It is still gloriously warm across much of New Zealand, so it may seem odd to be writing about winter…..but now really is the time to take a moment to make sure that you’re prepared for the coming cold and ‘flu season.
You all know the saying ‘prevention is better than cure’ but with so much advice available and much of it contradictory, it can be difficult to know where to start.
Well, I’ve long believed that the best way to start is to look at carrying out the most logical, simple things that you already know serve your general health, such as ensuring you get enough sleep, not over-doing it at work or play, eating well and managing your stress levels. If you know that you tend to be susceptible to colds and ‘flu or just want to ensure optimal health, then some additional nutritional and herbal medicine support may be really beneficial.
I love herbal medicine and there are so many great products and formulations available in the market place, but choosing the right one can be an overwhelming experience. To help you out I’ve made a list of my top 5 favourite (and evidence based) herbs and nutrients for building a strong immune system so you can keep well this winter.
Astragalus – Astragalus membranaceus – the root of this plant has been a mainstay of traditional Chinese medicine (TCM) for around two thousand years. Studies have discovered that astragalus stimulates the activity and responses of certain immune cells (namely marcrophages and antibodies).  It is thought that this mechanism is responsible for its immune enhancing capacity; in one study where the subjects were a group susceptible to the common cold, astragalus was able to provide preventative protection to the group. Additional to the direct effect on the immune system, Astragalus made my top 5 list as it is also adaptogenic – meaning that it increases the body’s resistance to physical, environmental and emotional stress. Best of all, there are no likely interactions with this plant and other medications, it is generally recognised as safe (GRAS) though it is recommended to avoid taking it when you have an acute infection – so keep it in the ‘preventative’ file for colds and ‘flu.
Echinacea – Echinacea angustifolia, E. purpurea – it would hardly be an immune article without mention of this well-known herb. Found in many immune products, Echinacea’s real strength lies in its ability to prevent the occurrence of common colds – though, it has also been shown to reduce the severity of symptoms as well. When choosing which Echinacea to use make sure you get one that uses the root of the plant – it can be a combination of E. angustifolia and E. purpurea or just one of these. If you choose a liquid form the characteristic ‘tingle’ is an indication of a good preparation (it’s the alkylamides that cause this). Echinacea is also GRAS.
Vitamin C – this is an essential vitamin that cannot be synthesised in the human body – meaning we must get it through our diet, luckily, it is abundant in fresh fruits and vegetables. During times of stress or infection our concentration of vitamin C in our blood and white blood cells actually reduces – this is when supplementation can be of benefit. Vitamin C helps to prevent the common cold and it has also been shown to reduce the duration of a cold by 8% in adults and 14% in children – resulting in fewer days off work and school. Information about how much vitamin C we should take varies hugely – some studies report benefit at as little as 200mg daily – whereas others suggest doses of 10,000mg daily. Taking a pragmatic approach I would suggest consuming between 500mg – 1,000mg daily for prevention (conveniently that’s the amount available in most supplements!). If you want to increase your dose, say perhaps you are surrounded by sick people or have fallen sick yourself, then 3,000mg – 5,000mg daily taken in divided doses throughout the day is likely to be beneficial.
Vitamin D – also known as the sunshine vitamin this nutrient has been the subject of lots of research of late. Low vitamin D has been associated with an increased risk of infection – including those of the upper respiratory tract – such as colds and ‘flu – which is why we tend to see more of these infections over winter when we have vastly reduced exposure to the sun. To be honest, Vitamin D makes my top 5 for more than its power against colds and ‘flu, it really is a nutrient that is proving to be essential for the prevention of many chronic diseases. If you can’t bare some skin to the midday sun for 10-15 minutes, then make sure you’re taking at least 1,000 IU daily from a supplement.
Zinc – this essential trace mineral is present in all body tissues and fluid and over 300 enzymes making it clearly integral for many physiological functions. On the immune front zinc is required for the normal development and function of our immune cells. Oral supplementation with zinc has shown mixed results for the treatment of colds; what has shown more benefit is the use of zinc in lozenges and nasal sprays. This is perhaps due to the ability to disrupt the virus where it begins – in the nasal and sinus passages. My take on this? Make sure zinc is in rich supply in your diet (or your multi-vitamin) for preventative purposes, and if you do fall ill, find a lozenge that contains zinc in it – aim for a daily dose of around 25mg elemental zinc.
If you do get sick remember that it is part of a normal immune response, what’s important is how efficiently and effectively our body deals with this attack. A typical cold should last no more than 3-4 days; during this time the most important thing to do is rest up. To help the immune system and to relieve some of the unpleasant effects of being sick I suggest finding a herbal medicine product that is suited to your specific symptom picture e.g. if you have a dry tickly cough the herb Marshmallow can be very soothing – if it’s a wet productive cough then Mullein  will help to clear this up.
Recurrent illness or chronic illness such as more than 2 colds per year, secondary bacterial infections ongoing coughs and constant exhaustion may be a sign of a fatigued under-functioning immune system and generally require more than the self-help listed in this article – so get yourself along to a natural health practitioner for more help.
Though the herbs and nutrients discussed in this article are GRAS it is recommended that pregnant women and people with existing serious health conditions discuss the use of them with their health care provider before commencing.
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