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The Immune System Explained

The immune system is a host defence system made up of many biological structures and processes within your organism, that protects against disease. To function properly, the immune system detects viruses and bacteria in the body and distinguishes them from the body’s own healthy tissues. If your immune system is compromised, the first response the body has is to repel the virus or bacteria, through bodily functions such as coughing, sneezing, or sweating. If you have a cut, for example, the body’s response is to cause inflammation as a first response. Inflammation can show up as redness, swelling, feelings of heat or pain in an area of the body, which are caused by increased blood flow to the affected tissue.

The immune system is affected by many factors, including sleep and rest, stress levels, nutrition and diet, to name a few. Looking after the body and protecting it from picking up a virus is essential, however it isn’t always possible to live in a bubble, therefore boosting the immune system is key to protecting ourselves, should illness arise.

There are many ways in which to boost the immune system, and keep it as strong and healthy as possible. First, let’s analyze the biggest culprits for negative effects on the immune system:


Resting, napping, sleeping, are probably the best ways to help boost the immune system. Resting gives your body a break, and allows it to focus on healing. This is the primary reason why someone who has had an accident is put on strict bedrest, or why a person with a severe injury is sometimes even put on a forced coma. Sleeping causes your blood pressure to drop, and your heart-beat lowered. It releases hormones that slow breathing down, relaxes the muscles throughout the body, and reduces inflammation to assist with healing.

According to the National Sleep Foundation in the United States, deep sleep is very important for acquiring the necessary energy for healing the body. NREM (non-rapid eye movement) sleep occurs first in a few stages, and it grows in progression to be the deepest, and most restorative sleep. This is when your blood pressure drops, breathing becomes slower, muscles relax as blood supply to muscles increases, tissue growth and repair occurs, and energy is restored. It’s also when growth hormones and repair are released, essentially when babies do their biggest ‘growth spurts’.

REM sleep (rapid eye movement), first occurs about 90 minutes after falling asleep, and after NREM, and recurs about every 90 minutes, getting longer later in the night. REM provides energy to the brain and body, and when the body becomes immobile and relaxed as muscles are turned off. It’s also when the brain is active and dreams occur, the eyes dart back and forth, and when the body supports daytime performance.

Proper sleep can also affect body weight, as sleep helps balance the appetite by helping us to regulate hormone levels; when we are sleep deprived, we may feel the need to eat more. The Foundation also recommends making up bad night-time sleep with a 20-minute nap, or two naps of no more than 30 minutes each.


For most of us, stress is a natural part of life that can last for a few minutes, like when you wake up late for an appointment, to years, like when you’re looking after an ill loved one. Although stress can be a great motivator to getting things done, and it can provide cortisol in short bursts to boost immune system, it can also take a toll on your health by decreasing the body’s lymphocytes, our helpful white blood cells that help fight off infection. In basic terms, the lower the lymphocyte levels in the body, the more at risk we are for viruses and disease.

According to the National Institute of Health, stress is responsible for as much as 90% of all illnesses and disease, which happens when stress triggers a chemical reaction in the body that decreases white blood cells and NK cells (those which can even kill off nasty cancer cells).


According to the US National Institute of Health, malnutrition is the most common cause of immune deficiencies worldwide, while over-nutrition and obesity also reduce immunity. In the elderly, one of the most recognized consequences of aging is a decline in immune function, and it’s believed this is largely due to a slowing down of cellular reproduction, lack of regular exercise, as well as a deficiency in nutrient intake. According to studies by Harvard Medical School, there is an evident connection between micronutrient malnutrition and sustained health. Micronutrients are one of the major groups of nutrients your body needs, and includes vitamins and minerals, necessary for energy production, immune function, blood clotting, bone health, fluid balance, and more. Studies further indicate that older people tend to eat less and often have less variety in their diets, requiring more supplementation.

Scientists have long recognized that people who live in poverty and are malnourished, are more vulnerable to infectious diseases. Harvard Medical School studies further indicate that deficiencies in zinc, selenium, iron, copper, folic acid, and vitamins A, B6, C, and E, can have altering effects on the immune system and its response.


Regular exercise is one of the most important keys in boosting the immune system – it helps maintain healthy blood pressure, improves cardiovascular health, helps control body weight, which all help ward off a variety of diseases. Exercise promotes good circulation, which allows the various cells and substances of the immune system to move through the body freely and do their job efficiently.

It’s important to note that studies have indicated that strenuous exercise has also been shown to temporarily depress the immune system, and exercising while feeling ill has been shown to make the symptoms and severity of the illness, even worse.

Jeffrey A. Woods, a professor of kinesiology and community health at the University of Illinois, says that in general, moderate exercise, such as a leisurely jog or walk, can prop up the immune response and lessen the duration and severity of a mild infection. He further recommends that “if you don’t feel well, especially if you have fever or body aches, daily exercise should be stopped until you have recovered.” He adds that it’s okay to exercise if you have a simple head cold or congestion, but it’s best to avoid heavy, prolonged exercise while feeling ill.”


There are many lifestyle and dietary changes we can do in order to support our immune system from the inside out. The body is an incredible machine, able to fight off infection, but we need to do our part in order to help it do its job.

Everything you put into your body – from food, drink, to stress, fresh air, and sleep deprivation, make up the ingredients that your body will use to create new cells, muscles, bone, tissue, and so on. Especially when there exists a lowered immune system, or by natural effects of aging, the body is resilient and can heal from many illnesses – current ones and ones yet to be discovered.

Here are the most important compilation of specialists’ recommendations, to help boost your immune system and protect it from illness:

Eliminate sugar intake altogether.

No more ice cream, cookies, muffins, sugary drinks (including juice) and cereals. Honey and maple syrup may be consumed in small amounts to flavour teas, etc. Sugar puts your white blood cells into a ‘temporary coma’ for as much as 3 hours, with as little as 1 teaspoon (4.5 grams) of sugar. Instead, eat real foods, as fresh as possible (or frozen as second best); you shouldn’t need anything with a nutritional label on the side, as this means it’s a processed food.

Avoid dairy foods.

As you work to strengthen your immune system, skip the milk and cheeses, ice cream, whey, sour cream, and heavy creams, as these foods can increase your body’s production of phlegm and mucous, which are a breeding ground for germs to live optimally in your gut. You may consume a small amount of butter, ghee, and plain yogourt (no sugar or sweeteners added). Instead, if you need a dairy-alternative to cook your meals with, try using unsweetened organic almond or hemp milk as better options.

Boost your veg intake

Vegetables are loaded with micronutrients your body needs to function at its best. Ensure each meal has at least 50% vegetables (fresh, or lightly steamed), and if possible, drink your vegetables as well. Making a daily batch of freshly blended vegetables, such as carrots, cucumber, kale, is a powerful way to boost your immune system. (note: a little fresh juice in a blender goes a long way! Just a few ounces will do your body wonders).