Strong immunity has never been so important. With so much uncertainty about the future, the best thing you can do for yourself – and those around you – is to keep well.
Fortunately, that’s easier than you might think. With a few changes to your diet and lifestyle, you can not only prime your body’s defences against bacteria and viruses but improve your overall health and wellbeing.
Even if you eat a healthy diet, a healthy lifestyle is crucial to supporting proper immune function. A few simple lifestyle changes can make a huge difference to your overall wellbeing.
In this article, I'm going to take a look at the best supplements, foods, and lifestyle changes for a healthy immune system!
Boosting your immune system should begin with supporting your gut microbiome.
Probiotics are live beneficial bacteria that play a major role in supporting your immune defences. Your gut microbiome is crucial to the functioning of your immune system. At least 70 percent of your immune system cells reside in the walls of your gut. These ‘good’ bacteria work by ‘crowding out’ harmful bacteria and yeasts. Probiotics also help you to digest and absorb vital nutrients from your food.
Research has shown probiotics can help promote the production of bacteriocins (bacteria-killing agents) and short-chain fatty acids. They also prevent potential disease-causing bacteria from binding to the cells of your gut lining. Probiotics supplements may significantly reduce your risk of developing infections of the upper respiratory infection tract and reduce flu-like symptoms. (1)
When buying a probiotic, make sure you get one with time-release tablets that wil deliver its bacteria to your gut, like this one.
Vitamin C is an essential micronutrient, potent antioxidant and immune booster. It supports both the innate and adaptive immune systems and has the ability to accumulate in phagocytic cells – such as neutrophils – where it performs many important immune activities.
Vitamin C plays an important role in phagocytosis – helping to remove harmful pathogens and cell debris from your body. It also improves the production and function of B- and T-cells, which are vital for overall immune defences. Taking vitamin C supplements can help in both preventing and treating respiratory and systemic infections. (2)
As an antioxidant, Vitamin C is also essential for neutralizing reactive oxygen species generated by the environment, diet, stress, alcohol, and so on.
Garlic is one of nature’s greatest immune-boosters. Clinical studies show that it contains a potent antifungal agent called ajoene, an organosulfur compound that has been shown to kill off a variety of bacterial, viral and fungal infections.
Ajoene is formed when garlic is chopped or crushed and two other compounds – allicin and allinase – come together. These compounds work alongside garlic’s other powerful antioxidants to fight off infection and enhance the immune system. Research has shown that taking garlic supplements can help to reduce the severity of cold and flu symptoms, as well as reduce the duration of symptoms. (3)
Oregano oil contains several immune-boosting compounds including carvacrol, thymol, and terpinene. Its active ingredient, carvacrol, has been shown to be more powerful antimicrobial than 18 different pharmaceutical drugs.
One study showed that even a small amount of carvacrol was enough to sterilize septic water, kill giardia and treat fungal infections. Oregano’s ability to kill microbes appears to be even more effective than pharmaceutical antibiotics such as streptomycin and penicillin. These properties are extremely beneficial in maintaining optimal immune function.
Oregano oil can also inhibit the growth of clinical strains of serious bacteria such as E. coli and Pseudomonas aeruginosa, even when the bacteria had developed different patterns of resistance. Scientists say this action is due to its carvacrol content. (4)
Our Candida Cleanse formula contains both garlic and oregano leaf extract, as well as 6 other antimicrobial ingredients.
Cod liver oil is a rich source of vitamins A, D, and omega-3 fatty acids, all of which are essential for optimal immune function.
Vitamin A is often referred to as the ‘anti-inflammation’ vitamin because of its important role in reducing inflammation and warding off free radicals that can damage cells.
The vitamin D receptor is expressed on your immune cells and plays a key role in the response of both the innate and adaptive immune systems. Low levels of vitamin D have been linked to autoimmune diseases. Studies have suggested that vitamin D in cod liver oil plays an important part in activating human macrophages in the defence system, helping to ward off serious diseases. (5)
Cod liver oil is also a good source of the omega-3 fatty acids EPA and DHA which harbor powerful anti-inflammatory benefits while also supporting cellular growth and repair.
Zinc plays a role in several aspects of the immune system – inside and out. It’s required for the healing of wounds, and the metabolism of many important vitamins, minerals, carbohydrates and other essential nutrients required for everyday health.
Zinc supports the healthy development and function of your immune cells, including neutrophils and natural killer cells. Those who are deficient in zinc may suffer poor immune function. The development of B lymphocytes and antibody production may also be impaired by low zinc levels.
Some studies have shown that zinc lozenges may reduce the duration of a cold by up around 1-2 days. Zinc supplements may also reduce the number of upper respiratory infections in children. (6)
Zinc also has major roles in basic cellular functions such as DNA replication, RNA transcription, cell division, and cell activation.
Green vegetables are packed with the nutrients your immune cells need to function adequately. Kale, spinach, broccoli, and other greens are rich in vitamin A, vitamin C, folate, and a host of anti-inflammatory antioxidants.
Eating five or more servings of green vegetables a day will help provide your body with important bioactive compounds and vitamins that contribute to healthy immune function.
Almonds are rich in vitamin E, a fat-soluble vitamin that helps in boosting the activity of immune cells and supporting their ability to fend off invading bacteria and viruses.
Just a quarter of a cup of raw almonds provides around 40-50% of your daily recommended intake of vitamin E. Easy to add to a smoothie or salads!
Oranges, lemons, and limes are an excellent source of vitamin C – one of the most important immune nutrients. Foods that contain at least 200 mg of vitamin C per day may help with infection prevention. This is the amount required to ‘saturate’ your cells: any excess vitamin C will be flushed out.
One medium orange contains around 70 mg, a grapefruit almost 90 mg, and a medium raw bell pepper can deliver up to 150 mg. You use sliced red bell pepper to scoop up hummus or guacamole.
These veggies are great sources of beta carotene, a precursor to vitamin A. Beta carotene helps your body to produce white blood cells which are required for fending off bacteria and viruses. It also supports the integrity of mucous membranes lining your respiratory tract, which is a crucial part of your body’s defence system.
A cup of raw carrots provides 100% of your daily recommended intake of vitamin A, while one baked sweet potato packs a whopping 150%!
Selenium is one of the body’s most potent antioxidants, guarding your cells from harmful free radicals that can damage DNA. Selenium also helps in reducing oxidative stress on the body, which in turn reduces inflammation and boosts immunity. Studies have shown that higher levels of selenium result in a greater immune response. On the other hand, low levels of selenium are associated with a delayed immune response.
You only need one to two Brazil nuts a day to get your recommended daily allowance of selenium. Sardines are also a good source: three ounces provides around 80%.
Selenium is also one of the ingredients in our Liver Support formula.
Pumpkin seeds are one of the best food sources of zinc. As mentioned above, zinc is crucial for the healthy development and function of the immune system. If your zinc levels are low, your body can’t produce certain immune cells required for the battle against infection.
Just a quarter cup of pumpkin seeds contains around 20% of your daily zinc needs. Lean meat, shellfish and legumes are also excellent sources.
Turmeric is famous for its powerful medicinal compound, curcumin. Curcumin is responsible for turmeric’s bright orange colour and also its incredible anti-inflammatory properties.
Curcumin is a potent antioxidant and has been shown to boost immune cell activity and enhance antibody responses. When combined with black pepper and healthy fats, curcumin becomes much easier for the body to absorb. It’s great when used as a warming flavoring for soups, stir-fries, stews and even lattes.
Dried tart cherries are not only great for protecting your body from damaging free radicals, they contain high amounts of melatonin: essential for supporting healthy sleep. Sleep is vital for the proper function of the immune system as it’s during rest that your body carries out much of its repair and restoration work.
Tart cherries can be eaten dried or added to baked goods and smoothies.
Fried food, fast food, takeaways – whatever you call it, it certainly won’t help your immune system. Worse, research has shown that fast food may actually increase your risk of developing infections or even chronic disease.
Studies have shown that regular intake of fried food has the potential to reprogram your immune system response, causing it to remain “hyperactive” or in a state of alert. This can cause the immune system to overreact to minor stimuli. (7)
Processed foods are generally anything sold in a packet and contain artificial ingredients or preservatives.
In a study that investigated the effects of Western diet on the immune system, researchers fed mice a diet high in sugar and low in fiber. After a month, the mice showed an acute immune response in which their bodies appeared to be constantly fighting microbial attack. Even after this response was reduced, the mice’ immune systems remained in a reactive mode. This suggests the processed foods can undermine and weaken the immune system.
MSG (monosodium glutamate) is a flavoring additive that enhances the taste of savoury foods. Research suggests regular consumption of MSG can lead to harmful effects to the thymus and spleen. The thymus and spleen both have major roles in the function of the immune system as they create lymphocytes (white blood cells).
A study in which rats were fed a high-MSG diet showed that they ended up with a significant decrease in CD3-positive T-lymphocytes in both the thymus and spleen. MSG harms these important organs by causing serious oxidative stress and interfering with their ability to produce lymphocytes.
It also appears to disrupt the body’s levels of interleukin, the molecule involved in signalling an immune response. (8)
Alcohol destroys some of the beneficial microbes living in your gut, upsetting the balance of healthy and unhealthy bacteria. This can be devastating for your immune defences because your gut microbiome comprises the majority of your immune system.
Alcohol also reduces the efficiency of your digestive system, causing inflammation and lasting damage to the epithelial cells in your intestines. This makes it difficult for your body to absorb nutrients properly.
Additionally, alcohol affects the function of macrophages and reduces levels of immunoglobulin and cytokines, which are required for the immune response.
On top of that, alcohol impairs your body’s production of T cells and B cells, both of which act as first responders to harmful pathogens. (9)
Caffeine triggers the production of the stress hormone cortisol, which is generally only released when your body senses it is facing a threat. Cortisol causes your body to switch to ‘fight or flight’ mode, in which other systems are temporarily shut down so your muscles can run away from the threat.
Although cortisol has anti-inflammatory properties and can help to contain the immune response, chronic elevation can lead to the immune system becoming “resistant”. This occurs when stress hormones accumulate in the body and the increased production of inflammatory cytokines end up compromising your immune response. (9)
Sugar can reduce the function of white blood cells while also increasing inflammatory markers. It’s been found that obese people with a high-sugar diet have fewer white blood cells and a reduced ability to fight infection. (10)
Sugar also has a range of detrimental effects on your hormones, particularly regarding insulin. When you eat or drink large amounts of sugar, your blood sugar increases rapidly. Insulin helps to move that sugar into your blood cells, bringing your blood sugar levels back to normal. However, if your cells become resistant to signals from insulin, you may develop type 2 diabetes, which has ongoing complications for the immune system.
In addition, pathogenic yeasts and bacteria thrive on sugar, which can lead to an imbalance of bacteria in the gut – and further harm to your immune function. Sugar also competes with vitamin C, reducing your body’s ability to absorb it.
Gluten is a protein present in grains such as wheat and barley that triggers the production of a protein called zonulin, which causes an inflammatory reaction in your body. This can lead to a condition called Leaky Gut Syndrome in which the integrity of your intestinal walls becomes more permeable. If toxins and harmful substances pass into the bloodstream, they can provoke an undesirable immune response and further inflammation.
Even people who don’t have an autoimmune response to gluten may suffer from gastrointestinal damage and inflammatory symptoms after eating gluten-containing foods. Ultimately, this may compromise your ability to absorb nutrients and maintain overall health.
Sleep deprivation has long been linked to chronic illness and even premature death. Those who get less than six hours’ sleep a night are four times more likely to catch a cold than those who sleep for more than seven hours. One study found that less sleep may be associated with a higher risk of infectious sickness. (11)
Sleep may be the most important factor in predicting your chance of catching a cold: even more than age, stress levels or cigarette smoking.
Exercise causes the heart to pump faster, which in turn stimulates the lymphatic system. Because the lymphatic system is responsible for removing waste products and toxins from your bloodstream, it also helps to speed up your body’s detoxification pathways. A sluggish lymphatic system can result in a build-up of viruses, bacteria and fungi in your body. (12)
Regular physical activity can also help to activate the pathways that assist with liver detoxification. This allows your body to flush out toxins, waste and other harmful substances more efficiently. When there are fewer toxins in your circulatory system, your microbiome can spend more time fighting off invading pathogens species in your gut.
Exercise can even help to boost the diverse range of beneficial microorganisms in your gut, right where most of your immune cells reside.
Drinking plenty of clean, filtered water each day has been shown to have a beneficial effect on the mucosal lining of your gastrointestinal tract. It’s also essential for helping flush out any toxins that have accumulated in your system, which can be harmful to the balance of good bacteria.
Water also helps keep waste moving through your bowels so that it can be excreted efficiently. Without adequate water, waste can end up spending long periods of time in your intestines, where it is likely to begin fermenting. This becomes a haven for bad bacteria and yeast.
During stress, the immune response is inhibited. Short term suppression of the immune system is not dangerous, but long-term suppression can leave you vulnerable to infection and disease.
When you are stressed, your brain sends defence signals to the endocrine system, which then releases hormones that suppresses your immunity. It’s also been suggested that stress is responsible for as much as 90% of all illnesses and diseases, including cancer and heart disease. This is due to the way stress triggers chemical reactions that reduce white blood cells and NK cells, and increases inflammation.
Your stress response also causes your heart rate and blood pressure to rise, which puts strain on your circulatory system. (13)
Try to take time out to relax and ‘de-stress’ each day. Practise yoga, deep-breathing, or meditation, or simply take a walk.
The best way to prevent infections from pathogens is to stop them from entering the body. Wash hands after using the bathroom, before preparing or eating food, after blowing your nose, coughing, sneezing; touching animals, or when caring for a sick person.
Use plenty of water and soap and rub it over your palms and backs of your hands. Wash for at least 20 seconds before rinsing under running water.
Touching your face can transmit bacteria through your mucous membranes, including your eyes, nose, mouth and ears.
Make an effort to avoid touching your eyes, nose, and mouth without washing your hands first. Use an alcohol-based hand sanitizer if soap and water are not available.
Bacteria and viruses can be spread when an infected person coughs, sneezes, or talks, and droplets from their mouth or nose land in the mouths or noses of other people nearby. Droplets can also be breathed into the lungs.
Social distancing or “physical distancing” is simply a matter of maintaining a space between yourself and other people outside of your home. Practising social distancing means keeping at least 6 feet (2 meters) from other people. If your immune system is weak, consider avoiding groups and staying away from crowded places or mass gatherings.
Cover your mouth and nose with a tissue when you sneeze or cough, then safely dispose of the tissue. Or, if you don’t have a tissue, cough or sneeze into your elbow rather than into your hands. Avoid touching used napkins, tissues, handkerchiefs, or other items used by other people.
Lastly, don't share eating utensils, plates or drinking glasses with others!