There’s not much to love about winter: freezing weather, grey skies and wearing 10 layers every time you step out the door. But the worst part about winter has to be colds and flus. Experts say 3 times as many people have been diagnosed with the flu this season (2019), compared to the same time last year. Your best defence? The flu vaccine (if you’re an anti-vaxxer then please unfollow, I have no time for your uneducated opinions). Disclaimer: everyone is different, please consult your doctor for medical advice specific to your situation.But what about the gigantic and very wealthy world of supplements? Can they play a role in supporting your immune system? And can food help prevent you getting sick? – let’s find out!
Food – What Can Help to Boost Your Immunity?
FIBRE
80% of your immune system exists in your gut, which makes sense when you think about the fact that everything you put in to your body, passes through your digestive system. So, if you want to support your immune system – one of the best things you can do is look after your gut and gut microbiome!
When you eat foods rich in fibre (e.g. grains, veggies and fruit), the good bacteria in your gut breakdown the fibre. This process results in the production of short chain fatty acids (SCFAs). These SCFAs play a role in reducing inflammation, which helps to protect the lining of your gut from bugs that could potentially make you sick.
VERDICT: Include fibre in your diet to improve immune function and health
FERMENTED FOODS
Fermented food ingestion plays a similar role to fibre consumption, in that it supports your gut microbiota. Fermenting food increases its bacteria content. When ingested, this bacteria makes its way to your gut and positively influences the gut microbiome by increasing good bacteria numbers. Fermented foods include sauerkraut and kimchi, yoghurt, kefir, natto/miso and kombucha. Scientific evidence is lagging in this area, however, humans have been eating fermented foods for thousands of years and whilst they won’t cure all of your ailments, they may certainly work to improve your overall and gut health.
VERDICT: Not 100% backed by science, which is still lagging in this area, but a whole lot cheaper than most supplements and probably about as effective in improving immune function
FOODS RICH IN VITAMIN A
Found in: Leafy green vegetables, orange and yellow vegetables, oily fish, milk, eggs etc.
Vitamin A is crucial for maintaining mucus membranes and epithelium in your airways and digestive tract. Having healthy airways and a healthy digestive tract ensures that your body has the best physical defence to invading bugs.
VERDICT: Include vitamin A to improve your immune function and overall health
FOODS RICH IN ZINC
Found in: Meat, oysters, fish, pumpkin seeds, baked beans, fortified cereals, etc.
Ensuring you have an adequate intake of zinc can help to decrease your chances of catching a cold or flu. Taking a zinc supplement within 24 hours of getting sick can also decrease the symptoms you may experience.
VERDICT: Include zinc to improve your overall health and immune function and lessen symptoms of colds and flus
FOODS RICH IN VITAMIN C
Found in: Capsicum (sweet peppers), strawberries, kiwifruit, oranges, broccoli, etc.
Despite popular belief, vitamin C doesn’t actually work to prevent colds from occurring nor does it reduce their severity. Research has shown however, that vitamin C can slightly reduce the duration of a cold in healthy individuals.
VERDICT: Include foods rich in vitamin C for overall health and when sick with a cold to help shorten its duration.
Supplements – Yay or Nay?
PROBIOTICS
As we discussed earlier – the best way to support your immune system is to look after your gut and gut bacteria! Probiotics are live, good bacteria that can help to maintain a healthy gut by reducing the number of bad bacteria in our digestive system. Probiotic supplements are an easy way to increase the good bacteria in your gut, however, changes in the overall composition of the gut microbiota when taking probiotics are relatively small and usually only persist with regular use of the supplement. So much research is being conducted on the gut microbiota and we still have SO much to learn.
VERDICT:At this point in time, I would suggest that using a probiotic supplement is probably not a waste of time and money and could benefit more than just your immune system with regular use.
GINSENG
A meta-analysis of 5 randomised control trials (very high quality scientific study design), found that the use of North American ginseng extracts did NOT reduce the incidence or severity of colds (when compared to a placebo). However, 2 of those studies did show that 200mg of ginseng taken twice daily for 4 months DID shorten the duration of acute respiratory infections (including colds) in healthy adults.
VERDICT:Take twice daily for at least 4 months to see a reduction in the duration of colds. Will not prevent you getting sick.
GARLIC
Garlic is said to be useful for treating and preventing colds due to limited research which suggests it has antimicrobial properties. As with all supplements, some people choose to take garlic in capsule form due to its increased potency and convenience (plus it’s probably lot nicer to swallow a garlic capsule than eat a couple of cloves of garlic!). Research is limited, and the results are too mixed to be able to conclusively say that garlic can prevent, shorten or reduce the severity of colds. It can also result in rashes and of course, bad odour.
VERDICT: Not worth the money or stinky breath.
ECHINACEA
Echinacea is a herb native to the US. Its leaves, flowers and roots are used to make supplements. Echinacea contains compounds which are said to enhance the immune response. A large review of randomised control trials, found that Echinacea is ineffective in preventing and treating colds. Another review of scientific studies trailing the use of Echinacea for the treatment and prevention of respiratory infections and colds in children, found no beneficial effects of its use. Echinacea use has, however, been associated with an increased incidence of rashes.
VERDICT: Will not do anything except create expensive wee. Don’t waste your money.
THE VERDICT ON SUPPLEMENTS: They should supplement your diet, not make up the majority of your nutrient intake. Nutritional needs should be met primarily from foods. Consuming nutrient-dense foods means you are receiving essential vitamins and minerals, dietary fibre and other naturally occurring substances that work together to invoke positive health effects. Supplements merely provide you with some nutrients. In some cases, fortified foods and dietary supplements may be useful in providing one or more nutrients that otherwise may be consumed in less-than-recommended amounts and this should really be the only time that supplements are used. As with everything, always ensure you don’t exceed the recommended daily intake (RDI). Exceeding your requirements will result in excretion (so you’ll be wasting your money) and can also be dangerous!