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Mushrooms - The 'Women's Health' website says that mushrooms have been scientifically linked to a boost in the immune system as they activate the cells that fight inflammations.

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Wholemeal cereals - Swap processed cereals for wholemeal ones, as they'll help your body protect itself against external attacks.

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Reducing stress - Stress can alter your mood and cause depression and anxiety, which directly affect the immune system, raising the chances of developing illnesses.

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Listening to music - This simple, enjoyable habit can be a great way to lower the cortisol levels which in turn boosts the immune system.

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Meditating - A great way to reduce stress levels is to meditate daily.

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Cold shower -

Finishing off your shower with cold water helps your body resist colds and flu.

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Nature - Spending time in nature and breathing fresh air helps your physical and mental health.

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Working out - Regular exercise directly benefits your immune system especially when you're older.

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Vitamin C - It is the most important nutrient for the immune system as it increases the production of cells that fight infections.

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Vitamin E - Vitamin E also stimulates the production of cells that fight germs and bacteria and protect the body against environmental contaminants.

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Carotenoids - They're rich in beta-carotene and can be found in foods like apricots, peaches, watermelon, corn, turnip, cabbage, potato, beet, broccoli and asparagus. These foods also contain antioxidants, which help repair cells damaged by free radicals.

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Selenium - Selenium can be found in tuna, meat, wholemeal cereals, nuts, among others. The fiber in those ingredients also helps the body get rid of toxins with the help of the liver, boosting the immune system.

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Zinc - Zinc can be found in dairy products, nuts, seafood, red meat, beans and wholemeal grains. It is really important when it comes to improving the development of T cells, which are vital in identifying antigens and informing the immune system about the presence of harmful substances in our body.

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Sushi and sashimi - Salmon sushi is anti-inflammatory and rich in carotenoids.

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No excessive sun exposure -

It's important to get vitamin D from the sun, but in excess it can cause skin aging and weaken the immune system.

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Vitamin A - Besides strenghtening the immune system, vitamin A also helps preserve your teeth, skin, and bone tissue. It also stimulates eyesight.

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Sleeping properly - Resting is vital for your body and mind. Try to sleep at least six to eight hours every night, as the immune system produces more cells during that period.

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Cut off the booze - Alcohol contains metabolites called aldehydes, which harm the immune system and make the body more vulnerable to diseases.

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No more cigarettes - Tobacco has a similar effect to alcohol as it also affects the immune system and increases the chance of developing breathing problems, such as pneumonia and bronchitis.

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Laugh more - Many studies have linked laughter to a growth in antibodies.

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Berries - Blueberries, raspberries and blackberries are some of the most antioxidant-rich foods and should be a part of your daily diet.

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Coconut and coconut oil - Coconut is a great source of lauric acid, a type of fat that is converted into monolaurin, which has antibacterial, antiviral and antifungal properties.

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Garlic - When eaten raw, garlic's antimicrobial qualities are one of the best foods for boosting the immune system.

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Dark chocolate and red wine - In small quantities, this combo provides antioxidants that reduce inflammations.

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Ginger and saffron - They both have anti-inflammatory properties.

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Sexual life - A study by US University Wilkes University analysed the sexual habits of 111 university students and found that the ones with the most active sexual lives had a higher level of immunoglobulin A in their saliva.

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Tea - A study released by the Proceedings of the National Academy of Sciences showed that some substances found in tea can help achieve a quicker immune system response.

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Coffee -

It is also important to limit the amount of coffee consumed because the acidity in it makes it harder for the intestine to absorb nutrients.

See also: The widowhood effect, and the famous figures who suffered from it

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