Home » Supplements to Boost Your Immune System

Supplements to Boost Your Immune System

Should I be taking supplements?

This is a common inquiry we are currently receiving at MERN Chiropractic and although it is a simple question, in reality, it is a much more tricky question to answer.

This blog is a longer read than my usual posts – I try to keep them short and to the point.  However, as supplementation is a vast, complex subject, this is the short-to-the-point version to shed some light on the subject without cheating you all of vital information. It hopefully caters for both those who just want to know the bare facts and can skim through the text, and others who want to read deeper.

Please note that this Blog is intended for general advice and guidance only. Any readers with medical conditions or specific questions should seek further medical advice from their GP or Health Provider.

There is no doubt that we as individuals should take responsibility for our own health as much as we can, therefore supplements which may help support immune function can be a useful way of helping to protect our health. Yet, many of us pop them like sweets without a basic understanding about their function and potential impact. This blog will hopefully shed a little understanding on supplementation.

Our immune system is an amazing, yet complex system. It has one fundamental task, and that is to protect us from disease.

Before we go any further, let’s make one thing clear:


However, a healthy immune system is vital for fighting off all infections.

Here are the contents of topics covered by my Blog to ease skipping to any section you want to explore:

About Our Immune System

Basic Immune Function:

  • Our immune system is an amazing, complex part of our being with one fundamental task – to prevent our body from being overwhelmed by infection.
  • There is no doubt that we need to take responsibility for our own health and indeed, supplements may help support immune function and protect our health. 
  • However, many of us take them without a basic understanding of their function, side effects, interactions with other medicines and potential impact.
  • Every day of our lives there are a range of what are called pathogens that threaten our body, therefore the scale of the task placed upon our immune system is huge.
  • Depending on the baseline of our general health and wellbeing, together with the presence of co-existing illnesses, could potentially put immense pressure on our immune system. 
  • Could some people therefore benefit from taking supplements to support and assist maintaining our immune system?

Please Note: This blog is an advice guideline only.  

Supplements -The Basics

Some important facts:

  • Supplements are something we take to enhance or support our existing immune system. 
  • We must be aware that most of them are already in our bodies and we naturally produce them or have them provided by diet. 
  • For various reasons, our natural levels can often be depleted. 
  • Not all of us will need to take supplements, and certainly not all of us should rush out and buy all the supplements listed below. 
  • This article was written as a generalisation for immune support supplements and does not tackle the management or support of complex medical conditions.
  • Please remember a supplement recommended daily dosage (RDD) is only a recommendation. We do not necessarily all need to take the recommended dosage. 
  • Just like prescription medications, we are often prescribed different strengths and quantities for what we need. Some supplements can interfere with other medications/treatments. If you are on any treatment/medications then please consult with your health care provider before starting a supplement.
  • During this time, many of us are trying to enhance our wellbeing and stay healthy and are taking a multitude of supplements daily believing our bodies need them all.  
  • However, there is a possibility that you could be over supplementing.

Sometimes less is more;

More is not always better.

  • Taking too many supplements can often result in side effects just like prescriptions medicines.
  • We may end up with digestive issues, anxiety or sleep insomnia for example.  We can then often end up taking supplements to help cope with the side effects – a vicious circle!
  • Instead, it is important to start to be aware of how things make you feel.
  • If you wake up feeling great – do you really need to take your energy boosting supplement that day? 
  • Or the opposite, if you feel you need to take it and it has not worked, then have a think-  
    • How well did I sleep?
    • What have I eaten?
    • What quality of supplement am I taking?
  • The initial reason for starting a supplement may have changed 4-6 months down the line and perhaps you have now replenished what you felt you lacked and are now taking an excess.
  • Knowing when to take a supplement and when to stop again is a skill  but remember,  supplements should always add value to or enhance your health.  
  • You should dedicate time to ask yourself “How do I feel?” and assess how the supplement is working for you.


  • What time of day am I taking my supplements?
  • How much of the supplement am I taking?
  • Do not take all at once. Supplements do different jobs.
  • PLEASE BE AWARE that ALL supplements if taken over a long period of time, in excess may cause side affects. Some mild, some more serious. Never, unless authorised by your medical professional exceed the RDA daily doses.

If you are taking supplements it is important to dedicate the time to think how you feel, and how the supplement is working for you.

What Type of Supplement Should I Take?

  • Think wisely when choosing your supplements.
  • Unfortunately, many supplement brands use an inferior product, which together with the way they are produced will often result in an overall poor-quality supplement. Checking reviews is often a good way to see how well the product is received.
  • It is suggested that often a hard compact tablet will be harder for us to break down and absorb, so where possible we should opt for a powder capsule or liquid.

Appreciate the food that we have. We are what we eat.


  • Vitamin C is one of the most commonly supplemented nutrients relation to boosting our immune system.
  • Our bodies cannot make vitamin C so it must come from the foods we eat daily.
  •  Vitamin C is a powerful antioxidant that helps fight against free radicals in the body.

Vitamin C is found in a wide variety of fruit and vegetables, good sources include:

  • oranges
  • red and green peppers
  • strawberries
  • blackcurrants
  • broccoli
  • brussels sprouts
  • potatoes

How much vitamin C do I need?

The recommended daily intake of vitamin C for healthy women is 75 mg per day (120 mg per day for women who are pregnant or breastfeeding).

For adults, the tolerable upper intake level (UL) is set at 1,000 milligrams per day – the highest daily intake likely to pose no risks – is 2,000 mg per day.

What happens if I take too much vitamin C?

  • stomach pain
  • diarrhea
  • flatulence 


  • Vitamin D plays an extremely important role in our immune system.
  • Research has proven, we in the UK should all be on a daily intake of Vitamin D since our bodies do not receive enough of this vital vitamin on a daily basis, mainly from sun exposure and diet.

How Vitamin D Impacts Your Immune System:

  • Vitamin D reduces our risk of infectious disease by strengthening our immune system.
  • Your body takes a long time to absorb and process vitamin D, so the benefits will not be instant.

Vitamin D can be found in a small number of foods -Sources include:

  • Oily fish – such as salmon, sardines, herring and mackerel
  • Red meat
  • Liver
  • Egg yolks
  • Fortified foods – such as most fat spreads and some breakfast cereals

How much Vitamin D should I take?

  • Daily vitamin D intake of 1000–4000 IU, or 25–100 micrograms, should be enough to ensure optimal levels in most people.
  • Short term – 4000 IU is the safe upper limit according to the Institute of Medicine (IOM).

Taking too many vitamin D supplements over a long period of time can:

  • Over time, taking excess levels of vitamin D ( can cause too much calcium to build up in the body (hypercalcaemia).


During infections Vitamin A plays an important role by boosting our immune system to help protect against illness and infections.

Foods highest in vitamin A are:

  • Egg yolks
  • Beef liver
  • Liverwurst
  • Butter
  • Cod liver oil
  • Chicken liver
  • Salmon
  • Cheddar cheese
  • Liver sausage
  • King mackerel
  • Trout

Other foods include:

  • Sweet potatoes
  • Pumpkin
  • Carrots
  • Kale
  • Spinach
  • Dandelion greens
  • Cabbage
  • Swiss chard
  • Red peppers
  • Collard greens
  • Parsley
  • Butternut squash

Recommended Daily Allowance (RDA) for Vitamin A:

  • 900 mcg and 700 mcg per day for men and women, respectively — which can be easily reached by following a whole-foods diet.
  • It is important not to exceed the tolerable upper limit (UL) of 10,000 IU (3,000 mcg) for adults to prevent toxicity.
  • Since vitamin A is fat-soluble, it is stored in your body and can reach unhealthy levels over time.

Too much Vitamin A:

Long term excess levels of vitamin A supplements – often referred to as hypervitaminosis A.


  • A paper published in Infectious Disease Journal (Article ID 246737) found Vitamin A and vitamin D have a relationship.
  • It is vital that our vitamin D levels are healthy before supplementing with vitamin A.
  • The research showed that:
    • Low levels of Vitamin D, and high levels of Vitamin A can be counterproductive for our immune system.
    • If we have low levels of Vitamin D, then we may react negatively to a high dose of Vitamin A.
    • If we take vitamin D, then our body will be able to absorb more vitamin A.
    • If we have been taking Vitamin A without Vitamin D, then we may not be benefiting from the Vitamin A, and should consider stopping the Vitamin A until our levels of Vitamin D are boosted.


Selenium and Our Immune System

  • Selenium may be one of the most under-appreciated immune supporters in the human body.
  • It plays an essential role in our body’s response to viral infection.
  • Without adequate selenium in our body, our immune system and liver which helps remove toxins will remain vulnerable to attack.
  • If we do not get enough selenium in our diet we are more likely to come down with frequent infections.
  •  It takes us much longer to recover from infections with low level Selenium.
  • It is important to note that some research suggests long term, and high dose selenium supplement may increase the risk of diabetes.

Foods high in selenium include:

  • Fish
  • Lean meats
  • Nuts

Recommended Daily Allowance (RDA) for Selenium:

  • Safe and beneficial doses of selenium in adults range from 100mcg to 400mcg daily.
  •  Many people will need to take more than 100mcg – 200mcg daily to get the best results.


  • Zinc is a nutrient that aids the immune system.
  • Your body cannot store zinc, so it is important to get enough on a daily basis.
  • If you are low in zinc, it may increase the risk of getting an infection.
  • The key is to take zinc within 24 hours of developing any cold/flu like symptoms.
  • When we have an infection, our body requires zinc to help fight the infection.

How much zinc do I need?

The amount of zinc you need is about:

  • For Men: 9.5mg a day (normal supplementation is about 15–30 mg)
  • For Women: 7mg a day (normal supplementation 10–20 mg in women)
  • You can use more zinc temporarily, to correct a deficiency.
  • It is important to note that if taking a zinc supplement on a long term basis then you should also take copper (2–3 mg) and manganese (5–10 mg) as zinc may start to deplete these essential mineral from our body.

Good Sources of Zinc Include:

  • Meat
  • Shellfish
  • Dairy foods – such as cheese
  • Bread/ cereal products – such as wheatgerm
  • Legumes
  • Nuts
  • Seeds
  • Dark Chocolate
  • Garlic


Taking too much of a zinc supplement may cause reactions in your body, such as abdominal pain, nausea, and vomiting.


What is Glutathione?

  • Glutathione is a sulphur-based compound produced naturally by the liver.
  • It is an essential antioxidant, and plays a key role in our immune health.
  • It should be abundant in our body, however unfortunately even if you eat and live a relatively healthy lifestyle in today’s world it is impossible to escape toxic chemicals such as daily air pollution, toxic environmental chemicals, and hormones in our food.
  • Glutathione helps to detoxify our body against pollutants, and support a healthy immune function so our body can defend itself against pathogens.
  • Glutathione helps to maintain vitamin C & E in their active forms. 
  • Without selenium, a trace mineral that also helps vitamin E work more effectively, the body cannot produce glutathione fully. 

There are two main ways to get glutathione in the body orally.

  1. S-acetyl form
  2. Liposomal form
  • Many supplements will just say Glutathione. Our bodies are unable to absorb this form, so it is important to make sure when buying that it is one of the above.
  • Glutathione supplements can be expensive.
  • Glutathione also helps the gut cell wall, therefore is a great partner when taking a probiotic.
  • It has been found to be highly important as an anti -inflammatory response in lung cells.

How To Take Glutathione

  • There is no Recommended Dietary Allowance (RDA) for glutathione. 
  • It is recommended that you should not start taking this as a supplement unless you have already been taking a multivitamin prior. 
  • The multivitamin provides the nutrients your body needs to support the glutathione. 
  •  Research suggests taking it before breakfast or lunch for approximately 3 days initially.  Start with a low dose, if you feel only slight improvements, then gradually increase the dose. 
  • NEVER exceed the dose stated by the manufacturer or recommended by your practitioner.
  • If you feel improvements, continue to take for 3 weeks and then stop. 
  • If you continue to feel great, stop taking Glutathione until you feel you need it again, an example given is fatigue or brain fog sensation.
  • If you feel worse when taking it, then stop and take a multi-vitamin and/or digestive enzymes for 2 weeks. Then try again. 
  • PLEASE DO NOT take digestive enzymes if you have a stomach ulcer, until it has cleared up.


Glutathione levels decline at a rate of 10% per decade of age after age 20. This decline accelerates after 45 years and could be up to 50% reduced. (Please see side note below)

Food to Boost Glutathione Levels:

Parsley is probably your best vegetable source of glutathione 

Sulfur-rich vegetables:

  • Garlic
  • Onions
  • Kale
  • Broccoli
  • Watercress
  • Cabbage
  • Cauliflower
  • Arugula
  • Bok/Pak choy
  • Brussel sprouts
  • Mustard greens
  • Radish
  • Turnip

Glutathione-rich fruits:

  • Grapefruits
  • Tomatoes
  • Avocados

Other Glutathione Sources:

  • NAC ( N-acetylcysteine )
  • Milk Thistle
  • Whey Protein
  • Selenium
  • Vitamin A & E
  • Vitamin B
  • Fruits high in vitamin C will help your body better absorb the glutathione.

Please remember that cooking any of these fruits or vegetables will destroy the glutathione levels. Eating them raw or steamed is recommended.

Foods Boost Glutathione:

  • egg yolks
  • poultry
  • yogurt
  • red peppers
  • oatmeal
  • whey germ
  • walnuts
  • asparagus

The immune system works best when we have a delicately balanced level of glutathione.


  • Magnesium plays a key role in the immune response.
  • Magnesium has been shown to reduce inflammatory markers in the body.
  • Magnesium may help promote signalling and communication between immune cells to defend the body as quickly as possible against pathogens, viruses and bacteria.
  • Magnesium has been shown to be a booster towards Vitamin D in an immune response.
  • Magnesium plays an important role in the synthesis of glutathione.

Good Sources of Magnesium

  • Magnesium is found in a wide variety of foods, including:
    • green leafy vegetables – such as spinach
    • nuts
    • brown rice
    • bread (especially wholegrain)
    • fish
    • meat
    • dairy foods

How Much Magnesium Do I Need?

The amount of magnesium you need is:

  • 300mg RDA – max 420mg a day for men.
  • 270mg RDA – max 320mg a day for women.

You should be able to get all the magnesium you need from your daily diet.

High intake of magnesium from supplements can lead to gastrointestinal problems:

  • Diarrhea
  • Nausea
  • Cramping


  • Probiotics are live micro-organisms that have many health benefits.
  • Probiotics are needed to support our gut and boost our immune system.
  • The health of our gut can really impact the health of our entire immune system.

The link between gut bacteria and your immune system:

  • Our gut and immune system share a very close relationship.
  • As much as 70-80% of immune cells are located in the gut.
  •  If we have an unhappy gut, this will impact our immune function.
  • Unhealthy food causes inflammation in the gut, which can trigger the immune system to go into overdrive.
  • Continuous repeated activation of the immune system from the above can cause it to become unresponsive when actually needed, allowing infections to take hold more easily.
  • An unhealthy gut, means we are unable to digest food fully, and therefore the absorption of vitamins, minerals and other nutrients essential for our immune system. Therefore it will not matter how much fruit and vegetables we consume. If we cannot digest it, we cannot benefit from them.
  • Probiotics boost our friendly gut bacteria.
  • Probiotics help to aid the digestion of food.
  • Probiotics help keep unfriendly bacteria at bay.
  • All of which are great news for our immune system.
  • In fact, one study showed that athletes who took a probiotic daily had 40% fewer colds than when they took a placebo.
  • Pathogens that enter our body tend to be fought off by our friendly bacteria.
  • A healthy gut with friendly bacteria creates a better environment for your immune cells to thrive.
  • This then leaves our immune cells free to fight off infections in other areas of the body, like the respiratory system for example.

Foods probiotics can be found in:

Look for fermented foods-

  • Sauerkraut, or other fermented type foods
  • Apple cider vinegar
  • Kimchi
  • Pickles
  • Miso soup
  • Tempeh
  • Keifer

Try to avoid yogurts with live cultures added to them.  These can be very sugary.

Probiotic Supplements

  • Supplements are a great way to ensure getting the friendly bacteria you may need.
  • Most probiotics used in health supplements are of the Bifidobacterium and lactobacillus strains.
  • When taking a probiotic supplement, it is important to consider your overall diet.
  • An unhealthy diet kills off friendly bacteria, so it can therefore also do the same to the probiotics you are taking.
  • Increase your intake of fruit and vegetables.
  • Decrease your intake of refined sugary foods, and inflammatory foods such as alcohol and red meat.
  • Foods with fibre can help the absorption of probiotics.

How Much Probiotic Should I Take?

  • This depends on why you need to take a probiotic, such as has your gut been depleted by antibiotic treatments or other medications.
  • Probiotics can range from 5 billion up to even 75 billion.
  • Generally, 10 billion is a good maintenance dose if you already have a generally good gut health.
  • The best time to take a probiotic is in the evening once we have finished eating for the day.
  • Probiotics are best taken when live.  These will be ones that once opened need to be refrigerated.

Possible Side Effects

  • If we are depleted of friendly bacteria, then when we start to take a supplement it is possible to experience:
    • Gas
    • Bloating
    • Diarrhea
  • This is due to gut changes in the gut microbiota and the result is more gas being produced than usual.
  • These side effects should clear up after a few days or weeks.
  • If taking a higher dose initially, then it is recommended to reduce the quantity, or stop taking daily.


What is Bee Propolis?

  • Propolis is a resinous substance that bees produce from materials collected from tree buds.
  • Research has shown that it has many healing properties including anti-microbial, anti-fungal, anti-viral and anti-inflammatory.
  • It is well known to have significant immunity booster effects.

How Do I Take Propolis?

Bee Propolis is available in several forms. These include:

  • Tinctures
  • Raw propolis
  • Propolis chunks
  • Oral Spray
  • Capsule form.

How Much Should I Take?

  • There is no specific recommended daily allowance of propolis and there are not enough human studies to determine how much propolis should be taken to support health conditions.
  • Currently the recommended internal dose of bee propolis is typically 500 milligrams once or twice daily.


  • People who are allergic to honey, bee pollen, royal jelly, conifer or poplar trees should not use propolis unless tested first by an allergy specialist.
  • Propolis may increase the risk of bleeding in people who take blood-thinning medications or who have bleeding disorders.
  • Since propolis may slow blood clotting, you stop taking propolis at least two weeks before any scheduled surgery.
  • If you have asthma, some experts’ advice avoiding propolis completely since it believed that some chemicals in propolis may make asthma worse.  However, there has also been research that demonstrates helpful effects of propolis for asthmatics. 
  • If you have asthma, speak with your doctor before taking propolis.
  • If you are pregnant or breastfeeding, check with your health care provider before taking propolis.
  • If you have any ongoing health concerns or are taking any medications, check with your health professional before using propolis.

Final Tips for Strengthening Your Immune System:

Even the healthiest of people get sick every now and then. By fine-tuning certain aspects of your health routine, such as diet and stress management, you can help support your immune system’s defenses against bacteria, viruses, and other pathogens that cause conditions like the common cold or flu.

  • Try to get adequate sleep and rest.
  • Even if you eat well, your immune system will suffer if you do not sleep enough or sleep well.
  • Make sure you have a healthy digestive system.
  • If you regularly suffer with gas, bloating, indigestion, constipation or diarrhea, it means something is very wrong with your digestive tract. 
  • If your digestion is poor, you will not absorb the nutrients from your food and nutritional supplements.
  • Try to get some regular and safe sunshine exposure.
  • Exposing your skin to the sun’s UVB rays enables your body to manufacture vitamin D.
  • Avoid sugar, or minimise your consumption of it.
  • Sugar weakens your immune system.
  • Sugar is food for bacteria, yeast and other pathogens.
  • Removing sugar from your diet will make it much easier to overcome an infection.
  • Do not forget to eat plenty of vegetables. You can include lots of veggies in a soup, stew, casserole or curry.
  • Drink water to keep hydrated.  If you have been poorly, sipping lemonade and water with electrolyte sachets can help restore salt/sugar balance.


  • Diet
  • Exercises
  • Reduce stress
  • Sleep
  • Herbs and supplement boost

The above blog post is not intended to diagnose, treat or cure any disease.


Please note: no content on this blog should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

Author’s note:

Multiple references were used for this article. 

If you would like details of any particular reference please contact me directly.

Dr Laura Nuttall DC

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top
%d bloggers like this: