1 Wild mushrooms

Contain more of the immunity-boosting antioxidant ergothioneine than any other food. They also boost natural germ-fighting cells and enhance energy, according to a US report.

2 Herring

Just 25g contains your daily amount of vitamin D, which is proven to improve immunity, support bones and help fight the winter blues. Its omega 3 fats also promote good blood circulation and reduce inflammation.

3 Apples

Contain the flavonoid quercetin, which can help those who are susceptible to viruses – and that includes athletes. They are also rich in soluble fibre and vitamin C.

4 Onions

Antioxidants, especially quercetin and sulphur, support the immune system and help the liver flush out toxins. Onions are also loaded with infection-fighting vitamin C and folate, which is needed to make new cells and boost immunity.

5 Garlic

Antifungal, antibacterial and antiviral properties fight off colds. The key ingredient is allicin, whose properties are more potent when the bulb is crushed and left to stand for ten minutes before cooking.

6 Beetroot

Soluble fibre helps to lower bad cholesterol and clear out harmful germs. Also turns your wee red, irrelevantly.

Try this hearty muscle-building pasta. It contains two of the above items – mushrooms and garlic – and is perfect after a tough winter workout.