Yes, you can boost your immune system. In this blog post I look to review evidenced-based ways to boost your immune system. These are well documented, easy to achieve actions anyone can use. I see these as the basics. These should be our go-to’s when we need to reset our immune system and give ourselves the edge in a complex environment (ie. if we know we are going to be around those who are coping with illness). 

 

These techniques/categories of support are meant to be safe and easy. Many of my patients are immunocompromised (they have lower immune function than those without disease) and are looking to optimize their immune function. For this reason I decided to gather the most widely accepted principles of immune boosting to present. 

 

Of course, at this time in history it goes without saying that physical distancing and proper hygiene are very important, not only during this pandemic. Being mindful of those around you, who you might be impacting or spreading pathogens to, and what the implications of your lack of hygiene might be is very important to consider. 

 

Immune Support and Stress Reduction
Most of us would agree that stress weakens the immune system but when deciding to put together this article I had to ask myself, “where is the evidence?” Here are the details: stress does weaken the immune system and at the same time can dysregulate the immune system (ie. make it do things it shouldn’t do). High profile studies recognize this.

 

What a genius idea researchers had when they decided to study students' immune systems during exams to assess if there were any changes from baseline. If you have been in a high pressure exam situation you know how depleting it can be. During stressful periods like these researchers noted that immune function reduced making the students more prone to infection. I think about this all the time. It wouldn’t only apply to exam periods. It could be during stressful work cycles, intense emotional stress, trauma, etc. This really highlights the self care that we need to participate in after intense stress. 

An interesting way to assess immune responses is to look at how an individual’s immune response is activated by a vaccine. A study on caretakers for dementia patients showed that they had less antibody response from a vaccine compared with those not looking after dementia patients. We know this is a stressful job but the fact that simply being in that role is immune weakening is astonishing. High stress hormones were also present in the current caregivers with the lowest vaccine response. 

 

So, what does this tell us? It suggests that our immunity, or potential to mount a lasting response to a pathogen, is weakened by stress. We will have less protection in the moment if we are stressed while also less prolonged protection against the same organism. 

 

In general, keeping stress low allows for proper immune response. This doesn’t mean we need to avoid all stress in life. It simply means we need to build resiliency around how we cope, develop coping techniques, be easy on ourselves when in stressful times and do everything else possible to keep immune function optimal. 

 

In 2019 the Journal of Sport and Health Science published a study showing how exercise provides an immediate immune boost. This might seem counterintuitive to some. I know it did to me. My inclination was that exercise had a short term suppression of the immune system which was followed by a boost. This was fueled by reports about intense exercise and immune suppression. After reviewing these studies in detail I was able to learn the specifics. Here they are:  

 

All you need to remember is “immune suppression begins when workouts are more than 60 minutes at more than 60% intensity”. Beyond this is where immune suppression occurs. 

 

This means if we are doing workouts at greater than 60% intensity for less than 60 minutes we will have an immune boost. Also, if we exercise for longer than 60 minutes (ie. walking) at less than 60% intensity we are likely to achieve an immune boost as well. 

 

It is not as difficult as I once made it seem. 

 

The majority of people do not have enough time or physical capacity to over-exercise. Do not worry about overtraining negatively impacting your immune system. 

 

Do consider how each exercise routine provides support for your innate immune system, that part that is readily available to handle what you are exposed to. If you need support today, exercise. If you need ongoing support, string together a series of workouts. They are immune boosting and the more consistent you are the better your immune system will be supported. 

 

Have you ever been burnt out from overwork and then developed a cold? It is an all-to-familiar occurrence for us. Sometimes life calls for a period with lack of sleep. This reduces immune function.

 

What is the level in which insomnia or lack of sleep quality affects the immune system? A survey on 22,000 Americans reported incidents of head colds, pneumonia, ear infections and flu in the previous 30 day period and their sleeping habits. Of those people 13% reported sleeping 5 or less hours per night, 23% for 6 hours, 56% for 7-8 hours and 7% for 9 hours or more. Among those who slept 6-9 hours, no association with negative immune pact was observed. Those who had existing sleep disorders and less than 5 hours of sleep were more likely to have a head or chest cold. 

Immune recovery is like muscle recovery. We need a break from exposure (ie. movement for muscles) in order for recovery to take place. For the immune system it seems like stringing sleeping events that are longer than 5 hours is the sweet spot (based on this observational study). 

 

There are some other considerations here to think about. Were those sleeping less than 5 hours also more stressed, eating poorly and not exercising? Did they report 5 hours total or 5 hours in a row of sleep time? When they had periods of better sleep did they have less head colds? 

Regardless, sleep is important and maintaining adequate sleep is essential for maintaining solid immune function. Immune system dysregulation can begin with lack of sleep and its consequences can be severe. 

 

Here is my sense of what is going on: What I see in my practice is that when people don’t sleep well enough they eat poorly because they need to find more calories to give them energy. Increased calorie consumption will suppress immune function. 

 

Shoot for 7 hours straight minimum nightly and if you are over 18 no more than 9 hours in a row per night (younger people need a lot more sleep). 

Immune Support and Nutrition

People come to me and ask if they should be taking high dose vitamin C or D. A really important question. People ask if they should take zinc everyday. I get questions about astragalus, echinacea, medicinal mushrooms and other herbs for immune support. I love when people want optimal, when they want to go the extra mile for immune support. 

We use those individual nutrients, herbs and different combos on an individual basis. For many people there can be value. Many people are not achieving adequate levels of nutrients in their diet and they need to be supplemented. 

There is evidence for the prevention and treatment of viral infections through the use of certain supplementation. Several controlled trials showed that zinc is effective against infection in the elderly population. One study on a daily dose of 20mg of zinc and selenium showed a significant decrease in infections in institutionalized elderly people, with subjects aged 65+.

 

Another study showed that subjects deficient in zinc, when supplemented, showed a reduction in common colds. We know that the elderly are commonly deficient in zinc and when they take supplements, there is a likely immune benefit. If you have a blood test that shows low zinc levels, there is likely a benefit to taking zinc to reduce a common cold or illness. Does that mean everyone should take zinc? No, it does not. Nutrients need to be taken on an individual basis on the advice of your healthcare provider.

What we do know is that poor diets that do not include a broad spectrum of nutrients reduce immune function. In populations of the world where nutritional requirements cannot be met, the susceptibility to infection is higher. Here are the principles I consider when building a diet for immune support:

 

Follow these principles and generally you will get what you need. 

We need a well balanced diet but there is a limit. You can have a well balanced diet but consume too many calories. Too many calories can suppress the immune system. Overeating is bad for immune function. 

 

The other nutrient on everyone’s minds is Vitamin D.

The Canadian government has been recommending vitamin D for several years and it is important to note Health Canada guidelines support its use. 

 

Vitamin D is used in many cellular processes including immune cell function. Deficiencies can be dangerous. If going from low vitamin D status to normal vitamin D status through supplementation we can see a reduced incidence of infection. If levels are normal, taking more may not help reduce the risk. 

Low vitamin D levels are associated with worse outcomes from infections. Vitamin D concentrations less than 50 nmol/l (i.e. <20 ng/ml) have a 64% increased risk of community-acquired pneumonia and those with the lowest levels, generally below 30 nmol/L, have an increased risk of worse outcomes from pneumonia. More studies need to be done for its use in treatment but we know for sure that increased susceptibility to infection is associated with low levels of vitamin D. 

 

People with low vitamin D are more likely to get an infection. 

 

Where I stand right now: Know your Vitamin D3 level. 

 

When levels are taken into the normal range immune function improves. This is through multiple mechanisms, including specific antiviral, bacterial and immune regulating pathways. When you get tested, you can know where your vitamin D levels are and can learn how much supplementation you should take and for how long. 

 

It is important to note that it can take up to three months to reach a normal level if in a deficient state. I recommend starting with what is generally recommended for your age and then being tested to know if there is value in higher doses. 

Immune Support and Weight Control

Diet induced obesity impacts and impairs both innate (immediate) and adaptive (preventative) immune response. 

 

Innate response is when your body’s immune system deals with a threat from an infection using a system that is non-specific, ie. something bad enters you haven’t seen before, the immune system deals with it. Being in an obese range on the Body Mass Index scale reduces the effectiveness of the innate immune system. 

 

One more time for effect: The immediate immune response, which we all depend on for daily protection, is not as efficient if you are of an unhealthy body weight. 

 

When talking about immune defence, exercise, sleep and stress are all important factors to consider but weight control absolutely needs to be at the top of the list. 

 

Need an immune boost this winter? Achieving a healthy weight should be a top priority when thinking about how to improve the immune system.

 

That’s not all. When it comes to adaptive immunity, or developing a protective immune response for future use, normal body weight status is important too. A study on animals from the University of Texas tested the immune system’s adaptive function in lean, normal and overweight mice. The mice only differed in their body fat; the mice were given a vaccine to stimulate immune response. Following the vaccine, the mice with the highest body fat had the worst immune responses to the vaccine and therefore the worst “memory” immune system. 

 

Double down on staying lean. Exercise and nutrition are the first two pillars of weight control.

How to optimize immune function right now?

Now, more than ever, we should make immune support a priority. For some that might mean considering nutrient support like vitamin C, zinc and vitamin D. For all it means we shoot for optimal wellness through lifestyle medicine. 

Beyond hygiene and distancing we need to sleep well, keep stress low, exercise, watch our weight and eat healthy. 

Consult your naturopathic or medical doctor for advice and strategies to improve your specific immune system.

 

Putting it all together:
- Stress reduction - practice techniques daily to keep stresss low
- Exercise - participate in daily exercise. Use a mix of endurance, strength and high intensity workouts
- Nutrition - eat a balanced diet with lots of fruit, veggies, whole grains, lean protein and clean fats
- Sleep 8 hours per night with minimal interruptions
- Weight Control - achieve a healthy weight as soon as possible

 

Evidence informed immune boosing principles suggest that you should optimize these 5 categories. If you are thinking about going the extra mile with immune optimization this Fall, first make sure that you have your basics covered. 

Thank you for reading. I look forward to writing more about what you can do to support your health and immune system.

 

-Dr. David Duizer ND