"Immunonutrition" - Give Your Immunity a BOOST!
How can your boost your immune system to help you reduce your risk of infection this winter!
At this time of year, it is a good idea to prepare your immune system so that it stays strong and healthy throughout the winter. Your immune system fends off disease and protects you from bacteria, viruses and other microbes.
The immune system can be broken down into the innate immune system and the adaptive immune system. The innate immune system is our first line of defence and it will respond immediately by preventing the movement of pathogens throughout the body. The adaptive immune system is our second line of defence and specific to the pathogen it is facing where it will attack and destroy said pathogen.
The immune system is our defense system and is made up of entire organs and vessel systems like the lymph vessels, but also of individual cells and proteins. So the immune system is not a single entity, it is a system and in order to function it needs to be balanced and in harmony.
Research in to the effects of age, diet, psychological stress, exercise etc. is still being explored for humans. However there are healthy habits that we can adopt in order to give our immune system the upper hand.
7 Healthy Habits to Boost your Immune System
Eat a plant based diet, high in vegetables and fruits
Exercise regularly
Don’t smoke
Go to bed early
Drink in moderation, if at all.
Wash hands
Adopt stress management techniques
NUTRITION
For a healthy immune system to be maintained, it requires good, regular nourishment.
Nutrients that have been demonstrated to be important for optimal function of our immune systems include essential amino acids (think protein), zinc, iron, selenium, folic acid, copper, vitamins A, B6, B12, C and E. Deficiencies in these micronutrients may change how the immune system responds.
Micronutrient malnutrition, where a person is deficient in various esential trace minerals and vitamins that you can get from your diet or in supplementation form can be common in the elderly. This may be due to a lack of nutrient dense nutrition and variety in their diet as well as a decreased ability to absorb nutrients. This needs further reserach in humans but incorporating a varied plant based diet in to your daily nutrition is a good idea.
Essential Amino Acids - A deficiency of dietary protein or amino acids has long been known to impair immune function and increase our susceptibility to infectious disease. Studies have shown that not just our total protein intake is important, but also specific dietary amino acids (glutamine, glutamate, and arginine, methionine, cysteine and threonine) are important for the optimisation of our immune function. Amino acids are important in activating the response of our immune cells as well as the production of our antibodies. Animal protein (meat, fish, eggs, milk and cheese) sources contain the highest levels of protein as well as the full range of essential amino acids required. Lower levels of protein can also be found from lentils, beans, nuts and seeds.
Zinc - research has shown that zinc is important for the maintenance and development of immune cells for both our adaptive and inate imune system. Shoujld we have a deficiency of sinz, our immune cells are affected, potentially leading to impaired formation, activation and maturation o our immune cells and therefore our immune system. Whilst supplementation of zinc is possible, food sources of zinc include oysters and beef, pork, shellfish, seeds, nuts and wholegrains.
Iron - iron is said to be the most common micronutrient deficiency worldwide. Research has shown that iron deficiency exceeds 50% in developing countries and is usually due to to inadequate nutrition. Iron is a very important element for the normal development of the immune system, particularly our innate immunity. Its deficiency appears to affect the capacity to have an adequate immune response. Good food sources for iron include liver, meat, beans, nuts, dried fruit (apricots), wholegrains. To improve the absorption of iron consume alongside vitamin C.
Selenium - Studies have shown that selenium is an essential micronutrient which has a crucial role in the development of immune responses. The immune system relies on adequate dietary selenium intake, without which, may lead to increased inflammation or even immune-related diseases. Brazil nuts are one of the best sources of selenium, just 1-2 every day will give you your daily requirement. They are best soaked overnight and then gently roasted the next day so maximum effectiveness. Other food sources of selenium include tuna, oysters, pork, beef, chicken, tofu, whole wheat pasta and mushrooms.
Copper - the link between copper and the function of the innate immune system has been looked at for a long time. Diets that are deprived of copper, typically increased the risk of infection and the duration of infection. Foods sources that have very good levels of copper include liver (beef), oysters and sesame seeds. Decent levels of copper can also be found in potatoes, cashews, mushrooms and chickpeas.
Vitamin A - This vitamin can be in two forms, retinoids or beta carotene. Rentinoids are known as pre-formed vitamin A, whereas beta carotenes are converted by the body into vitamin A. Vitamin A is important for many functions of our body but it is also known as an anti-inflammation vitamin because it has an important role in enhancing immune function. Vitamin A helps with the development of the immune system as well as helping the immune cells to respond to infection from pathogens. Good food sources of retinoids are animal products such as beef liver, shrimp, eggs, fish, butter and cheddar cheese. Sources of beta carotene will be plant sources (think mainly orange foods) such as sweet potatoes, pumpkins, carrots and squash but also spinach, mangoes and turnip greens.
Vitamin B6 (pyridoxine) - this vitamin has many important roles within the body, including helping the body to absorb vitamin B12, to make important neurotransmitters such as serotonin, make red blood cells as well as immune cells. Studies have suggested that vitamin B6 deficiency can cause a sub-optimal immune response. Ensuring optimal levels of vitamin B6 has been shown to benefit our immune system. Great sources of vitamin B6 include chicken, turkey, pork and fish. Vitamin B6 can also be found in wholegrains, starchy vegetables and some non-citrus fruits.
Vitamin B12 (cobalamin) - vitamin B12 is important for the production of our white blood cells which are essential for optimal function of our immune. A deficiency of B12 can lower our immunity as it it facilitates the production of immune cells as well as maintains numbers of others. The best sources of vitamin B12 include meat, fish and dairy products.
Vitamin C - vitamin C is an important nutrient for many of our bodily functions. It is an anti-oxidant, a cofactor and contrinbutes to both immune systems by supporting various cellular functions within them. For those with a vitamin C deficiency, their immunity will be impared and they will be more susceptible to infections. It isn’t difficult to enjoy foods rich in vitamin C, these include broccoli, brussel sprouts, red peppers, dark green leafy vegetables, kiwi, blackberries, strawberries and oranges.
Vitamin E - studies have shown that vitamin E enhance our immune response as well as increases our resistance to infections. The major food sources of vitamin E tend to be vegetable oils with wheatgerm oil containing the highest amounts. Nuts are good sources as well. Soybean, sunflower, corn, walnut, cottonseed, palm contain high amounts.
OTHER IMPORTANT NUTRIENTS
Vitamin D
Vitamin D may also help to imorve our immunity and reduce the frequency and severity of colds and flu.
Our main source of vitamin D comes from the sunshine. Ideally we need to expose our skin to sunshine every day for 20 minutes but with sunshine being sparse in the UK many of us are at risk of a vitamin D deficiency.
The advice from Public Health England (PHE) states that everyone should take a daily vitamin D supplement during autumn and winter just to maintain a good level.
Beta Glucans
Beta Glucans are naturally occuring pollysaccharides (sugars) which are produced by bacteria, yeast, fungi, and many plants. Studies have suggested that beta glucans activate some of our immune cells. They have been shown to protect against infection by bacteria, viruses, and pathogenic as well as prevents cancer promotion and progression. Beta-glucans are able to enhance the function of macrophages and natural killer cells within the immune system. The following foods contain high levels of beta-glucans barley fiber.
maitake, reishi and shiitake mushrooms
oats and whole grains
seaweed
algae
Gut Health
Gut health and how your immune system functions is central to preventing illnesses, in fact 70% of your entire immune system resides in your gut!
Your gut bacteria provide essential health benefits by balancing your immune system. Your gut bacteria help your immune system’s T cells to develop and teach them the difference between a foreign substance and the body’s own tissues.
Therefore the health of your gut is very important for your your immune system responds. If you have an overgrowth of pathogenic bacteria if may lead to your immune system attacking your own cells and not forgeign one. Studies have shown that changes to your gut bacteria can cause a dysregulation in your immune system, potentially leading to autoimmune disorders!
Beneficial gut bacteria are able to interact with the epithelial cells that line the gut as well as the cells of the immune system in order to help balance your immune responses and protect the gut from unwanted inflammation.
Your gut also decides what passes through the gut lining into the blood and what doesn’t. If the lining of your gut wall isn’t healthy and develops larger gaps (leaky gut) then larger particles or antigens can pass through causing an immune response potentially laeding to autoimmune disease, causing inflammation and pain.
One of the best ways to improve your immunity is to heal your gut!
EXERCISE & SLEEP
Just like a healthy diet, exercise also adds to general good health and therefore may contribute to a healthy immune system.
Exercise may also improve our immune system more directly by promoting circulation, which will help any immune cells etc. to move through the body efficiencly enabling them to do their job.
Sleep is just as important as exercise, if not more. Sleep is important for the proper functioning of the immune system. Studies have shown that people who don't get good quality sleep or are deprived of sleep are more likely to get sick when they are exposed to a virus, like the common cold. In addition, a lack of sleep can also affect your speed of recovery when you do get sick.
The immune system and the central nervous system communicates bidirectionally, they send signals through cytokines, neurotransmitters and hormones. Prolonged sleep deprivation encourages the production of pro-inflammatory cytokines, (clow grade inflammation) as well as a deficiency in the immune system. These both have a detrimental effect on your health. The National Sleep Foundation suggests that optimal sleep is between 7 and 9 hours every night. What you eat and drink can have a beneicial or negative effect on the quality of your sleep. Get in touch to discuss if this is someting that is affecting you.
It is also worth mentioning that prolonged stress also has a negative effect on our immune fucntion. When we are stressed, the body’s ability to fight off antigens is reduced. The stress hormone, cortisol, supresses the effectiveness of the immune system. It is a great idea to incorporate stress maangement techniques that resonate with yourself, in to your daily life. This could be breathing techniques, meditation, yoga, Pilates, reading, being outside with nature, whatever helps you to achieve a calming down effect.
To Summarise……
In order to help support your immune system, allowing it to function optimally and give you the best possible chance in avoiding viral and bacterial infections you want to try and adopt the following habits:
Eat a colourful and varied plant based diet with particular highlight to those foods that contain the micronutrients needed by the immune system.
Look after your gut - eat foods that help the beneficial bacteria to prolierate as well as those that protect the gut lining
Sleep 7-9 hours every night
Include moderate daily exercise
Incorporate daily stress management techniques
Avoid outside stressors that challenge your immune system such as alcohol, smoking and other toxins
Get outside, enjoy the sunshine at every opportunity
RECOMMENDED READING:
Essential Fatty Acids: Omega 3’s
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