Top 7 Immune Enhancing Foods and Nutrients to Boost your Immune System.
More than 200 different individual strains of viruses can cause flu and colds. Strains of these viruses are constantly changing, which is why it is important to always support our immune systems as much as we can naturally, even if we have been vaccinated against the flu. Furthermore, although the flu is not a life –threatening condition on its own, secondary infections such as throat and lung infections, can lead to more serious complications, especially among the elderly or anyone who suffers chronic health conditions including heart and lung disease which compromise immune function.
As COVID-19 (the Corona virus) spreads around the world, with new information making its' way out onto the media each day, we come to learn that this super bug is not only highly contagious and can potentially be lethal to the elderly suffering pre-existing conditions, but also to ones who are younger and are grossly overweight or obese.
Before looking at foods and nutrients to boost our immune system, it is important we recognise a few aspects of our health and lifestyle choices which may put us at a higher risk category, causing our immune system to not be firing at full capacity:
Multiple nutrient deficiencies, single nutrient deficiencies and imbalances among individual nutrients have all been shown to compromise the performance of the immune system and impair our resistance to infection.
It is important to be aware that even if we do over eat, over – indulge or over – feed ourselves or our children, our bodies can still be undernourished; Regular consumption of refined sugar (including soft drinks, energy drink and commercial fruit juice) refined carbohydrates (such as white flour based products including white bread, bakery goods, savory or sweet biscuits etc.) and junk food in general, will compromise our nutritional status as these nutrient – empty, calorie – dense foods over time ‘rob’ our bodies of its precious nutrient stores.
Some of the most common immune –related deficiencies we come across include the vitamins A, E, C, B6, B5, folic acid, iron, copper, zinc, Co Enzyme Q10 and the amino acid Lysine.
When our natural stress response or our Sympathetic Nervous system is hyper stimulated for long periods of time, it will compromise our natural immune competence and our ability to resist infection. Recent research has also associated prolonged stress with inflammation in the body, which is extremely demanding on our immune system to say the least.
Practicing mindfulness, yoga, meditation and pranayama (yogic breath – control exercises), can help calm our Sympathetic Nervous System (our ‘fight or flight’ response) and stimulate our Parasympathetic Nervous System, also known as our ‘rest and digest’ Nervous System. It can help bring more balance to the body and, in turn, take some pressure off the immune system.
When mum said you need to get some sleep to stay healthy, she knew what she was talking about.
There is now plenty of clinical evidence to show that people who regularly get 7 hours or more of good quality sleep per night are less likely to get sick. When sleep is compromised, the number of our immune – stimulating T cells decreases, while the number of inflammatory cytokines increases, which can potentially increase our chances of catching a cold, any type of flu or even potentially, COVID-19.
Furthermore, lack of good quality sleep can increase our cortisol levels, which can then compromise the health of not only our nervous system, but our immune system too.
As the temperatures drop and the days shorten, although the bed feels much cosier and may appear a hell of a lot more attractive than going out for a walk or a jog - this time of the year is actually one of the best times to get started on a regular exercise program.
Exercising in the colder weather will not only burn more calories (as the body utilises more energy warming us up when it’s cold rather than cooling us down when it’s hot, believe it or not!), but it will also stimulate our immune system and help us resist infections and flu.
But beware – over–exercising can have the exact opposite effect as it is quite taxing on the body and our immune system. So make sure you choose the types of exercise which make you feel energised once completed, not the types that make you feel like crawling back under the blankets for the rest of the day. So, make sure you enjoy at least 30 minutes to one hour of energising, immune - boosting exercise daily.
Vitamin C has been long known for its health and immune benefits. However, it seems to have become less ‘trendy’ amongst the health conscious in recent years as many have been trying different natural vitamins, herbs and other remedies.
As a clinical nutritionist, I still strongly believe, however, Vitamin C has an extremely important role in keeping us healthy and fighting off infections and should be the first ‘go – to’ nutrient when it comes to fighting any types of cold and flu.
The plasma concentrations of this important vitamin have been shown to drop during periods of infection and stress. Vitamin C cannot be stored in the body, and regular consumption of vitamin C rich foods as well as Vitamin C supplementation have been shown to improve the immune system’s antimicrobial and natural killer cell activity, support overall immune function and protect against free radical damage within the respiratory tract and in the inflammatory response. This would be my first nutrient of choice, especially given the strong association between COVID-19 and the respiratory system.
The best sources of Vitamin C include: uncooked tomatoes, strawberries, pineapple, sweet potato, potato, citrus fruit, broccoli, parsley, Brussel sprouts, blackcurrant and aloe Vera juice.
Bioflavonoids, sometimes referred to as ‘Vitamin P’, are magical super - nutrients which are widely available through the food we eat. They are found mostly in the same foods Vitamin C is found in, although they are in larger concentration in the fruit or vegetables’ skin as well as in the pith of any citrus fruit.
The Bioflavonoid group as a whole, helps strengthen the immune system by increasing the number and quality of white blood cells. The specific Bioflavonoid Quercetin has been shown to hold anti-viral properties as it actively binds to the virus proteins and interferes with viral RNA and protein synthesis.
The best sources of Bioflavonoids include all citrus fruit, nectarines, strawberries, capsicum,tropical fruits including mango and pawpaw, garlic, broccoli, Brussels sprouts,green tea.
This more than essential micro mineral has more than a full time job looking after the function of our immune system. It is a potent immuno-stimulant which nourishes our cells.
Zinc deficiencies have been associated with weakened immune response as low zinc levels have been shown to impair our immune cellular mediators including natural killer cell activity for instance.
Zinc supplementation combined with vitamin C has been shown to have a positive effect improving symptoms of colds and flu as well as shortening the duration of viral infections. Studies have concluded sucking on zinc lozenges rather than swallowing zinc tablets have the most favorable results.
The best sources of Zinc include pumpkin and sunflower seeds, ginger, seafood (especially oysters), eggs, ginger, beef, lamb, capsicum.
This wonderful flavour enhancer we use so often in cooking is more than a powerful antioxidant.
Garlic also contains over 100 sulfuric compounds which along with a compound called allicin, give it strong antibacterial, antibiotic and anti-inflammatory properties.
Tip: include garlic in cooking regularly to boost the immune system, but when fighting a cold or any infection, have raw crushed garlic mixed in salad dressings or with honey as some of the sulfuric compounds it contains are lost in the heating process. Garlic taken in capsule or tablet form is also a great way to support the immune system.
Another common and popular ingredient used frequently in cooking, baking and in herbal tea, ginger, is a super food you can’t ignore. Many are aware of the benefits ginger has on the tummy, as it helps relieve nausea, soothes a sore or bloated belly and helps improve constipation. But when it comes to our immune system fighting viruses and infections, ginger is an absolute super star. It acts as an anti-inflammatory and antioxidant plus it has also been demonstrated to have antiviral properties, as it stimulates respiratory cells to secrete antiviral protein. This makes ginger a perfect little fighter in the war against Corona virus.
One study suggests combining ginger with garlic and lime may help combat some types of drug – resistant bacteria.
Chilli is a rich source of Beta – Carotene which the body converts into Vitamin A. This essential nutrient is needed to help maintain healthy mucus membranes which protect the body against foreign invaders. Chilli also contains Capsaicin, a substance which acts as an anti-inflammatory and helps clear congestion.
Regular consumption of chilli has also been associated with an increase in antibodies.
The delicious Manuka honey contains up to four times the amount of nutrients we get in regular honey. It is quite significantly more expensive than regular honey, but when it comes to looking after your immune system – it’s money very well spent.
Manuka honey also contains significantly higher amounts of enzymes than those of regular honey, which create natural hydrogen peroxide that works as an antibacterial. The Unique Manuka Factor (UMF) rating you may find on Manuka honey jars, relates to its antibacterial strength. The higher the rating – the stronger the antibacterial properties. Lower UMF values of none to 10+ are beneficial to use as maintenance, while UMF of 20+ or higher are best used therapeutically, especially when treating any upper respiratory tract infections, sinus congestion and colds.
Tip: to treat a sore throat, have one teaspoon of UMF 20+ (or higher) Manuka honey every two hours. Manuka honey is best consumed at room temperature as many of its immune properties are lost when heated so avoid adding it to your tea.