The immune system starts with the protective barrier of the skin. Inside the body it is made up of a network of cells - such white blood cells, antibodies IgA, IgE, IgG and IgM, tissues and organs (such as the thymus gland, lymph glands and the spleen) that work together to protect the body.
Gut function – the barrier from the outside: The gastro-intestinal (GI) tract is made up by the intestinal epithelium that forms a barrier against the penetration of microbes. Cells of the small intestine have a mucus coating that interact with and trap bacteria and act as microbial sensors by secreting certain white blood cells in response to bacterial entry. Defects in this barrier function allow pathogens to enter the blood stream.
Immune systems support Low immunity can be due to a wide variety of factors ranging from having a poor diet, being overweight, not managing stress, to sleeping poorly and having a compromised digestion. Your first line of defence is to choose a healthy lifestyle, such as these points below.
· Exercise regularly – 3 x 30 minutes a week at least.
· Maintain a healthy weight.
· Control your blood pressure – eat less salt/sodium.
· Get adequate sleep – 8hrs/night.
· Drink alcohol in moderation <14 units/week.
· Avoid smoking
· Avoid infection - wash hands frequently and cooking meats thoroughly.
Nutritional Recommendations: A healthy diet should provide you with the nutrients you need to maintain a healthy immune system. Energy intake (calories) affects immune activity. Undernourished people are at greater risk from infections, whilst excessive energy intake (calories) may also compromise the immune system's ability to fight infection with its effect on inflammation.
Eat the rainbow: Enjoy a diet rich in a wide variety of plants of assorted colours to ensure a diverse daily intake of immune-supportive vitamins, minerals, phytonutrients, and fibre that provide the essential nutrients listed below.
Support the microbiome: Diverse and abundant colonies of beneficial bacteria are living in the gut, together with a healthy gut lining, are essential to our immunity. They provide us with a first line of defence against pathogens and help to balance and strengthen the immune system. Include 25-30 different plant foods a week!
Reduce inflammation: We should minimise pro-inflammatory foods (e.g., processed foods, sugar, sweeteners and alcohol) and maintain a healthy weight, as inflammation compromises the gut and immune function. Increase intake of wholefoods oily fish, fruits, vegetables, nuts, and seeds - protective against immune dysfunction and chronic inflammation.
Carbohydrates: supply the immune system with energy so that it can work better and fight disease. High fibre foods, like complex carbohydrates help to clean the gut and support its integrity. brown rice, quinoa, barley, buckwheat, oats, pulses, and starchy vegetables. Try to avoid simple sugars and processed carbohydrates, such as sugar, honey, sweets, molasses, white bread / pasta products, cakes, pastries, biscuits, pies etc.
Proteins: make enzymes, which help the immune cells kill germs, viruses, bacteria etc and keep the GI tract healthy. Proteins are comprised of amino acids – the precursors to neurotransmitters – that help to modulate immune functions. Choose chicken, turkey, lean red meats, eggs, and fish, or soya, tempeh, mycoprotein (Quorn), nuts and pulses.
Fats: They serve as fuel for the immune cells and omega 3 fats help to reduce inflammation. Unhealthy fats can cause inflammation and obesity - triggering an overactive and compromised immune system. Diets high in animal saturated fats depress immune responses, whereas diets lower in these fats increase and strengthen immune activity. Omega-3 fats: salmon, mackerel, herring, tuna (fresh), anchovies, trout, and sardines. Vegetarian / vegan sources: flax/hemp seeds (cold pressed), walnuts, pumpkin/chia seeds and marine algae.
Micronutrient immune support [can you please infographic some of the highlighted foods]
· Vitamin A supports the immune response and integrity of our digestive tract. carrots, squashes, broccoli, sweet potatoes, tomatoes, leafy greens and brightly coloured fruits.
· Vitamin D enhances the immune response and modulates inflammation. It is poorly available in foods – sunlight is the primary source. Supplement from September to March with at least 1000IUs (10mcg)/daily. Oil based vitamin D3 and K2.
· Vitamin C inhibits virus multiplication and improves immune cell functions. citrus fruits, green peppers, broccoli, leafy greens, tomatoes, berries, and peas.
· Zinc inhibits the replication of viruses, boosts immunity and reduces the risk of respiratory infection. oysters, red meat, eggs, herrings, sunflower, pumpkin seeds, peanuts, and leafy greens.
· Selenium increases the antioxidant glutathione, and it also supports white blood cell and antibody production. fish, shellfish, Brazil nuts, wholegrains, pulses, leafy greens, chicken, tuna, and garlic.
· Beta-glucans stimulate the immune system by increasing ecretory IgA, which is one of our first lines of defence against infection. barley, oats and whole grains, Asian mushrooms: Reishi, Maitake and Shiitake, and seaweed or algae.
· Probiotic and prebiotics support the immune system and the correct functioning of the gut. Supplement if not obtained by the diet – not with sweet yoghurt drinks like Yakult. prebiotic: chicory, Jerusalem artichoke, garlic, onions, leeks – probiotics: bio-yoghurt, kimchi, natto, sauerkraut, tempeh, miso, kombucha, pickles.