Immune Insufficiency

immune insufficiency quiz

This page is designed to help you understand why you might be experiencing symptoms relating to immune insufficiency. In this section we look at what role the immune system plays, possible underlying causes for reduced immune function, testing considerations, and some things that you might be able to do to help improve the robustness of the immune system through some foundational nutrition and lifestyle adaptations.

What does the immune insufficiency section relate to?

Immune insufficiency is a broad term which can mean that the immune system is not responding as expected and perhaps not functioning properly.

Our immune system serves to protect us from things that might cause infection and it also plays a role in repairing us from injury as well. If the variety of cells that make up the immune system are not functioning properly, this can leave us open to illness or impaired recovery.

Those with mild immune insufficiency may find that they find it hard to shake off infections/illness, stay sick for longer or perhaps, constantly feel a little unwell or having ongoing infections.

Others may be classified as immunodeficient or immune suppressed. Those in these categories have a further risk of getting an infection and becoming sick.

It is important to understand that we can be immunocompromised at different levels, meaning the immune system is not either on or off. Therefore, the more robust and in balance your immune system is, the less likely you are to have issues with it.

If there is one thing that the COVID global pandemic has taught us, it’s how different people respond to the same challenge. But ultimately, the older you get or the more underlying health issues you have, the more likely you are to have negative reactions to such a virus and therefore you may find you need to battle much harder and for longer with the symptoms.

Having a healthy immune system is a fine balancing act. An immune system that is compromised can cause issues, as well as an immune system that is over responsive too. Our focus will be on the foundational things that we can do to help bring balance to the immune system and in relation to this particular section, what we can do to support overall immune function.

What are some of the causes of immune insufficiency?

Considering that immune insufficiency is on a spectrum of what might contribute to immune issues, it is important to state that some of the causes below are obviously far more aggressive on the function of the immune system than others.

For example, some of the issues that can result in the immune system becoming more compromised include:

  • Having a pre-existing medical condition such as cardiovascular conditions, lung disease, diabetes, cancer and HIV
  • Autoimmunity can upset the balance of the immune system. Some aspects of the immune system may be hyper-responsive and others not so much. Also, for a large number of people with autoimmune conditions, the drugs of choice are immunosuppressants
  • As discussed in the point above, certain medications, treatments like radiation therapy, chemotherapy etc can all significantly impact the immune system
  • Advancing age
  • Higher levels of body fat, being overweight or obese
  • Poor dietary habits
  • High levels of stress
  • Inadequate levels of sleep
  • Over exercise / under recovery
  • Lack of exercise or being particularly sedentary

Testing considerations for immune health

In this section I am going to focus on more basic testing to assess immune health. For more complex immune testing, I leave to an immunologist.

The good news is that many of the basic immune based labs can be ran through your GP or quite inexpensively via a private lab.

One of the key areas to look at are what are known as ‘Acute Phase Reactants’. Acute phase reactants tend to increase during inflammation and/or infection. Examples of acute phase reactants include C-Reactive Protein, Ferritin, Fibrinogen etc. When elevated this can signify acute infection/inflammation.

You also have what are termed negative acute phase reactants. These will tend to decrease during infection or inflammation, and they include albumin, transferrin and possibly cholesterol.

Below, I am going to take you through the most common immune related markers that I look at, which are easily accessible and generally cheap to run or something that your Dr will be able to run for you. I will also state with these markers what either high levels or low levels might mean from an immune perspective.

White blood cells and differentials

White blood cells are cells of the immune system that are involved in protecting the body against infection and foreign invaders.

The white blood cells are divided into two subgroups. Granulocytes, consisting of neutrophils, basophils and eosinophils. Then the other subgroup known as agranulocytes and these are the monocytes and lymphocytes.

When running a haematology assessment with differentials, the above markers will be present.

High levels of white blood cells are normally seen with acute infection, illness or states of high inflammation. It can also increase with acute stress, late pregnancy, allergy/asthma and a few other medical conditions.

On the other hand, low levels of white blood cells can be linked with chronic infections such as chronic viral, bacteria infections.

Therefore, just from looking at the white blood cell levels, we can get clues for acute vs chronic immune issues. Those who are immune compromised, may find they have very low white blood cell levels.

Beyond just looking at the white blood cells, you then look over the types of white blood cells for further clues, neutrophils, lymphocytes, monocytes, basophils and eosinophils.

Below I am going to summarise the immune specific issues that might be related to highs and lows in those specific white blood cells.


  • High neutrophil levels can point towards acute viral or bacterial infection as well as high levels of inflammation.
  • Low neutrophil levels can point towards chronic viral or bacterial infections.


  • High levels may be the result of an acute or chronic viral infection, acute bacterial infections, Crohns disease, autoimmunity and high inflammation.
  • Low levels are seen with chronic infection or potentially suppression of bone marrow production of these types of white blood cells.


  • When high, this can indicate the recovery phase of an acute infection but may also be the sign of intestinal parasites. It can also be elevated with Ulcerative colitis and Rheumatoid Arthritis.
  • Low levels are typically associated more with immunosuppressant medications.


  • High levels are associated with non-specific inflammation and possibly intestinal parasites.


  • High levels may result from intestinal parasites, food and environmental allergy or sensitivity, asthma, gastroenteritis.
  • Low levels can result from stress.

So, from just these markers you can see how we can determine a number of possible immune related issues.

Other markers we look for

  • Ferritin – elevated levels can result from inflammation/infection.
  • Platelet Count – Unexpected increases above normal reference ranges may relate to cancer, certain autoimmune conditions, stress, infection and inflammation.
  • Albumin – When decreased can be a sign of infection/inflammation.
  • Globulin – When elevated can be a sign of acute inflammation or infection and potentially certain types of autoimmune conditions. When decreased can be a sign of a compromised immune system.
  • ESR – When high can be a sign of inflammation, certain cancer, cardiovascular and musculoskeletal conditions, inflammatory bowel issues.
  • C-reactive protein – Increases after tissue injury, inflammation or infection.

As you can see from above, the most important assessments are that of the white blood cell count, and the breakdown of those white blood cells to rule out significant immune insufficiency. However, you do not need to be clinically immune compromised to feel like your immune system is not functioning optimally and for that reason, we must also rely upon the symptoms and history that someone presents with.

How can you improve your immune function?

Below are some initial nutrition and lifestyle recommendations to support the function of the immune system.

Managing psychological stress

Whilst acute stress can result in an adaptive increase in your immune response, chronic stress can result in an overall suppression of the immune response.

Past traumas, significant life events and just general day-to-day living can provide significant psychology stress.

I have seen time and time again the impact of chronic stress on the ability to deal with chronic digestive issues due to compromised gut specific immunity. Not only that, but chronic psychological stress is also known to suppress cellular measures of immune function.

Managing psychological stress is a big subject as we can be exposed to so many stressors these days, past and present, that are impacting us. It is about taking a step back, sometimes with the help of a professional to see where you might be able to make some initial changes that would help to lower your psychological load.

This is one of the key reasons we have professionals within our team, and a wider practitioner network that specialise in working with psychological stress and trauma. It will often help to sit with someone neutral to discuss past and present life stressors, even if they are just holding a space for you to work through your challenges and then slowly coming up with strategies to help lower the stress load.

Optimising Body Composition

Higher levels of body fat, especially visceral fat (the fat that surrounds our organs), is strongly correlated with low grade systemic inflammation. The fat cells themselves activate certain aspects of the immune system but equally suppresses other aspects of the immune system. This can leave someone prone to imbalanced responses to immune challenges resulting in complications to infections.

Obesity also increases the risk of developing many other diseases such as cardiovascular disease, diabetes, cancer and more. Each of these are also linked with inflammation and immune issues.

We tend to recommend that all males should be below 20% body fat and all females below 30%. More optimal ranges for males might be below 15% and females typically somewhere between 22-28% body fat. In both instances we always want to see the visceral fat levels well within normal or optimal ranges. Of course, these numbers vary a little depending on the levels of muscle mass and water; therefore, these have to be taken into consideration when looking at individualising body fat percentage goals.

At the clinic we have the luxury of assessing body composition rather than relying upon just weight, circumference and Body Mass Index (BMI) measurements.

Get enough sleep

A lack of sleep is linked with a higher risk of sickness. Past studies have demonstrated with reduced amounts of sleep, especially anything below 6 hours a night, increases the likelihood of catching a cold and makes your immune system less resilient to infections.

Adults should be aiming for 7-9 hours of sleep, whilst teenagers more like 8-10 hours and infants around 14 hours a day.

Quality of sleep is also very important. The invasion of technology into our lives in the last 50 years or so, means that we have near constant exposure to blue light. This blue light can supress the production of the sleep hormone melatonin, leading to reduced sleep quality. Try where possible, to minimise exposure to blue light sources in the hours leading to bed, this means less time on laptops, watching TV, phones etc.

Review your evening routine and current sleep habits and quality, and factor in if this is an area that can be improved to improve overall immune function.

Optimise your diet

Our diet provides the building blocks for us to make immune cells, as well as supporting microbes that can help us retain a more robust immune system. Below are some basic entry point nutrition recommendations to support overall immune function:

  1. Eat colourful plant-based foods. This means lots of vegetables, some fruits, herbs and spices, as these are a good source of antioxidants and anti-inflammatory compounds that can assist the immune system.
  2. Maintain optimal protein levels – Protein is critical for the immune system. Make sure that your protein intake keeps up with demands. The more you exercise or the more stress you have, typically the more protein you require. Protein requirements often increase with age as the digestion and absorption of protein rich foods can diminish.
  3. Eat more anti-inflammatory fats, particularly the emphasis on omega 3 rich fats, as these may help to manage chronic inflammation in the body. Omega 3 fats include sources such as oily fish, chia and flax seeds, seaweed etc.
  4. Reduce the intake of more pro-inflammatory fats such as arachidonic acid, a type of omega 6. Highest levels are found in high fat animal products, although the animal products that also provide a good source of EPA, a type of omega 3 are less of a concern, such as oily fish, grass fed meats etc. I would however limit the intake of high fat dairy products, commercial raised meats and definitely lower the intake of refined/process vegetable oils like margarine, deep fried foods etc.
    Consider the inclusion of probiotic foods such as kefir, kombucha, kimchee, sauerkraut, yoghurts etc. Beneficial bacteria have been shown to support general immune function, meaning you are more likely to mount an appropriate response to an immune challenge, especially at the mucosal levels within the gut, mouth and nasal area.
  5. Reduce the intake of refined sugar. Not only is this more likely to contribute to weight gain, but it has also been linked with acute negative influences on the function of the immune system.
  6. Avoid significant caloric excess or caloric deficits, both can be stressful on the body.

Get some sunshine and optimise your vitamin D

Sun exposure is your best bet to optimise your vitamin D levels naturally. Whilst some foods contain a little vitamin D, it is very small comparative to the influence of sun exposure.

If you struggle to get adequate sun exposure, perhaps because of where you live, a job or life circumstances that requires you to be indoors a lot, then it is definitely worth assessing your vitamin D levels and then considering supplementation to optimise vitamin D. I like to aim for around 100-150nmol/l as an optimal blood level of vitamin D.

Optimise certain micronutrients and supplement wisely

Firstly, it has to be said that there is not one single magic pill.

Nutrient deficiencies or insufficiencies are a leading cause of a depressed immune system. Below I am going to review specific nutrients that may help to improve immune function, especially if your nutrients status is sub-optimal.

Whilst complete deficiencies are quite rare these days, nutrient insufficiencies are somewhat common. Below are some nutrients that can support immune function.

Vitamin A

Vitamin A plays a role in supporting the integrity and structure of the digestive lining, as well as the skin and respiratory barriers. These barriers act as the junction between the outside world and our inner body. Breakdown of these barriers can result in foreign invaders getting into the body and increase the risk of infection or heighten immune response and inflammatory reactions.

Vitamin C

This nutrient has long been associated with immune health. It has been shown to have anti-bacterial and anti-viral capabilities. It has been shown to reduce the severity and duration of colds and useful in modulating responses to stress, however higher levels of stress can deplete levels of vitamin C more readily.

Vitamin D

Vitamin D is crucial for optimal immune function. Something that is hard to get from food and relies upon sunlight exposure. This means that it is a common insufficiency. Vitamin D is involved in the following:

  • Improves the clearance of bacteria at various barrier sites in the body and in immune cells.
  • Reduction of the frequency of viral infections specifically impacting the upper respiratory system.

Aiming for optimal levels of vitamin D is important, thus assessing vitamin D status is advised especially in the winter months. Vitamin D supplementation can then be judged accordingly.

Vitamin E

This vitamin has been shown to increase white blood cell response and enhance other cells in the body that deal with infection. As we get older, supplementation of vitamin E may be particularly beneficial. In one study, supplementation of vitamin E at 200iu per day demonstrated a protective effect against upper respiratory tract infections and in particular the common cold.

Vitamins B6, B9 (folate) and B12

These nutrients are all involved in white blood cell production and formation of healthy white blood cells. They are the cells involved in fighting and preventing infections. Unfortunately, these are common nutrients to become insufficient and for genetic reasons, some people may require more support with these nutrients compared to others, especially with lifestyles and nutrition habits that are sub-optimal.


Zinc has long been associated with immune health and for good reason. It has been associated with the destruction of foreign bugs and is required for the white blood cells to function correctly.

Zinc is also involved in the inhibition of viruses. Zinc lozenges in particular have been shown to help with the common cold.


This mineral supports the production of the enzyme glutathione, often known as the mother antioxidant. Antioxidants play a crucial role in supporting your immunity and protecting your cells from damage. In particular, it is important to protect important immune related organs from damage, such as the thymus gland.

Based upon the above role of vitamins and minerals in supporting our immune system, a high-quality multivitamin and mineral formula may be a good idea for some individuals, in particular those with high demands on their body such as those with significant amounts of physical and mental demands. Please remember though, that the foundation to optimal nutrient status is healthy nutrition choices and a healthy digestive system.

Taking vitamins and minerals without addressing areas such as your general nutrition, sleep, stress, movement and relationships, is like building a boat out of rotten wood and golden nails.

1-2-1 Support

We hope this provides some general insight into immune health. For those looking to get a more bespoke approach, you can also work 1-2-1 with members of our team who will be able to facilitate nutrition and lifestyle changes, as well as run a number of the advanced tests to help determine risk and guide your approach.

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