Nutritionist Dr Sarah Schenker chooses the best fresh foods and health products to keep you fighting fit against illness.
Beef is a rich source of protein, particularly certain components known as amino acids which are required by the immune system. Glutamine is among the most important amino acids to immune cells. Studies on hospital patients and athletes (both of whom have compromised immunity) show that glutamine improves immunity and reduces the risk of infections.
All types of beef are a good protein source. The richest is salt beef, but only tuck into this if your blood pressure is normal and be careful not to exceed the daily limit of 6g of salt. The vegetarian option, soya bean products, contain all essential amino acids and glutamine.
You could also try: Chicken
Probiotic bacteria can help to reduce the risk of gut infections as well as easing the symptoms of conditions such as irritable bowel syndrome.
Research has shown that people who suffer from recurrent bowel infections have reduced numbers of the normal ‘friendly’ bacteria in their gut and an imbalance or overgrowth of the sometimes harmful bacteria that can cause gastric pain, bloating, diarrhoea and constipation.
You could also try: Probiotic drinks
Vitamin E is another crucial vitamin for a healthy immune system. It is present in the fat in your foods (or ‘fat soluble’). Whereas too much fat in the diet is a bad thing, too little could mean you’re missing out on vitamin E and other fat-soluble vitamins.
Olive oil is a great source of vitamin E and mono-unsaturated fats, which are good for your heart as well as your immune system. Use it in cooking and in salad dressings.
You could also try: Nuts and seeds
Pine nuts are a rich source of zinc. An adequate zinc intake helps to prevent infections in the gut and the respiratory system. But be careful not to overdo it with zinc supplements as they can suppress your immune system functions.
Eating a wide variety of foods and having a healthy diet is the best way to balance the zinc in your diet. But zinc supplements can be useful in boosting the immune system after a bout of prolonged illness.
You could also try: Shellfish
Echinacea is a natural antibiotic and infection fighter that helps to kill bacteria, viruses, fungi and other disease-causing microbes. The herb, originally a remedy from North America, stimulated immune cells and boosts their production of a virus-fighting substance called interferon.
Taking the supplement at frequent intervals – as often as every couple of hours during acute infections – is advisable, because its effects are relavtively short-lived.
Mangoes are a great source of vitamin C and beta-carotene, which mop up free radicals and prevent damage to cells that can initiate heart disease or cancer. When a mango is ripe, the flesh is easy to digest.
You could also try: Oranges or melon
Tests have shown pomegranate juice to be rich in antioxidants. They can neutralise damaging free radicals generated by a poor diet, pollution and cigarette smoke, all of which are implicated in heart disease, strokes, cancer and ageing.
The juice contains three times the antioxidant properties of red wine or green tea.
You could also try: Blueberries and blackberries
Sardines are a rich source of omega-3 fats, another crucial nutrient for cells of the immune system.
You could also try: Salmon and mackerel