Ever wondered why some people seem to get all the colds, every winter? Our guest blogger Rebecca Goodyear explains how your immune system works, why it gets run-down, and how you can super-charge your immunity this winter and prevent those dreaded colds and flu.
Your best defence
Your immune system is a complex system of cells, tissue and chemicals that make up your body's mechanism to protect you from infection and disease. There are a few important aspects of immunity you should understand.
Firstly, immunity can be “innate” or “acquired.” An innate response is one that is non-specific to the infection the immune system is responding to, and kicks in almost immediately after the pathogen invades the body, whilst an acquired response is specific to the infection and can take several days to come into effect.
Immunity can also be “passive” or ‘active.” Passive is where our bodies are protected against infection even though our immune system has not responded to the virus. This type of immunity may be passed to us from our mothers in the form of antibodies via the placenta or breast milk. Active immunity is given to us via a vaccine or exposure to an infectious disease.
But beyond this complexity, the most important thing to understand about your immune system is that its function is dependent on several vitamins, minerals and other nutrients. So whether you are activating a rapid fire response (innate immunity), or calling up some memory of a previous infection so you can defend yourself better this time around (acquired immunity) you need the nutritional foundation to protect yourself and get the bug, before it gets you.
Why colds & flu in winter?
Winter is traditionally known as the cold and flu season, but what is the reason behind this? It's down to a number of external factors. Firstly, in the winter months we tend to spend a lot more time indoors, in closed air circulation areas in close proximity to others. This means that any infections or viruses carried are much more easily spread. Another reason is that many viruses thrive in the slightly cooler climate. Influenza for instance is most stable at 5 degrees Celsius. Finally the change in humidity also affects the likelihood of infection. Most viruses are spread through the air on water droplets, and the drier the environment, the more time the droplets carrying the virus hang around in the air, opposed to a humid climate where the water molecules are attracted to each other and fall to the ground before we have a chance to breathe them in.
The change in our diet from the winter to summer could also be partially responsible for our susceptibility. In the summer months we are automatically more inclined to eat fruits, salads and a more varied diet whereas in wintertime we may tend to reach for the sugary, salty snacks, comfort eating, as well as stocking up on stodge at meal times. Also, the tendency to cook vegetables in winter opposed to eating them raw means much of the nutrient content is lost. As well as still trying to incorporate raw, colourful vegetables into your diet and including fruit, cook your vegetables in ways that cause the least damage to their nutrient content, namely steaming, grilling and roasting.
But perhaps most important of all, there is very little sun in winter, and what little we do get we are unable to synthesise vitamin D from so vitamin D deficiency is much more common in the winter months. Some scientists think this is the main reason for flu outbreaks, and several studies have found vitamin D supplements can prevent infections in winter.
So, ensure you are eating a diet rich in high quality protein, as it has been shown that when bodies lack protein they lose their ability to make antibodies, and immune cells become depleted. It's also important to eat a vitamin-rich diet, all vitamins play their part in immunity in one way or another, be it vitamin C promoting phagocyte function and supporting T-cell function, or vitamin E supporting a healthy inflammatory response. Minerals also play their part in our immune systems, in particular zinc - a potent immuno-stimulant and a deficiency in it has been shown to suppress T-cell function – along with iron, copper, chromium, selenium and manganese. Antioxidants and phytonutrients found in colourful fruits and vegetables are also important in supporting the immune system.
Super-nutrition for cold and flu prevention
We can supplement our diets to ensure we are getting the aforementioned nutrients – a multivitamin and mineral, ensuring that levels of B and C vitamins are high, or failing that taking a separate supplement that contains these, you can find B complex supplements combined with vitamin C. You may also wish to choose a vitamin D supplement, as in the wintertime the sun is not strong enough for us to naturally create vitamin D. Our stores last about 3 months from summer, which leaves us with around another 3 months where we could be deficient.
There are some natural remedies that you may wish to consider taking before falling ill to boost your immunity -
- Elderberry – powerful actives in these berries have an incredible effect in the body - preventing flu viruses entering the cells of the body. Elder is also beneficial for treating sore throats and infections.
- Astragalus – has antibacterial and anti-inflammatory properties and protects and supports the immune system and is particularly effective at preventing colds and upper respiratory infections
- Garlic - has antiseptic, antifungal and nutritive properties. It is a natural detoxicant protecting against bacterial and viral infections.
- Mushrooms, such as Shitake, Reishi, Cordyceps and Turkey Tail - it is actually more effective to take a blend of mushrooms than one individually, as it is easier for pathogens in your body to adapt and become resistant to one mushroom than to several. Also, each mushroom species has a unique arsenal of anti-infective and immunomodulating agents, such as Polysaccharides, Glycoproteins, Ergosterols (steroid-like compounds that create vitamin D in sunlight) and Triterpenoids. Shitake possesses antiviral (including the common cold), antibacterial, and antifungal effects; Reishi helps with immune system up-regulation; Cordyceps boosts the overall wellbeing of the body, and detoxifies the body, making it the last place disease-causing organisms want to dwell; Turkey tail - polysaccharides in this mushroom have been found to enhance the immune system of cancer patients.
- Echinacea – the root of the plant is anti-inflammatory so limits symptoms of cold and flu by reducing mucus production, whilst the aerial part of the plant is anti-viral.
- Propolis - contains proteins and compounds that have the ability to alter and regulate the immune system, and which possess antibacterial and anti-viral benefits.
- Manuka Honey – offers broad spectrum protection against a variety of infectious organisms including bacteria, microbes, viruses, fungi and protozoa. When buying manuka check the Unique Manuka Factor, or UMF, it should be between 10 and 16 for it to be considered a medicine.
- Gingko Biloba – works by improving blood circulation and has an anti-inflammatory effect in the upper respiratory system
- Ginseng – Korean Ginseng has been shown to increase the active response of the immune system in people suffering from bronchitis, whilst Siberian Ginseng has been shown to boost the number of functioning immune system cells
- Vitamin D: at least 60% of people are vitamin D deficient in the UK, and this is worse in winter. Optimal vitamin D is essential for protection against infections and can reduce cold & flu frequency an duration. Adults should take 2000IU daily through winter.