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January 7, 2019

Food As Medicine

How to Ensure Bullet-Proof Immunity

There’s an old expression that says “an ounce of prevention is worth a pound of cure.” This couldn’t be more true. When we fall ill, we tend to shift into ‘fix-it’ mode so we can alleviate our symptoms as quickly as possible. What if we spent more time preparing our immune system to reduce the likelihood of getting sick in the first place, and readying ourselves so we are better equipped to deal with a bug should we catch one? By learning how to build a healthy immune system, we can be prepared for better short-term and long-term health.

The immune system helps protect our bodies from invaders and foreign materials. When it is working at full capacity, we usually won’t experience any symptoms. However, if we have a weakened immune system, we will most likely fall ill for a period of time. Sometimes illnesses are short, such as the common cold, while others can be chronic and life-altering like autoimmune diseases.

There are many ways in which we can boost the immune system to give us the best odds at maintaining our health. Here are a few suggestions that will help prepare your body to “fight the battle.”

Stay Away From the ‘White Devils’: Flour + Sugar

Foods made with white flour and white sugar cause a decrease in immune function. These foods are typically refined and often come in the form of store-bought, processed foods. These ingredients are also linked to inflammation, which can lead to many conditions – including autoimmune diseases. Evidence indicates that Western diets promote a multitude of diseases such as obesity, cardiovascular disease and metabolic syndrome, and these can hamper our body’s ability to function well.

White refined sugar is a dangerous substance that is stripped of vitamins and minerals, leaving our bodies with the extra work of metabolizing them without receiving any benefit in return. Groundbreaking research published in the journal Nature discovered sugar triggers cancer cell growth and actually helps them multiply much more quickly. You can read about how sugar affects the immune system in detail in my post Sugar + Cancer: What’s The Link?

What’s more, refined flour and sugar consumption can disrupt the microbiome (our colony of gut bacteria), sending us into dysbiosis. You can read more about how the microbiome affects immunity a little further below.

Eat Immune-Boosting Foods

Our dietary choices can have an enormous impact on our immune system. Certain foods can boost immunity, while others can help modulate it. Malnutrition and nutrient deficiencies can also impair immunity. Generally, a diet rich in whole foods like vegetables, fruits, quality animal products (meat, fish, poultry, eggs), nuts, seeds, legumes and gluten-free whole grains are going to help sustain a healthy immune system. However, there are some immune-boosting superstars that I like to introduce to clients and why:

  • Onions and garlic –  antimicrobial, antibacterial and antiviral properties, also anti-inflammatory
  • Berries – sources of flavonoids that are anti-inflammatory and immune-boosting, contain fibre to support the digestive tract and in turn the microbiome
  • Citrus – contains Vitamin C for immune defense, protection against pathogens and infections
  • Mushrooms – modulate the immune system, dialing it up or down as needed
  • Ginger – highly anti-inflammatory and has anti-oxidant effects that protect against diseases
  • Fire Cider – a very potent mix of garlic, onions, horseradish and ginger that helps to dampen infections quickly
  • Bone Broth – rich in minerals and amino acids that nourish the gut and encourage healing, anti-inflammatory
  • Turmeric – highly anti-inflammatory and can help to modulate the immune system by activating the beneficial immune components while down-regulating the inflammatory ones
  • Coconut Oil – anti-microbial and anti-bacterial
  • Greens – an overall vitamin and mineral-rich category that is also rich in B-vitamins for energy and nervous system function
  • Wild salmon – high in anti-inflammatory omega 3 fats, and a good source of protein (protein helps to support and modulate a healthy immune response)

Support Your Microbiome

About 70% of our immune system lives in the gut, in gut associated lymphoid tissue (GALT). Increasingly, researchers are learning more about our microbiome – the community of bacteria that live inside of us – and determining how it affects our immunity and a variety of common health conditions. Microorganisms outnumber us by about 10 to one, and we have about 100 trillion bacteria living inside of us. That means we need to ensure all of that bacteria gets along well. To put it another way, if you’re having a party you probably want to invite more polite, respectful and interesting conversationalists than the rowdy folks who may damage your home. In our bodies, we want more beneficial bacteria than damaging bacteria.

Evidence indicates that beneficial bacteria help to ‘train’ the immune system so it knows what pathogens are friend or foe, produce beneficial nutrients and keep the bad bacteria in check. Our children inherit our microbiome from us; our dietary choices impact their ability to develop a functioning immune system.

One of the ways we can help ‘seed’ our microbiome is through a good probiotic. These can help improve digestive function, boost immune function, benefit the brain and our moodreduce our need for antibiotics, and may even prevent the common cold.

Other basic good-digestion tips that will help your gut health:

  • Consume soluble and insoluble fibre
  • Drink water
  • Eat fermented foods (sauerkraut, pickles, dairy-free yogurt/kefir, etc.)
  • Eat prebiotic foods (jerusalem artichoke, garlic, onions, leeks, dandelion greens, etc.)
  • Don’t overuse antibiotics
  • Chew your food well
  • Use digestive bitters alongside meals
  • Reduce or eliminate refined sugars

Get Enough Sleep

A good night’s sleep is crucial to our mental and physical health. Lack of sleep depresses our immunity – in one study of identical twins, researchers found that the blood samples of the sleep-deprived twin showed a lowered immunity compared to the twin who slept. Insomnia can lead to activation of the pro-inflammatory cytokines, leaving us more susceptible to infections. It isn’t just the amount of sleep, but when that sleep happens. Our bodies follow a natural circadian rhythm, where certain hormones are released throughout the day. Studies of shift workers indicate that they are more likely to develop infectious diseases due to their sleep patterns.

Another interesting aspect of sleep and immunity is that quality sleep allows us to develop a long-term ‘memory’ of pathogens, which helps our immune system recognize and respond to infections more quickly.

To facilitate healthy sleep:

  • Make sure it’s dark in the room.
  • Turn off all devices at least an hour before bed.
  • Avoid sugary foods and caffeine in the afternoon and evening.
  • Sleep in a cool room.
  • Create a consistent bedtime.
  • Practice relaxing bedtime rituals – meditation, reading, aromatherapy, baths, etc.


Exercise boosts the parts of our immune system that fight infections, reduces inflammation and increases our circulation, allowing the immune system to work much more efficiently.

The best exercise is the exercise you’ll actually do. Go for a run, a bike ride, do some yoga, lift weights or play squash. If you are an animal-lover, adopt a dog and go for a walk, if that’s what it takes. Whatever you do, do something. The best way to get started is to just get started! Having a friend join is helpful, too.

Get Some Vitamin D

Many people don’t realize how important vitamin D is to the function of the immune system. Our immune cells have Vitamin D receptors, and it helps to modulate our immune response, prevent infection and protect against autoimmune diseases. In places where the populations have less sun exposure, there is a higher incidence of many illnesses. Why? Many people are deficient in vitamin D and so have compromised immune function.

We get vitamin D when the UV from the sun reacts with the cholesterol in our skin. People with darker skin tones need 3-5 times longer exposure to the sun than people with lighter skin tones. Many of us also wear sunscreen, preventing vitamin D production in the skin. If you are unable to get out into the sun during non-peak hours, try vitamin D supplementation instead.

Reduce and Eliminate Stress

Many of us deal with a constant stream of stressors and our ability to process stress also impacts our immune system. Short-term stress can be beneficial, while long-term stress leads to a suppressed immune system and chronic inflammation, plus it increases our susceptibility to infections.

One review of 20 clinical trials found that practicing mindfulness meditation can help reduce inflammation and boost cellular defense, while an analysis of women on a yoga/meditation retreat found that meditation helped induce relaxation and improved immune function. Another study of deep breathing techniques showed that it can boost our anti-inflammatory chemicals and dampen the inflammatory ones.

Aside from meditation and deep breathing, you can process stress through:

  • Being in nature
  • Writing or journaling
  • Talking with loved ones
  • Gentle exercise
  • Creating a calm work and home environment

Avoid Genetically Modified Foods

Genetically modified foods (GMOs) can suppress the immune system, trigger allergies and disrupt the digestive tract. You can read a full, detailed report about GMOs here. Some of the most highly modified foods are corn, soy and vegetable oils. There is a lot of controversy surrounding GMOs and from my perspective, we don’t have enough long-term data to determine whether or not they are safe.

There are many different components to supporting a healthy immune system and by incorporating the above advice you have a better chance of feeling well and vibrant throughout the year. Grab my free download to Immune Boosting Do’s and Dont’s to start boosting your immune system today!