eat garlic raw or minced (rather than chopped) and lightly cooked, as the longer you cook the pungent bulb the fewer prebiotics it contains. You could add half a teaspoon of raw garlic to olive oil-based salad dressings to reap the benefits.

foods to boost immunity this winter Men's Fitness UK

Strawberries are loaded with vitamin C

Strawberries

Strawberries are the ultimate immunity booster for active people. They are rich in vitamin C which acts as a barrier against pathogens, helping to keep cells healthy.

This nutrient can’t be stored by your body, so you need to keep levels continually topped up eating vitamin C foods regularly.

Broccoli

This cruciferous vegetable helps to keep your liver happy. The liver is a key detoxification system of the body, and keeping detoxification in good working order will help to offset illness.

One portion of broccoli counts as two spears according to NHS guidelines, but the more the better – in order to keep levels high, aim for double that.

foods to boost immunity this winter Men's Fitness UK

Pumpkin seeds are rich in zinc and protein

Pumpkin seeds

These little seeds are high in zinc, which is needed to produce immunity-fighting white blood cells and fight inflammation to give bugs the boot.

They are also a source of protein to help feed muscles post-exercise. Top up levels by snacking on a handful of seeds between meals.

Salmon

Salmon is an all-round immunity-proofing food for gym-goers. It contains omega-3 fast acids which help to reduce the load on your immune system.

They also calm down inflammation by keeping cell membranes intact for healthy, pain-free joints. Try and include salmon in your diet twice a week.

Yogurt

For anyone leading an active lifestyle, yogurt is one of the best foods to add to your diet.

It’s packed with protein (a 150g pot contains over 6g) to nourish muscles, but more importantly it’s a rich source of probiotics, which help stop foreign microbes from doing damage in the body.

foods to boost immunity this winter Men's Fitness UK

Ginger contains antioxidants which help keep illness at bay

Ginger

There’s nothing that says winter quite like warming ginger, and this zingy spice is rich in antioxidants called gingerols which help to fight illness.

Down a ginger shot made with freshly squeezed lemon, one teaspoon of ginger root and one teaspoon of Manuka honey every day to keep immunity tip top.

Brazil nuts

Brazil nuts are high in the trace mineral selenium, which boasts antioxidant properties called selenoproteins to help keep cells healthy, by mopping up free radicals and bacteria that could leave you more prone to winter sniffles.

Snack on one tablespoon of the nut every day to keep selenium levels topped up.