food nutrients that may help immune system covid-19

Foods & Nutrients that MAY provide some immune benefit and help with COVID-19

Let’s kick things off by being completely blunt and honest. Nobody knows if specific foods, nutrients or supplements will have a positive or negative impact on COVID-19, there have not been any specific tests as yet to look at this.

Whilst there may be some studies looking at the impact of certain nutrients on acute cases of COVID-19, this does not carry over very well with the general population and especially not for the phase of prevention, as any research currently being done using nutrient based therapies will relate to acute infections and those experiencing complications.

Therefore, everyone’s suggestions on the subject of foods, nutrients and supplements are either best guesses or simply a way to peddle supplement sales.

I feel it is important for practitioners like myself to remember the role that they play, which is largely trying to optimise one’s health and address chronic issues through nutrition and lifestyle modification, not fighting acute infections and pandemics.

Nothing that I mention here is replacement for the advice and guidance being provided by the government, the NHS and the World Health Organisation.

I also want to emphasise that where I mention supplements are also not a substitute for the foundational areas such as appropriate sleep, healthy balanced nutrition, stress management, movement and the minimisation or removal of substances like alcohol and cigarettes. This is the reason why so many of my newsletters prior to this one have been focused on management of anxiety, loneliness, structuring your day, adding in exercise during lock down and practical meal ideas to support you through lockdown as well.

Setting the scene – How might I get the COVID-19 virus?

Transmission of the virus seems to be via respiratory droplets and contaminated surfaces. Surfaces can remain a potential source of infection for days after the virus has been transmitted to the surface. The length of time that the virus is active depends significantly on the surface that it finds itself on and the temperature it is exposed to.

The human receptor for COVID-19 is mainly found in the lower lungs and is called human angiotensin-converting enzyme 2 (ACE-2). This is why the large majority of symptoms and complications relate to the lungs and of course difficulty in breathing.

We also have ACE-2 receptors in other areas such as the liver cells and bile duct cells, therefore we have potential risk for those with underlying conditions associating to this as well.

How do I know if I have COVID-19?

At the moment the clear message is to look out for the common symptoms of:

  • A new and persistent cough
  • Tightness in the chest
  • Fever/elevated temperature

It has also been reported recently that a loss of taste and smell may also be another symptom to look out for. Early studies show that the SARS-CoV-2 that causes COVID-19 can infect the nose and cause damage to the nerves.

We also know that many people with the virus can have either no symptoms at all or extremely mild symptoms, hence the importance of social distancing to slow the spread of the virus so not to overwhelm our healthcare system.

COVID-19 patients tend not to have digestive symptoms, however the anxiety that surrounds this situation is likely to exacerbate digestive symptoms in those with a history of IBS. If this is the case the mindfulness therapy and hypnotherapy are extremely useful tools to help combat this. If you would like support with this, I have two amazing practitioners I can introduce you to who are offering discounted sessions during this time.

The real gamechanger in terms of testing will be the introduction of an antibody test. This will allow us to look for who has had the virus at some stage but is now recovered. If we have had the virus in the past this means we are likely to have a much better immunity to it in the future, thus the risk of reinfection is very low. At this time of writing this, there are no reports on accurate antibody tests. There are some available, but the reliability and accuracy may be questionable, which is potentially riskier than no test at all.

With the antigen test (the test that tells you if you currently have it) there are only so many test kits and only so much capacity to perform the testing safely and process the tests as well. As a result, this means that at the current rate of testing, it would take around 20 years to antigen test the entire population of the UK, hence the focus is on critical patients and healthcare workers on the frontline.

So, are there any practical steps we can take from a nutrient, food and potentially supplement perspective that may help improve our resilience to the infection, helping to mitigate its impact on our health and improve outcomes?

Food, Nutrients and Supplements to Consider

Nutrients and herbs that will definitely help against COVID-19

None! Again, let me be very firm with this, there is no evidence on any level that can tell us for certain if a nutrient, food, herb or supplement will be useful specifically against COVID-19.

Some people will try and replicate the use of nutrients and herbs that show promise with normal colds, flus or other respiratory tract infections; however, this does not mean it will carry over to COVID-19, and potentially in some cases it may actually have a negative effect, so we must proceed with caution.

Nutrients and herbs that could have some potential in helping against COVID-19

Based upon what is known about the Coronavirus and how it infects us as well as what is known about viruses that are genetically similar to SARS-CoV-2, below are some of my loose guidelines with certain nutrients, herbs and foods.


This mineral is involved with more enzymatic reactions than all other trace minerals combined. It can help with respiration, bone health, liver health, processing alcohol (a significant reason not to be drinking much alcohol at the moment), protein digestion, production of red blood cells, antioxidants, thyroid function, cell mediated immunity and our defences to infection and much more.

Those at higher risk of deficiency include:

  • Elderly, vegetarians and vegans
  • Alcoholics or heavy alcohol drinkers, those with chronic illness, poor digestion, high stress etc

Some of the signs of low levels of zinc include the loss of a sense of taste and smell and impaired immune function. Sometimes white specks on nails can be an indication of zinc insufficiency as well.

Some of the best food sources of zinc include:

  • Oysters (exceptionally high)
  • Liver
  • Beef
  • Lamb
  • Venison
  • Spinach
  • Asparagus
  • Sea Vegetables
  • Broccoli
  • Sesame seeds
  • Pumpkin seeds

Supplementation of zinc is best done at low levels, but more frequent dosing rather than high dosages in one go. Also, you should be aware that excessive zinc supplementation can lead to copper insufficiency or if going far too high with zinc, it can lead to a metallic taste in the mouth, nausea, vomiting, abdominal cramps and other really pleasant things!

If in doubt, try to bolster your zinc levels through foods as this will provide a broad spectrum of nutrients and is less likely to cause any imbalances with your micronutrients, especially in the short term.

If supplementing then I would probably go for around 10-15mg a few times a day if acutely trying to increase zinc levels and would typically recommend adding a little copper (much lower dose, often just by pairing it with a multivitamin and mineral). Remember, not all zinc is created equally, some will absorb better than others into the body.

Zinc oxide for example being one of the most widely used in supplements yet is one of the most poorly absorbed. The dosages recommended here are not for long term use, and typically zinc can be obtained adequately from a well-balanced diet or with perhaps the inclusion of a decent quality multivitamin and mineral which will typically have 5-15mg for the daily total.

Okay, so why all the chat about zinc?

Zinc has the ability to reduce the effectiveness for viruses like COVID-19 to replicate, thus it may be able to help it cause less damage if it were to get in.


This is a natural pigment found in many fruits and vegetables. It can act as an antioxidant, anti-inflammatory and a mild antihistamine. As an antioxidant it can help to neutralise molecules that lead to more cellular damage and inflammation.

It has also been shown to have anti-viral effects and may help to promote the viral eradication or help to inactivate it and may also help with the uptake of zinc into the cell where it may provide some sort of protective effect.

Good food sources of quercetin include onions, citrus fruit, grapes, cherries and apples.

If one was to supplement, then I typically recommend around 500mg taken 2-4 x per day.


As well as copper offering balance to zinc, it has also been shown that coronavirus does not survive well on copper-based surfaces. This does not mean that it translates to copper supplementation to kill coronavirus though, although it may be toxic for it.

Foods that are rich in copper include:

  • Shellfish like Oysters
  • Organ Meats
  • Cacao
  • Potatoes
  • Spirulina
  • Shitake mushrooms
  • Sesame seeds

Copper is usually very well obtained from diet alone, however in the event that you are supplementing with zinc then around 1-3mg of copper may be a useful addition. Again, you will typically find this amount in a decent quality multivitamin and mineral.

Vitamin C

There has been some talk of IV vitamin C being used in studies in china and as part of the treatment strategy for some individuals in China. Bear in mind this will be using around 15-25 grams of vitamin C intravenously. This is acute care therapy and may not carry over to prevention or early stage treatment. Also, it has to be said this has not even been proven as an effective treatment or gone through rigorous testing.

My initial reaction was to increase vitamin C and recommend this because of vitamin C’s ability to help reduce the potential severity and duration of the common cold and flu virus.

For this reason, I am recommending vitamin C mostly from food and if someone has a little vitamin C kicking around then they can also dose some of that at the moment, but typically at lower levels like 250-500mg 3-4 times per day rather than dosing in the grams range regularly.

Good food sources of vitamin C include:

  • Oranges
  • Kiwi
  • Papaya
  • Berries
  • Brussels Sprouts
  • Pineapple
  • To be honest most colourful vegetables and fruits can be a good source of vitamin C

Vitamin D

Here is another one that initially I was keen to jump on top of myself. There is some reasonable evidence that vitamin D can help with the prevention of upper respiratory tract infections as well as general immune and anti-inflammatory support.

I have since backed off a little with supplemental vitamin D because there was a potential that Vitamin D, along with Vitamin A could increase the amount of ACE2 on our cells. Perhaps putting 1+1 together and coming up with 3, there is a thought process that this may in fact increase the risk of getting the infection. This all remains to be seen and is highly unlikely.

At the moment I am recommending a little vitamin D as a supplement with clients who I know are low in vitamin D (confirmed by blood testing), or generally a lower end dose of less than 1-3000iu per day. Ideally, I am recommending no vitamin D supplements and to get out in the sunshine when possible to top up vitamin D naturally as would be the best practice anyway.


Elderberry has been shown to be useful against genetically similar viruses to COVID-19, and for that reason the worldwide sales of Elderberry extract/syrups have gone through the roof.

The idea is that Elderberry can help to block the attachment of the virus to the ACE2 receptors, where it gets into our body and then replicates. Elderberry has been shown to be useful with other viruses, but again I stress, every virus is different.

Elderberry may be useful as a preventative, however if you have symptoms of an infection I would stop taking it on the risk that it could exacerbate the immune or inflammatory storm that follows once infected.


Allicin is the extract from garlic. I use a lot of garlic in practice as something to help deal with gastrointestinal microbiome imbalances.

Allicin does have some anti-viral capacity, but again it has not been tested against COVID-19 or other genetically similar viruses. Similar to zinc it may have some capability in reducing the replication of viruses, thus it may be useful.

Perhaps add a little more garlic to food if you wish, let’s face it you won’t be going on a date any time soon! Allicin comes out in garlic more when it has been crushed, chopped and left at room temperature for 5-10mins before eating.

Ashwagandha & Magnesium

Okay, here is a curveball recommendation. I use ashwagandha a lot with clients suffering with high levels of stress and anxiety, this is the only reason I have included this in this line up. In addition, I may combine it with a magnesium supplement if one is struggling with their sleep (500-1000mg of a mixed magnesium chelate), even after adopting good sleep hygiene habits.

You can also use Epsom salt baths with around 500grams and soaking for 15-20mins. The process of running and taking time out to have a bath as well as the impact of increased levels of magnesium in the blood via transdermal absorption I have found to be very useful as a broad recommendation to support sleep health.

Should you buy nutritional supplements to support you against COVID-19?

There are people out there for reasons beyond COVID-19 that require additional nutritional support, for example I am working with a dear friend who currently has cancer and purchasing the supplements to support his journey is exceptionally challenging at this time because of the panic buying of any supplement that may have any type of link to the immune system.

I had originally written this article almost 10 days ago, but intentionally delayed the release because of all the panic buying around supplements and the supplement scarcity. I get it, we all want to support ourselves as best as we can, but blindly buying supplements based upon limited knowledge of whether it will support you, especially if you are low risk and you are following all social distancing guidelines makes very little sense to me.

If you are an essential worker or potentially one of the vulnerable or elderly, then supplements may be something that could help to support you at this time. This should be viewed on an individual basis and the basics of wholefood nutrition, minimising or eliminating alcohol and cigarettes, optimising sleep, stress management and appropriate exercise is always the foundation before adding micronutrients and herbs into the equation.

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