Every day we are exposed to a wide range of potentially harmful microorganisms, such as colds, flu and even COVID. But our immune system – a network of complex pathways within our body – helps protect us against these microorganisms and other potential diseases. Essentially, it recognizes foreign invaders, such as viruses and bacteria, and takes immediate action to defend us.
Humans have two types of immunity: innate and adaptive. innate immunity is the body’s first line of defense, consisting primarily of physical barriers (such as the skin) and secretions, including mucus, stomach acid, and enzymes in saliva and sweat that keep microorganisms to enter the body. It also consists of cells that attack any foreign invaders entering the body.
Adaptive immunity is a system that learns to recognize a pathogen. It is regulated by cells and organs in our body such as the spleen, thymus, bone marrow and lymph nodes. When a foreign substance enters the body, these cells and organs create antibodies and multiply immune cells specific to this harmful substance in order to attack and destroy it. They also remember the pathogen for future reference.
There are many things we can do to support our immune system and even improve its functioning. Simple changes to your diet and lifestyle can all play an important role in helping you avoid getting sick.
We are what we eat
The nutrients we get from the foods in our diet play a key role in building and maintaining our immune system.
Take for example the amino acid arginine. This is essential for generating nitric oxide in immune cells, which is an important defense molecule against organisms. Vitamin A and zinc are crucial in the rapid reproduction of immune cells. Vitamin C contributes to the immune defense by supporting the cellular functions of both immune systems. In the same way, Vitamin E It has been shown to enhance immune responses in animals and humans and to provide protection against several infectious diseases, such as influenza, COVID and the common cold.
A varied diet that includes fruits and vegetables, whole grains, nuts, seeds, dairy products, as well as fish, meat or plant protein alternatives, will contain all of these key nutrients that support our immune health.
The vast combination of microorganisms that live in our gut – known as our microbiome – also have significant effects on our health and well-being, despite their small size. In fact, the microbiome is often referred to as the “second brain” due to the extensive relationship it has with the organs and systems of the body.
A particular role that microbes play in our gut is to support immune function. They help control inflammation, the process used by the immune system to protect us from harmful pathogens. Ensuring the microbiome is healthy can improve immune function.
There are many ways to support our microbiome through the foods we eat. For example, research has shown a Mediterranean dietwhich is rich in vitamins, minerals and dietary fiber, has an anti-inflammatory effect in the gut, which can help boost the body’s immune function.
This effect can be explained by a strain of bacteria known as Faecalibacterium prausnitzii Which one is key to immune regulation. This bacterium tends to be low in the Western diet but abundant in the Mediterranean diet. You should also avoid too many refined grains, sugars and animal fats, all of which can increase inflammation in the body, which weakens the immune response.
Probiotics (additional mixtures of live bacteria) may also have benefits. Research has even shown a probiotic mix of bacterial strains Lactiplantibacillus plantarumand and Pediococcus acidilactici reduces the amount of virus detected in the nose and lungs, as well as duration of symptoms, in COVID patients.
Live a healthy life
Your lifestyle can also have a big effect on immune function.
For example, smoking affects both innate and adaptive immunity, causing it to both overreact to pathogens and lower its immune defenses. Alcohol has also been shown to increase sensitivity to bacterial and viral infections. It does this by altering the way our immune system defends itself against infection. Even moderate drinkers may have weaker immunity.
Sleep is also crucial for maintaining immune function. Studies show that frequent, poor quality sleep causes inflammation in the body. It can worsen the immune response, increased risk of infection and worsening infections. Teenagers who sleep only about six hours are also more likely to suffer from common illnesses, such as colds, flu and gastroenteritis.
Stress is another factor known to have a big impact on the immune system. It’s not just chronic stress that weakens the immune system, even brief periods of stress (like an exam) can worsen immune function. Fortunately, mindfulness meditation (which can help manage stress) can be beneficial for the immune system – even if we don’t quite know why yet.
Exercise has also been shown to affect immune function, with research showing moderate-intensity physical activity in particular (such as a brisk walk or ballroom dancing) can improve the immune response. However, getting the balance right is important because long, intense exercise without enough rest between workouts can actually worsen immune function and make you more susceptible to catching an infection. And according to some data, this decrease can occur after only 90 minutes moderate to vigorous intensity physical activity.
Sure, vaccination remains the best way to prevent infection from many common illnesses, such as the flu. But a good diet and a good lifestyle – alongside other preventive measureslike washing your hands or wearing a face mask – help support your immune system and the effectiveness of vaccines.