By Lisa Salmon
Having a healthy immune system is vital for both children and adults – and what we eat plays a major part in this.
Paediatric infectious diseases expert Professor Kirsty Le Doare from St George’s, University of London, explains that the nutrients we get from food and our good gut bacteria, which are affected by food, help modulate the immune system and keep its natural balance, helping to protect us from disease and infection.
“A healthy diet helps keep our immune system healthy and can help prevent or reduce the risk of immune-mediated diseases,” she says. “Malnutrition affects how the immune system works, and a poor, unhealthy diet that’s low in vitamins and minerals can have the same effect.”
“All of these nutrients are essential for other functions in the body, as well as supporting the immune system,” says British Nutrition Foundation (BNF) science director Sara Stanner. “And the best way to get all of these nutrients is to have a varied and balanced diet.”
But what should you be looking out for?
Found in: Eggs, cheese, whole milk, liver. The body can also make vitamin A from beta-carotene, found in dark green leafy vegetables, orange-coloured fruits and vegetables (e.g. carrots, melon).
Carrots are rich in beta-carotene which can be converted to vitamin A in the body – three tablespoons will provide children under 10 with all they need for the day, and a baked sweet potato can give teenagers and adults all the vitamin A (as carotene) needed daily.
Found in: Poultry, fish, fortified breakfast cereals, chickpeas, soya beans, some fruit and vegetables (e.g. bananas, avocados, green peppers), nuts and seeds.
A banana provides around a third of the vitamin B6 needed for a 4 to 10-year-old. A snack of walnuts (20g, or six halves) provides around 10% of the daily vitamin B6 requirement for teenagers and adults.
Found in: Meat, fish, milk, cheese, eggs, fortified breakfast cereals, fortified milk alternatives.
Two tablespoons of tuna in a sandwich can provide all the vitamin B12 a child needs for the day, and two poached eggs will provide all the daily vitamin B12 adults and teenagers need.
Found in: Citrus fruits, berries, kiwi fruit, green vegetables, cauliflower, peppers, tomatoes.
Five small steamed florets of broccoli will provide under 11s with the vitamin C they need for the day. A stir-fry with portions of sugar snap peas and red peppers will give teens and adults their required daily vitamin C.
Found in: Wholegrain breakfast cereals, wholewheat pasta, couscous, quinoa, shellfish, pulses, dried fruit.
Baked beans are an easy source of copper as are pulses used in soups, stews, and curries are good copper sources.
Found in: Oily fish, eggs, some fortified breakfast cereals, some fortified dairy and dairy alternative products.
Oily fish is a good source, so try a sardine Bolognese. Children between one and four years should be given a daily 10mcg vitamin D supplement all year, and older children should take a supplement in autumn and winter.
Found in: Green vegetables, chickpeas, oranges, berries, cheese, wholemeal bread.
Green veg are packed with folate, whether it’s peas, plenty of lettuce, rocket and spinach in salads, and pak choi in stir fries.
Found in: Red meat, pulses, nut butters and seed pastes like peanut butter and tahini, fortified breakfast cereals, wholemeal bread, dried fruit.
Vitamin C can help the body absorb iron, so try a glass of orange juice with fortified breakfast cereal.
Found in: Nuts and seeds (particularly Brazil nuts, cashews, and sunflower seeds, eggs, poultry, fish, shellfish.
Fish is a great selenium provider – teenagers and adults should be eating at least two portions of fish a week, one of which should be oily (e.g. salmon, sardines).
Found in: Meat, poultry, cheese, nuts and seeds, some shellfish (like crab and mussels), wholegrain breakfast cereals, wholegrain and seeded breads.
Lean beef mince is a good source of zinc, so favourites like chilli, meatballs and cottage pie will all boost zinc intake. Wholegrains are also a source of zinc so try wholegrain cereal or a cheese sandwich on wholegrain bread with plenty of salad.