Summary
The change in season and the incoming cold weather are factors that destabilize and weaken our immunity which makes our bodies more vulnerable and more exposed to infections. To strengthen your immune system effectively and start off the winter season the right way, find out what defense strategies our immune system uses and which nutrients are needed for it to function properly.
What exactly is the immune system ?
To protect ourselves from infections and other disturbances our body may encounter, we are endowed with a natural defense mechanism called the immune system. Its main mission is to maintain the body's overall well-being by protecting it from anything that might be harmful to us from the outside. Our immune system is very complex and unique to each and every one of us. It is designed to tolerate foreign agents that are beneficial to our body (such as good bacteria) and to eliminate those that are harmful to it.
Our environment is full of a host of microorganisms and pathogens that try to infiltrate our bodies in order to develop and reproduce. We have two main lines of defense to efficiently protect ourselves from these infectious agents:
- Our body's external barriers, specifically the skin, mucous membranes (digestive, sexual, respiratory) and their associated secretions (saliva, sebum, sweat, mucus, etc.). This first defense barrier against external assaults is designed to prevent pathogens from penetrating into our inner body.
- When external pathogens manage to penetrate the body's first defense despite our natural barriers, we have a second line of defense: internal protectors. These protecters are made up of an "army of soldiers" composed of a large number of cells and specialized molecules that neutralize pathogens that have successfully made their way through our natural barriers.
How to strengthen your immune system
An efficient immune system will be more likely to efficiently fight a virus than a deficient one. We can build a more efficient immune system because we ourselves hold the key to reinforcing our own immune system.
Our intentions play an important role in our immunity
The intestines are fundamental to digestion and especially in absorbing nutrients, but that's not all! It plays a key role regarding our immunity on 3 levels:
- The intestinal lining: a mucous membrane that lines the walls of the intestines, whose role is to let nutrients pass through. It acts as a "filter" that stops pathogens from entering.
- Intestinal microbiota: it is made up of non-pathogenic bacteria that protect the intestines. These bacteria are what prevent pathogenic bacteria from entering the bloodstream or proliferating in the intestines or throughout the rest of our body.
- Intestinal immune system: More than 60% of our immune cells are concentrated in the intestines. These cells defend the body from any agressors to our body and are also involved in tolerating the food we eat.
Poorly managed stress, poor nutrition, or repeated use of antibiotics can disrupt the balance (called symbiosis) of the intestinal ecosystem and weaken our immune system. Eating probiotics (lactic ferments) can help restore this balance. Probiotics are bacteria that, in sufficient quantities, have a beneficial effect on our intestinal microbiota. They can be found in fermented foods (yogurt, kefir, miso, kimchi, kombucha) or in the form of food supplements.
For these bacteria to thrive, it is important to supply them with a favorable environment and especially something to "feed on". These "good bacteria" feed on substances called "prebiotics". They are essentially dietary fibers found in our food, especially in garlic, asparagus, carrots, onions, leeks, radishes, tomatoes...
A diet rich in nutrients to support a healthy immune system
Covering our nutritional needs in vitamins, minerals and trace elements is key to ensuring that our natural defenses function properly. Some of them have a direct influence on our immune system such as vitamin C, vitamin D and zinc. A deficiency of these vitamins can lead to a disturbance in our immune response.Vitamin C and zinc contribute to our body's defense system by shielding it from oxidative stress generated by pathogens. Vitamin C and zinc are powerful antioxidants that help fight free radicals, support the immune system, and limit white blood cell (immune cell) oxidation. Also, vitamin D tends to be scarce in winter and plays a crucial role as it is also involved in our immune response.
Plants that sustain our immunity
Certain plants such as Echinacea have proven themselves to be effective and are frequently used in the preventing and treating of certain winter infections such as the common cold. Studies have shown that Echinacea's immuno-stimulant, anti-inflammatory and antibacterial properties are likely to strengthen our immune system.
Getting a good night’s sleep
Sleep is very important for the body : it plays a role in our memory, concentration, and directly influences our mood. It also plays a key role in regulating our biological clock and hormonal system. Many studies have also shown that a lack of sleep as a result of repeated bouts of insomnia has a negative impact on our immune system because it decreases the activity of certain white blood cells and how antibodies synthesize. Getting a restful 7 to 9 hours of sleep per night is the key to making sure our immune system works properly and limits the risks of infection, especially in winter.
Reducing stress
Chronic stress, like lack of sleep, strongly disrupts how our immune system functions. The huge production of adrenaline and cortisol induced by chronic stress leads to severe malfunctions in our immune system, especially with our white blood cells (immune cells). As such, fighting against stress is a vital step in strengthening our immune system.
Abstain from harmful substances
Certain substances such as tobacco and alcohol can lead to an immune deficiency because they cause an accumulation of free radicals and toxins that alter how our cells function properly. A decrease in immunity leads to an increased risk of infection. Adopting a healthy lifestyle by reducing chronic tobacco and alcohol consumption helps to strengthen our immune system, especially at a time when it is most in demand.
Important points to remember
A healthy lifestyle combined with dietary supplements to strengthen your immune system can help you cope with winter ailments and improve your body's resistance.
Bibliographic sources
Dimitrov S, Lange T, Gouttefangeas C, et al. Gαs-coupled receptor signaling and sleep regulate integrin activation of human antigen-specific T cells. J Exp Med. 2019;216(3):517-526. doi:10.1084/jem.20181169
Maywald, M., Wessels, I., & Rink, L. (2017). Zinc Signals and Immunity. International journal of molecular sciences, 18(10), 2222.
Liugan, M. et Carr, AC (2019). Vitamine C et fonction neutrophile: résultats d'essais contrôlés randomisés. Nutriments , 11 (9), 2102.
Baeke, F., Takiishi, T., Korf, H., Gysemans, C., & Mathieu, C. (2010). Vitamin D: modulator of the immune system. Current opinion in pharmacology, 10(4), 482–496.
