We all know that eating badly has an effect on how you feel – too much reﬁned sugar and saturated fat can make you feel sluggish, for example – but the opposite is also true.
Picking foods that are high in immune- and energy-boosting nutrients can help you leave the cold remedies in the bathroom cabinet, and speed through winter with a smile on your face.
Food to avoid
Below we talk about a range of foods that boost immunity, here are some foods to avoid:
- Saturated fat and dairy products (May cause inﬂammation and therefore depress immune function).
- Coffee (Stimulates the pancreas to secrete insulin, and interferes with absorption of calcium, iron and magnesium and B vitamins).
- Reﬁned white ﬂour products (ie white bread and pastries).
- Reﬁned sugar products (eg sweets).
Foods that boost immunity
Nuts and seeds
Nuts are high in fat, but they’re generally ‘good fats’: polyunsaturated and monounsaturated. Nuts contain all the important fatty acids and are good sources of essential minerals such as magnesium, phosphorus, potassium, copper and selenium.
Meat, poultry and ﬁsh
Poultry is a good source of B12; turkey also contains potassium – which encourages the production of tryptophan – and zinc, which encourages wound healing. Beef is another good animal source of zinc.
Oily fish (sardine, salmon, trout, anchovy and mackerel) is the best source of Omega 3 fatty acids, which are called ‘essential’ fatty acids because we can’t manufacture them ourselves.
Omega 3 is anti-inflammatory and protects our heart, skin, eyes, brain and joints. Vegetable sources include nuts and seeds, particularly flax and hemp, but may not be as bio-available as fish sources.
Grains and pulses
Grains and pulses are an often underused nutritional resource, and while many grains (especially wheat and corn) are found in high proportions in our diet, we tend to take out the ‘good stuff’ by processing them and discarding the bran and germ (the outer layers), which contain insoluble fibre and nutrients.
Oats are a particularly good source of B vitamins and minerals, and have a low level of gluten. Plump for whole grains and brown rice. Lentils are a rich (and virtually fat free) source of fibre and protein, plus they contain tryptophan and iron.
Fruit and vegetables
Some mushrooms (reishi, shiitake and maitake) help build white bloodcells and contain beta-glucans – as do yeast, oats and barley bran – which have been proven to modulate the immune system.
Bananas and carrots are good sources of B6 (also found in meats, eggs, wholegrains and nuts). Vitamin B6 assists in the release of glucose from glycogen and the metabolism of protein. Bananas also contain vitamin C and potassium (as do dates and papaya), which encourages the production of tryptophan, a precursor to seratonin (5-HT) which helps regulate mood and sleep.
The Allium family (garlic, onions, shallots, leeks and chives) have antibacterial, antiviral and antifungal activity, and contain high levels of sulphur, which has an anti-inflammatory effect.
Live yoghurt contains probiotics, beneficial bacteria that may boost immune function by balancing microflora in the gut, which aid digestion and promote a healthy immune response.
Black, green and white tea contain high levels of antioxidants – try to drink them instead of coffee. Even better, switch to herbal teas. Herbs such as echinacea, licorice, ginseng, astragalus, sage, elderberry and hyssop have all been shown to support the immune system, and can be used in cooking or taken as teas or tinctures. Add as many herbs and spices to your cooking repertoire as you can: they are a rich source of trace minerals and nutrients.