Colds and Flu
Every year we encounter cold and flu season and I swear this year has been the year of that pesky cough, with the delightfulness of flu symptoms to go along with it!
The common cold is exactly that, common. It’s a viral infection we just have to let our body battle, leaving us with symptoms ranging from headaches, sneezing, coughing, sore throat, blocked or runny nose and a temperature.
Our immune system plays a vital role in helping protect and restore us during times of illness. It hosts a whole army whose purpose is to protect and fight against nasty pathogens.
Whilst preventative methods don’t always lead to success, it’s our best way to combat and reduce our likelihood of getting ill – after all, everyone gets ill at some point!
There’s a couple of ways which you can try to prevent catching a cold or flu by helping to keep your immune system up and running, or allow your body a shorter recovery time when it is struck with an illness. Some of these also play a role in reducing the duration of a viral infection so can also be used as a treatment.
Oranges offer a good dose of vitamin C
Vitamin C has properties which are antioxidant and has long been associated with being something to take when we have a cold, to help cure it.
A systematic review which looked at whether vitamin C reduced the incident, duration or severity of the common cold, as either a regular supplement, or just at the onset of the cold, found that when adults were taking regular supplements of vitamin C, the duration of their cold reduced by 8%, and in children by 14%. This roughly equates to half a day. The severity of colds was also reduced by regular vitamin C intake (Hemilä and Chalker, 2013).
However, it did not have an effect on the incidence of catching the common cold for the general population. For those who were partaking in intense physical exercise, including marathon runners and skiers, vitamin C intake halved the individual’s risk of catching the common cold.
When vitamin C was taken after the initial symptoms of the common cold, it was found that there was no reduction in the duration or severity of that cold (Hemilä and Chalker, 2013).
The authors of this systematic review concluded that there was limited justification for using vitamin C supplements for the general population. However, instead of jumping onto the supplements, why not just eat foods that are rich in vitamin C?
Vitamin C is a water soluble vitamin, which means that we cannot actually store any more than our body requires, so if you’re taking high dosage vitamin C supplements, a lot of what you may be taking will just be removed out of your body in your urine - that’s some expensive wee!
There are a vast number of foods which are rich in vitamins C including:
- Red peppers
- Brussel sprouts
One word of advice, vitamin C is heat sensitive so by putting foods which are rich in vitamin C into boiling water you can leach and destroy the nutrients. Try gently steaming or sautéing them, instead.
Zinc has also been associated for its role in preventing the common cold.
As above, a similar method was used to conduct a systematic review on the research provided online to see whether zinc reduced the incidence, severity and duration of the common cold.
It was concluded that no recommendation can be made due to the insufficient data being found to support the supplementation of prophylactic zinc.
Zinc lozenges or syrups reduce the average duration of the common cold in healthy people, when taken within 24 hours of the initial onset of the common cold symptoms. There is a variability of doses, formulation and duration of zinc and more research is needed.
If you are considering taking zinc, it is recommended by this review that you use 75mg/day from the zinc lozenges throughout the course of the cold (Singh and Das, 2013).
Warning though, be careful about taking zinc as it does have side effects including bad taste and nausea.
Elderberries (Sambucus) have traditionally been associated with being able to help protect and support our body against the common cold, and influenza (Tiralongo et al., 2016). It has been shown to have antimicrobial properties, being active against human pathogenic bacteria as well as influenza viruses (Krawitz et al., 2011).
A placebo controlled clinical trial found that those who were supplemented with the placebo had more episodes of colds, than those who had the elderberry after a flight. Those with the placebo had significantly longer duration of cold episode days, with significantly higher scored level of symptoms (Tiralongo et al., 2016).
Echinacea purpurea has been used in both North America and Europe to help reduce the duration and severity of the common cold.
It has been suggested that its extracts do have immunomodulatory activities - this means that it should enhance or suppress immune responses in accordance to the function required, and has been suggested to help upper respiratory infections (Barrett, 2003).
A systematic review looking at the effect cchinacea has on the common cold found that there was no association with the prevention of the common cold. However, it may help reduce the prevalence of the colds (Karsch-Völk et al., 2015). Other research into the area, has indicated that using echinacea can reduce the severity, with some studies also finding a significant reduction in duration, however other studies have found no reductions (Nahas, 2011).
There is an important compound found within garlic (Allium sativum) called Allicin, which is activated when we chop or crush garlic (Bayan et al., 2014).
Garlic has been associated with a whole other range of benefits including having anticancer and cardiovascular benefits (Nahas, 2011). When extracted it has been seen these compounds have beneficial effects against microbial infections, as well as being anti-inflammatory (Arreola et al., 2015).
It has been suggested that garlic may be able to maintain the homeostasis of the immune system, helping to regulate its functions.
Allicin has also been found to have antimicrobial activity helping to control infection (Arreola et al., 2015). It has been found that garlic is effective against multiple bacterias, demonstrating antimicrobial properties. It has also been shown to potentially being antiviral, with a study finding that the occurrence of the common cold in participants was reduced by 64% in those taking allicin, compared to those on a placebo, but more research is needed to confirm this research (Bayan et al., 2014. And Nahas, 2011).
Green tea contains a compound called epigallocatechin-3-gallate (EGCG), which is known for its antibacterial effects, and it has also been found to have antiviral properties (Reygaert, 2014).
Influenza A and B viruses are some of the major causes of respiratory disease in humans. EGCG has been shown to cause the influenza virus to become inhibited to ineffective, with other research finding that a continuous consumption over 5 months has a preventative effect on clinically defined influenza (Steinmann et al., 2013).
It has been shown that our gut health has an impact on our immune system. The microbiome which are found within our intestine, help to modulate the immune cells, and how well our body responds to infection.
It has been shown that when the microbial balance in the intestine is out of sync, it can trigger immune disorders, disabling our body from modulating or preventing inflammatory disease. We have several blogs which are based on gut health - one of these articles looks at fermented foods and how they impact our gut health and overall health, which can be read here.
It has also been found that probiotics reduced the number of participants who experienced upper respiratory tract infections, the duration and school absences, than those on placebos (Hao et al., 2015).
Sleep and Stress
Sleep has been advised for a while as a method to both prevent and treat illness. The European Prospective Investigation into Cancer and Nutrition (EPIC) study, found that when subjects had a sleep duration of less than 6 hours, it was seen as risky behaviour for the development of chronic diseases (Ruesten et al., 2012).
There has been a link between both acute and chronic inflammation and sleep - disrupted and lost sleep - with studies finding that when healthy human volunteers were restricted or deprived of sleep, there were changes within their circulation of pro-inflammatory cytokines, as well as affecting their anti-inflammatory cytokins, innate immunity and inflammatory signaling pathways (Opp and Krueger, 2016).
Those who work within shifts also show an increased risk of viral infection, due to potentially the compromise of both their innate immune response and also their immune acquired response (Oliveira de Almedia and Malheiro, 2016).
Even in regards to the common cold, when healthy men and women were sleeping for less than 5 hours, or sleeping between 5-6 hours, they were at greater risk of catching the cold, than those who were sleeping at least 7 hours (Prather et al., 2015). This indicates that sleep itself is an important part of our overall immunity, and in the homeostasis of the neuro-immuno-endocrine system (nervous, immune and endocrine system) (Aguirre, 2016).
Fatigue is a state of energy depletion and has been linked to a wide range of diseases and ill health. It has been seen that when individuals have poor health, and it has been associated with being fatigued, it impacts sleep and inflammation (Åkerstedt et al., 2014). A study which looked at individuals over 42 days, found that day to day fatigue resulted in poor sleep quality and duration, leading to a higher stress response, and increased occurrence of a cold or fever, leading to poor subjective health (Åkerstedt et al., 2014).
Stress can be beneficial in short bursts but when stress is encountered for prolonged periods of time, it leads to the continuous release of hormones called cortisol.
Cortisol is a steroid hormone, which suppresses the immune system (Olnes et al., 2016). In periods of time where there is chronic stress, it causes a continuing activation of the sympathetic nervous system, which causes the immune system in turn to have continuous levels of pro-inflammatory cytokines. This in turn may lead to major depressive disorder (Won and Kim, 2016).
It has been shown that immune function is depressed by chronic stress but acute stress may enable the enhancement of immune function, so short-term peaks in cortisol do not cause inhibition of the immune response (Koelsch et al., 2016).
It is important during the fast-paced lifestyle that we live, that you take time out for yourself during the day, do something that you like and that relaxes you, whether that be reading a good book, mediation, yoga, practicing mindfulness, going to the gym, cooking, anything! Put down your phone or computer for a moment and enjoy everything that is surrounding you, listen to your body and see how it is feeling. If you need a bath and an early night, try and have one.
Making sure that you wash your hands when necessary is one way to help reduce your risk of transferring and catching the illness. If you are ill, you’ll probably know the campaign phrase “Catch it. Bin it. Kill it” (Department of Health, 2013).
This campaign was aiming to reduce the transferal of the flu, aiming for people to sneeze or cough into tissues, instead of their hand, preventing the virus from spreading from their hand onto the surroundings (hand rails, door handles etc.).
When there is a flu spreading, hygiene is one of the main ways in which we can prevent it. It has been indicated that respiratory infections are reduced when groups practice good hand and respiratory hygiene (Department of Health, 2013). Prevention of respiratory and intestinal viral infections are best prevented through hygiene (Bloomfield et al., 2016).
Although it is important to practice good hygiene, this does not mean that we should live within a sterile environment and be too excessive. There is a hypothesis known as the hygiene hypothesis outlined by Dr David Strachan, whereby he proposed that due to the lower incidence of infection through early childhood, it has caused the rise in diseases (Bloomfield et al., 2016).
By being aware of our hygiene and having a good hygiene practice, means that in many cases we would be able to reduce our antibiotic usage, and therefore reduce the risk of antibiotic resistance, which is discussed below.
It has been argued that it is important that we are exposed to microbes which were present when the human immune system was evolving. These microbes are found within both our indoor and outdoor environment. Having a diversity of microbes is important as it allows the immune system to balance and prevent overreactions (this causes allergies) (Bloomfield et al., 2016).
Therefore, it is important that when we are kids we go outside, explore and play, and pick up some microbes to help with our immune system and our allergen response, but this does not mean we should practice poor hygiene.
When women are pregnant, the first milk that is produced is known as colostrum which is a yellowish colour. This form of milk is full of antibodies and immunoglobulins and helps protect the infant and give them their first defence when they come into contact with bacteria and viruses. So, it is beneficial to feed this to your child due to the antibodies and immunoglobulins (even if you do not continue).
In essence, the better shape we are in, the easier it should be for our fight back against disease and illness.
It has been noted that physical activity helps to prevent many chronic diseases including obesity, type 2 diabetes, depression, and coronary heart diseases, to mention a few. Further, those who are inactive are causing detrimental effects to their health, as well as the functioning of their organs and suppressing their immune system (Booth et al., 2012).
It has been found that regularly doing moderate exercise helps to reduce our risk of catching an infection, in comparison to those who lead a sedentary lifestyle (Booth et al., 2012).
However, when we do prolonged, intense, strenuous exercise, such as marathon running, it actually causes a gap of immunodepression whilst the body is recovering from the activity. This is when our immune response is down, due to the recovery process from the stress of exercising, causing us to be more susceptible to illness (Peake et al., 2016. And Booth et al., 2012). If we do not allow our body to recover after continuous sessions of intense physical exercise, this can also increase our risk of susceptibility to illness (Peake et al., 2016).
It has been found that periods of intense physical exercise lasting over a week may cause longer immune dysfunction (Booth et al., 2012).
It’s highly unlikely that you’ll be unable to avoid getting ill for your whole life, it happens to all of us. So, here’s a couple of tips for when you are ill, to try and help you along the road to recovery!
Warm Water with Lemon and Honey
I don’t know if this is the same for you, but whenever I was ill when I was younger, my mum used to make me warm water with lemon and honey.I say warm water because boiling water can actually cause both honey and lemons’ nutrients to be destroyed, rendering them slightly useless.
Lemons are rich in vitamin C but as we have seen above, unless you are doing intense physical exercise this probably doesn’t have any effect in reducing your duration or severity of your cold, but hey, I will still have one even now because I feel like it does have a soothing effect, especially with the honey added to it.
So, what about honey? Well doctors now actually recommend we use home remedies to treat coughs and tickly throats instead of specific medication (which I discuss why they do below, under cough medicines).
Honey has actually been proven to have an effect on reducing irritating coughs. It has been found that honey may help to reduce mucus secretion and also coughs in children, and may have antimicrobial effects (Goldman, 2014). It also has been shown to help improve sleep quality for both the child with the respiratory infection and the parents (result!) (Cohen et al., 2012).
Honey should not be given to children under the age of 1, due to the risk of infant botulism (NHS, 2015).Ginger
Fresh ginger can be added to water, smoothies and used in cooking as a healing food
The ginger family has been used for medicinal purposes for centuries, as part of a healing process.
It has been used in Chinese medicine for treating vomiting, weak pulse, cough and sputum production. It has also been found to be antibacterial and antifungal (Azizi et al., 2015).
Fresh ginger has been shown to be effective in having antiviral activity against human respiratory viruses, helping to inhibit the virus from developing (Chang et al., 2013).
The compounds in ginger have also been found to be therapeutic in helping to induce relaxation of our airways (Townsend et al., 2013). I sometimes like to add a little bit of grated ginger or sliced ginger into my warm water, lemon and honey.Facial Steamers and Humidifier
Steaming helps to loosen congestion. All you need to do is place your head over a bowl filled with boiling water and place a towel over your head, then breath in though your nose and exhale through your mouth. Just be careful not to burn yourself with the steam though.
You can also add essential oils like eucalyptus and peppermint which both have antiviral, anti-inflammatory and antibacterial effects, helping to sooth the respiratory infection.
You can also, if you have a diffuser which you can use these with, add some of these oils so that your room fills with the smell, which can really help to decongest. A humidifier may also help to reduce dry throats for when you sleep.Gargle, Gargle, Gargle
The NHS recommend as a treatment for sore throats, to gargle a homemade mouthwash of warm, salty water (NHS, 2016). There is limited research on how effective gargling is overall though (Allan and Arroll, 2014).
Taking time to rest, when you're under the weather, can be hugely beneficial in fighting colds and flu
Sleep has been long advised as a treatment for times of illness to allow our body to recover. Even the founder of medicine, Hippocrates made reference to the role of sleep over 2,400 years ago, and how it has restorative properties in times of sickness (Opp and Krueger, 2015).
When you’re fighting something, it’s important to make sure that your rest up. If that means skipping your usual gym session you should! It’s worth allowing your body to focus on fighting the infection and hopefully giving you a quicker recovery time.
If you are sick and work out, which increases your heart rates, makes you sweat, and increases your breathing, it stresses the body and can be too much for your body and your immune system to handle when you are ill, even potentially making you feel even worse. This doesn’t mean you can’t move at all, just do lighter-based physical activities like walking - listen to how your body is feeling.Cough Medicines
Although these are obviously sold to help soothe and reduce coughs, through suppressing the cough itself or stopping phlegm being coughed up, they are not recommended by the NHS. This is due to little evidence being found supporting their role in helping these symptoms as any more effective than remedies which you can make at home. Also cough medicines are not suitable for everyone to use (NHS, 2015).Medication
It may be that you need to take some medication to bring down the fever, or reduce aches and pains. There is also medication available which is targeted specifically at flu and cold symptoms. Always read the guidance of usage when taking medication, and whether it has any interactions with any other medication you may be taking.Antibiotics
We are given antibiotics when we have picked up harmful pathogens. Antibiotics work by killing or preventing bacteria from reproducing.
Within our gut this also kills all the good bacteria which help to keep us healthy and our immune system functioning.
It is really important that we do not take antibiotics for when we have viral infections and this includes most colds, flu, most coughs, and sore throats, as the antibiotics will do nothing for fighting the infections or be of any help.
However, if you are given antibiotics by your doctor, it is really really really (yes that many!) important that you take the recommended amount per day AND also to finish the pack. If you don’t, you potentially haven’t killed off all the bacteria which caused you to become ill (even if you feel better), and this leads to more antibiotic resistant bacteria.
Also, you can become ill again and those antibiotics may not be as effective the second time around, leading to a whole host of other issues for your body to try and combat.
It’s also important to stay hydrated whilst you are ill, well it’s important to stay hydrated full stop!
You can have warm soups and warm drinks to help ease congestion and keep your fluid levels up, this should help to ease any headaches as well. Vitamin D also helps to strengthen our immune system, you can read more about vitamin D here.
A healthy balanced diet and physical activity are always important as well in maintaining optimal health. If your nose is sore from blowing it, you could always rub a bit of coconut oil to the area to help sooth it as well.
Even if your immune system is strong and you’re physically active and well, it doesn’t mean that you will be immune to getting ill. If you ever get ill its always important to rest and take care of yourself, listen to your body and let it recover before you put it under more stress. If you put it under more stress it may lead to a longer road to recovery.
A lot of cases of coughs clear up on their own within three weeks, however if you do struggle getting rid of yours, it is worth seeing your GP so that you can see if there is another cause.
You may even have an old family remedy which your parents used on you, and that you still do today. If this is the case it would be great to hear from you!
Daisy, MSc PGDip ANutr, is a Registered Associate Nutritionist with a Master's Degree in Public Health Nutrition, and a Post Graduate Diploma in Eating Disorders and Clinical Nutrition, both of which are Association for Nutrition (AFN) accredited. She, also, has a BSc degree in Psychology and Cognitive Neuroscience; and has completed an AFN accredited Diet Specialist Nutrition course.
Daisy has worked for an NHS funded project, the Diabetes Prevention Programme; and shadowed a nutritionist in Harley Street.
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