11 tips for preventing and overcoming a cold or flu

As the cold and flu season is now here, I decided to write an article about what you can do to prevent and overcome a cold or flu naturally.

The key for staying healthy or becoming healthy again is to strengthen our immune system. So all the approaches I will write about here do exactly this, and they are all backed up by scientific articles, as you will see.

Did you know that those unpleasant cold/flu symptoms are actually part of our body’s healing process? The immune system is fighting to get rid of those viruses. For example, coughing is an annoying symptom, but it is a way to clear our breathing airways of thick mucus which carry germs. Fever is also very important. Did you know that fever has evolved to increase our survival in response to infections? [1, 2] The activity of certain cells of our immune system (a particular kind of lymphocyte) is enhanced by fever (in this specific study, 39.5°C) [3]. In fact, in this study [1], the authors say ” it is probable that the use of antipyretic/anti-inflammatory/analgesic drugs, when they lead to suppression of fever, results in increased morbidity and mortality during most infections“. I hope this has altered your view of fever and will let you relax if you have a little high temperature due to a cold! Although fever is uncomfortable, it is an important and effective response of our immune system! However, if the fever rises very high and very fast, do seek medical attention. For infants of less than 3 months, do seek medical attention if they have any fever.

Note: Be aware that fever due to an infection is very different from fever due to a heat stroke (caused by surrounding heat and inadequate fluid intake) – in this case you do need to decrease the temperature as soon as possible and seek medical attention immediately. But in the current article, I’m talking about a completely different situation – fever caused by infections.

 

Now, there are things that you can do to accelerate and support your recovery, and because of that, the fever will go down anyway – because we are getting healed, and not because we took a drug to mask this important symptom that is there to help us, as I said above. I will talk below about these methods.

I know that many people think that they have to take pills in order to overcome a cold or otherwise it will last for ages. I belonged to this group of people some years ago. However, this is totally not true. You can follow instead other approaches that will naturally support your body to heal. And, in my experience (with me and others), these approaches are more effective and act faster. For example, a few years ago, my sister-in-law told me she had this cold and cough already for many weeks and it just seemed to not go away. I recommended her some of the approaches below and gave her my essential oils. Within 1 day she was feeling much better. Within 2-3 days she was healthy again (note that she seemed to not get better for weeks and with these natural approaches she recovered in only 2 days).

So, what are these approaches that you can follow to strengthen your immune system and prevent or overcome a cold or flu?

 

1. Eat plenty of raw vegetables and fruits

If you are sick or are trying to prevent getting sick, it is really important to eat more fruits and raw vegetables in order to increase the intake of vitamins and other important micronutrients.

In a previous post, I wrote that a high intake of vegetables and fruits is associated with lower rates of many chronic conditions. Not surprisingly, they can also prevent and help overcoming common colds and the flu [4]. Why is that? Well, vegetables and fruits have many important phytochemicals that help our immune system fight invaders. For example, they contain antioxidants that help protecting our cells from oxidative stress and lower the risk of diseases [4, 5]. But an important note here: antioxidant supplements do not work as good as antioxidants obtained directly from whole foods [3]. Also, in order to fully profit from the antioxidant content of fruits and vegetables, you have to eat them raw, as cooking destroys many of them.

A good way to increase your raw vegetable intake is to make smoothies and juices. Note that a smoothie is when you put veggies and fruits with water in your blender and a vegetable juice is when you separate the juice of the vegetable itself from the fiber. As I said before, I really think a vegetable juice is a very powerful supplement due to the amount of vegetables (and thus, micronutrients) that we are able to consume at once. If you have the possibility, I recommend you invest in one of those machines (a slow juicer). Also, try to include vegetables of different colors in your juice: for example beetroot, carrot, fennel, purple cabbage, cucumber, fresh ginger, fresh turmeric, lemon, dark green leaves such as spinach, etc. This is important as vegetables of different colors will have different phytochemicals. So basically, aim to “eat the rainbow” :). A note here: I do not recommend juicing fruits, as when the fructose present in fruits is separated from the fiber, it is absorbed very fast causing a blood sugar (and insulin) peak. So, juices – only for vegetables.

Now, fiber is also super important and this is why I look at vegetable juices as supplements rather than “common foods”. On the other hand, if you can, please do a smoothie as well or/and eat a big salad with lots of veggies (of different colors) to get your daily fiber intake and another boost of vitamins. And in the smoothies you can put some fruits, otherwise it is a bit difficult to drink it 🙂

You have probably heard that eating citrus fruits is important due to their high vitamin C content. While you shouldn’t focus on only one single vitamin, but on a whole range that is provided in different fruits and vegetables, it is indeed true that fruits rich in vitamin C support our immune system. For example, kiwifruit has been shown to support immune function and reduce the incidence and severity of cold or flu-like illness in older adults and children [5]. Beyond vitamin C, they are good sources of vitamin E (another antioxidant), vitamin K, folate, carotenoids, potassium, fibre, and phytochemicals [6]. Researchers found that kiwifruit consumption reduces the severity and duration of certain upper respiratory tract infection symptoms, such as head congestion and sore throat [7].

In  pregnant women, it was also shown that the ones who consumed plenty of fruits and vegetables had a reduced risk of getting an upper respiratory tract infection, as they strengthened their immune system [8]. The women in this study were consuming an average of 9 servings of fruits and vegetables per day (5 of fruits and 4 of vegetables). Do you still think you eat enough fruits and veggies? 🙂

I also recommend you include raw garlic in your meals / smoothies as well as fresh ginger given that they both have been proven to be “natural immune boosters” [9] (the author’s own words in this study, by the way). Garlic has antiviral and antibiotic properties [10], and has been shown to prevent and help in a faster recovery from colds [11] (just mind the smell afterwards 🙂 ). Fresh ginger contains phytonutrients with antiviral [12], anti-inflammatory and antioxidant properties [13]. For your information, in this study [9], they also mention that ginger and garlic (as well as other herbs and spices like green tea, Echinacea, black cumin, licorice, astragalus and St. John’s wort) have “anti-inflammatory activities that are helpful against cancer“.

Now, I’m not saying you shouldn’t eat a soup while you are sick. Actually, you should because this will keep you warm and also because some micronutrients in vegetables are even more absorbable when cooked (just keep in mind that many antioxidants will be basically gone, so again, don’t forget your daily raw vegetable intake).

When possible, try to buy organic fruits and vegetables as they contain more antioxidants and also less pesticides and herbicides than conventionally grown ones [54].

 

2. Cut on junk food

In this “food” group, I don’t mean only the obvious fast-foods, but actually all foods which contain sugar (stated on the food label as 1 of more than its 50 names), refined flours, trans-fats (partially hydrogenated oils), artificial additives etc.. This is really really important. If you continue drinking soda, eating sweets (or white bread for that matter) or other packaged foods that contain these ingredients, it will be difficult for your body to recover fast. Opt instead for real foods: plenty of vegetables, fruits, healthy fats (nuts, olive oil) and good sources of protein (like legumes, for example).

 

3. Drink plenty of water

Staying hydrated is key to keep a healthy immune system and therefore, to prevent and overcome  a cold or flu. If you have a fever, you will need to drink even more fluids. You can drink part of these fluids as herbal teas.

 

4. Medicinal herbs

Fresh ginger and lemon peel tea are great for preventing and treating a cold or flu. As I said above, ginger has powerful anti-viral  anti-inflammatory and antioxidant properties [12, 13]. But please use fresh ginger, as the dried one doesn’t have anymore the same benefits. The lemon peel has also important health benefits such as anti-inflammatory and anti-cancer activity [14].

Elderberries have been traditionally used for treating colds and the flu and their anti-viral benefits have now been confirmed by scientific studies [15]. They contain quercetin, which has also anti-histamine and anti-inflammatory effects [16] – so it might help in allergies as well. However, many elderberry syrups available are packed with sugar, which is counteracting its healthy benefits. So I recommend you either try to find one without sugar or artificial sweeteners, or you make your own if you have an elder tree and have the possibility to collect the berries. However, these berries are poisonous when eaten raw, so you will have to cook them first. In the elderberry season, I will post a recipe for doing your own elderberry syrup for the whole year. You can also make a elder flower tea.

Echinacea is an antiviral and antibacterial herb that can effectively treat respiratory-tract infections, as shown in a double-blind randomized controlled trial [17]. Echinacea is available as an extract or tablet form.

Propolis is a natural resinous mixture produced by honey bees and used in the construction and repair of their hives. Propolis has shown anti-bacterial, anti-inflammatory effects, anti-fungal and anti-influenza virus activity [18-20] and it has been used to treat upper respiratory tract infections, common cold, flu-like symptoms, wound healing, treatment of burns and some skin diseases [21]. Propolis is available in health food stores in capsules or extracts.

 

5. Essential oils

Essential oils are probably among the most powerful remedies out there. It’s impressive that not everyone knows about them given that there are literally thousands of scientific studies proving their health benefits. I will write more about them in future articles, but for now, know that they have many properties, including antioxidant, anti-microbial, anti-inflammatory and anti-cancer activity [22, 23].

Essential oils are extremely powerful, as they are highly concentrated, and thus, should be used carefully. You will typically need only 1-2 drops at a time and mixed with other carrier oil.

Note: scientific data on essential oil safety when taken internally is still very limited, so if you decide to take them internally, be cautious. Likewise, data on essential oil use during pregnancy is very limited. In general, it is recommended not to use them during the first trimester of pregnancy, but there are certain oils that seem to be safe in the second and third trimesters (and also during labor – get informed with your midwife about that).

So, for fighting a cold or flu, I normally use the following essential oils:

  •         lavender
  •         eucalyptus
  •         peppermint
  •         cajeput

I actually use an oil that contains a mixture of eucalyptus, peppermint and cajeput essential oils. But if you just find one of them, it’s ok as any of them will be helpful. The ways you can use them:

– mix 1-2 drops of of one of these essential oils (normally, I use lavender) in 1 teaspoon of a carrier oil (olive or coconut oil, for example) and put it directly on the chest. Try to do this every 2 hours. You will feel that your airways will clear up faster and your breath will become easier.

– you can open the bottle of the eucalyptus/peppermint/cajeput essential oil and inhale the smell. You will see that it will help to clear up your nose.

– alternatively, you can add 4 drops of one of these oils (or the mixture) to a bowl of hot water and inhale the steam.

– you can diffuse one of these essential oils in your home using an essential oil diffuser. Fill the diffuser with water and then add 10-30 drops of the essential oil of your choice.

A randomized, placebo-controlled double-blind crossover study also showed that peppermint essential oil can effectively relieve headaches [24]. A solution of 10% peppermint oil was spread on the forehead and temples and this was again repeated after 15 and 30 minutes. Compared to the placebo, the application of 10% peppermint oil reduced the headache in the participants already after 15 minutes! Quite interestingly, they found no difference between the efficacy of 1000mg of acetaminophen (paracetamol) and the 10% peppermint oil. Pretty remarkable, don’t you think? Maybe next time you have a headache you give this essential oil a try? 😉

There are of course other oils that you can use. For example, oregano essential oil also has potent anti-viral, anti-fungal and anti-bacterial effects (even against multi-drug resistant bacteria) [25, 26]. To use this oil you can put a few drops in a pot with hot water and inhale the steam.

Try to buy always organic essential oils and make sure that they have a high quality (only by from a reputable brand).

 

6. Gargling

Gargling seems to be one of the best approaches to soothe, and also to prevent, a sore throat [27]. A randomized trial showed that people who gargle had less upper respiratory tract infections than people who didn’t and even in people who gargled and did have such infections, they had more attenuated symptoms [28]. Also, in a study in 19,595 children (2-6 years old), it was observed that children who gargled had less fever episodes than children who didn’t, especially the group of children who gargled with green tea or filtered (spring) water [29].

Gargling can be done with water, water with a bit salt or baking soda, or with green tea.

 

7. Supplements

First of all, supplements DO NOT replace healthy food. You still have to eat healthy. So, besides healthy eating, there are certain supplements that can also support our immune system:

– vitamin C: this is probably the most obvious to you. Indeed, some studies have shown that vitamin C supplementation can reduce the duration and severity of colds, although it is still debatable whether it also prevents colds [30]. In these studies, they considered 1 to 2g of vitamin C per day. However, in another study, it was shown that megadoses of vitamin C (hourly doses of 1g for the first 6 hours and then 3 times daily) reduced 85% of the symptoms of flu and cold when compared to the control group [31]. Vitamin C can also help relieving asthma caused by respiratory infections [32].

– vitamin D3: it can help strengthen our immune system and reduce the incidence of influenza [33].  The problem is that the majority of us are deficient in this vitamin, especially during winter months (but, for many of us, also during summer). So make sure you take a good quality vitamin D3 supplement and, if you are not sick, 2000 IU/day. If you are sick, you might want to increase this dose to accelerate recovery, together with a vitamin K2 supplement. For more information on the vitamin D topic, see our previous articles: this one, this one and this one.

– selenium: its key role for our immune system has now been recognized [34, 35]. For example, it can trigger apoptosis (cell death) of leukemia cancer stem cells [36] and help in the treatment of Hashimoto’s thyroiditis [37]. So you can see how important adequate levels of this trace mineral are.  Beyond many other functions, it can help fighting viral and bacterial infections [38]. You can eat 3 Brazil nuts per day. This will provide you more than the RDA – no need for a pill.

– zinc: it can also support the immune function and reduce the duration and severity of colds [39-42]. However, zinc supplements might have some adverse effects, and therefore, I recommend you increase instead the consumption of foods rich in zinc, such as chickpeas, lentils, beans, pumpkin seeds, sesame seeds, cashews, mushrooms and spinach.

– probiotics and prebiotics:  certain probiotic strains can have systemic immunity-enhancing effects by boosting the number of white cells that target potential invaders [43]. Interestingly, in this study, they also found a boost in the ability of natural killer cells to kill cancer cells [43]. A randomised, double-blind and placebo-controlled study also showed that people who take certain probiotic strains, particularly Lactobacilli, have significantly fewer colds, sick days and cold symptoms [44]. Another study in children showed that probiotic supplements, with specific strains of Lactobacillus acidophilus, taken during 6 months, reduced the incidence of fever, nasal congestion, cough and antibiotic prescription [45]. A Cochrane Database review also showed fewer upper respiratory tract  infections in people who consumed probiotics compared with people who didn’t [46]. Prebiotics are specific types of fiber found in plant-based foods (legumes, vegetables and fruits) that feed and support our good gut bacteria and have actually been said to even outweigh the benefit of probiotics [47]. Part of the reason is that some probiotic pills might not have what they state on the label [48], might not be active anymore, or might be destroyed in our body. This is why I recommend you consume rather plant-based probiotic foods such as sauerkraut or other fermented vegetables, which you can make yourself or buy. If you buy them, make sure they are not pasteurized and do not contain vinegar, otherwise they will have no probiotic value. They should contain only cabbage (or another vegetable), salt, water and maybe some herbs, and it should specifically state that it is not pasteurized. You can find these type of products in organic food stores. In addition, raw fruits and vegetables, beyond all the properties mentioned in section 1, might also have both pro- and prebiotic value. They are covered by lactic acid bacteria, some of which are the same type used as probiotics [49]. How interesting is that?

 

8. Physical activity

Keeping ourselves actives can also help us preventing cold or flu. A study in 1002 adults showed that the ones that were doing aerobic exercise regularly had significantly fewer, and also less severe, upper-respiratory tract infections than sedentary people [50]. However, this is for prevention – if you are sick, it is important you take some rest.

 

9. Reduce your stress levels

As you have probably realized, it’s more likely that you get sick during or after periods of high stress. I normally say that it’s our body shouting at us “please stop!!”. Indeed, the role of stress in inducing or regulating inflammatory response is well documented [51]. Also, when you are stressed and with little time for yourself, it is more likely that you will not do all the other steps outlined in this article – so basically, taking care of yourself. So, try to give yourself some time to relax and enjoy your day, even if this is only 10 min of meditation, while you mindfully prepare your healthy food that you know will nourish you, doing yoga, dancing, talking to a good friend, walking, etc.

 

10. Take a rest, sleep and stay warm

Try to sleep enough because it is known that chronic sleep deprivation affects the immune system and leads to inflammation [53].

Also, if you are sick, take a rest, sleep and stay warm. This might sound obvious to you, but it is really important for the healing process. This will help our body to focus its energy in fighting those viruses. It is also important to sleep enough as while we sleep our body is recovering and healing [52, 53]. However, it does seem that sleep is altered during infection processes, especially during fever, and this has been argued to be important for recovery [53]. As I mentioned above, fever is very important because immune responses are potentiated at elevated body temperature, and because high temperatures are not ideal for replication of pathogens.

 

11. Get enough fresh air

Being always inside is not optimal because 1) the virus stays in this closed environment (try to open the window sometimes) and 2) the dried air due to the heating system is not optimal for our airways. So get out and enjoy the fresh air, even if it is a little cold, it will be good for you 🙂

I hope these tips are helpful for you and your family! Let me know, I would love to hear from you 🙂

 

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