Of all the systems in our body, the immune system is perhaps the most easily influenced by everything we eat and do, as it constantly reacts to substances both within and outside our body.
For the most part, it does an incredible job at keeping us healthy – but at some point, it needs our help in supplying it with a sufficient amount of the nutrients that facilitate its functioning.
#1: Vitamins and Minerals.
By directly influencing various functions in our body, the presence or absence of vitamins and minerals (collectively called “micronutrients”) can have a significant impact on our immune function
Let’s start with vitamin C, since its immune-boosting effects have been the focus of more research than perhaps any other nutrient.
At a basic level, vitamin C is required for the proper functioning of our immune system, since it promotes and stimulates its functions. Beyond that, even the activity of our immune cells seems to correlate with our levels of the vitamin – especially when it comes to resisting and effectively destroying pathogens (disease-causing microorganisms). And although vitamin C can’t seem to prevent us from getting a common cold (contrary to popular belief), it does help get rid of one. Studies have also associated lower levels of vitamin C with stress, alcohol-intake, smoking, and the use of antibiotics, painkillers and so on.1
Then there’s vitamin D, which has received nearly as much attention as vitamin C for its effects on our immunty, mostly because it’s required for the multiplication of cells. Maintaining adequate levels of vitamin D would, thus, result in a healthy number of immune cells. Vitamin D also produces compounds and proteins that fight infections, and even facilitates the communication of immune cells with one another – which, amongst other things, stops the immune system from attacking the body’s own healthy tissue.2 Many studies have shown that a vitamin D deficiency can increase the risk of diseases like type-1 diabetes mellitus, multiple sclerosis, psoriasis and rheumatoid arthritis.3
Vitamin A also deserves special mention for a couple reasons. Like vitamin D, it, too, is required for cell division, which helps maintain sufficient quantities of immune cells. It even helps these cells attack harmful substances and pathogens, by enabling them to recognise the unwanted invaders and identify the site of infection.4
The role of other vitamins and minerals –
B-vitamins, zinc, iron and selenium also contribute to cell division and help maintain the population of immune cells.1
Apart from simply being present in adequate numbers, immune cells also have to operate to their fullest potential. The immune system appears to be particularly sensitive to free radicals, which are reactive molecules that damage cells and proteins in excess numbers.5Luckily, the body can keep their numbers in check through its natural antioxidant system, which is made up of vitamins C, E and A.
#2: Probiotics and Prebiotics.
With the upsurge in research being conducted on gut bacteria, the recent years have discovered functions and benefits of the ‘good bacteria’ extending far beyond our gut’s health.
Inhabiting our gut from our birth, these bacteria are instrumental to the development of our immune system. Acting as the “gatekeeper” to our bloodstream, they serve as the first line of defence against pathogens and harmful products in the food we eat, by preventing microbes from sticking to the lining of our gut and even neutralising certain toxins.6-8
Also directly affecting our immunity is their ability to produce some B-vitamins (like B12, biotin and folate), and help the body absorb the iron from the food we eat (vitamins and minerals that we know maintain a healthy number of immune cells).9
It’s important to nurture this inner ecosystem of healthy bacteria by boosting their numbers via probiotics, i.e., foods in which they exist (like yogurt), and prebiotics, i.e., foods that help them thrive (food rich in dietary fibre like whole grains, legumes, dried fruits, seeds, fruits and vegetables).
‘Phytonutrients’ is an umbrella term for various plant compounds that affect the body in a positive way. It’s these compounds that give many fruits, vegetables, herbs and spices their immunity-boosting properties.
There are several classes of phytonutrients (some which you may have already heard of), and many other compounds that don’t fall under a specific class. Let’s take a look at a few of these that particularly stand out when it comes to our immunity.
These are found in red, orange and green foods like tomatoes, carrots and green vegetables.
Other than neutralising free radicals due to their antioxidant properties, carotenoids also affect the production of certain antibodies and cells. A carotenoid called ‘beta-carotene’ is converted into vitamin A in the body, which, as we’ve seen, is required for almost every aspect of immune cell division and maintenance.10
Our main dietary source of resveratrol is from grapes and wine. This phytonutrient is believed to increase the survival and stress-resistance of cells from factors such as free-radical damage, and build our immunity at a cellular level.3
Sulphur compounds in garlic –
These increase the production of enzymes that detoxify the body. Some evidence even suggests that garlic can enhance the way our body uses iron.11-13
Compounds in ginger –
These relieve the symptoms of a cold, also helping with asthma. Certain compounds in ginger have even been shown to be effective against the flu virus and respiratory infections.14-18
#4: Healthy Fats.
Immune cells rely heavily on cell-to-cell communication.5
Many fatty acids are required in order to build the structure of immune cells. Structural changes govern how these cells interact, what they can interact with, and how nutrients are transported to them. All these factors can affect how we respond to pathogens.
Different types of fatty acids also have their own, specific roles.
Omega-3 Fatty Acids –
Both omega-3 and omega-6 fatty acids regulate our immune system, but our intake of them needs to be in a balanced ratio. We already get enough omega-6 in our diet, so we probably need to increase our intake of omega-3 fatty acids (through sources like fish oil, flaxseed oil, or marine algae), because –
- They help reduce chronic inflammation, an underlying cause of many lifestyle diseases like diabetes and heart disease
- They also seem to boost the activity of immune cells, especially when it comes to the respiratory and gastrointestinal tracts19
Coconut Oil –
Its high amount of immune-boosting fatty acids called ‘lauric acid’ makes coconut oil unique amongst others.
Lauric acid has extremely powerful antibiotic, antiviral, and antifungal properties. Interestingly, lauric acid is even found in mother’s breast milk, providing the newborn with antimicrobial protection.
Keep in mind, though, that coconut oil is still a saturated fat, so its consumption should be limited.
Ghee has a saturated fat called butyrate, which helps our intestine function properly and prevents diseases of the digestive tract (like ulcerative colitis and Crohn’s disease). Butyrate is also produced by some of the good bacteria in our gut.
Ghee has even been shown to increase the availability of enzymes that help the liver detoxify the body.20, 21
Coconut oil and ghee are highly resistant to heat, making both ideal for cooking.
1] Exercise regularly – doing so improves our cardiovascular health, lowers blood pressure, and helps control our body weight, all of which affect our immunity. Exercising may even directly contribute to better immunity by promoting good circulation, which allows immune cells to do their job efficiently. It has also been associated with an increased amount of antibodies, the proteins that neutralise pathogens.22
2] Get sufficient sleep – inadequate sleep disrupts the immune system and leads to chronic inflammation.23
3] Drink less alcohol – alcohol diminishes the availability of many nutrients that play a key role in immunity.
4] Try not to stress – the immune system is directly impaired by stress, which disrupts communication between the nervous system, the endocrine (hormonal) system, and the immune system.
Our immune status is a sensitive indicator of the supply of nutrients in the body and the healthiness of our lifestyle. These simple measures go a long way in helping us take care of this intricately designed system.
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