|In this fact sheet, we try to answer the following question: what can be done to preserve the vigor of our immune system in order to better guard against infections and maintain good health? It will not be a question here of allergies , or autoimmune diseases (which appear when the immune system makes the mistake of attacking an organ or healthy tissues, as is the case of rheumatoid arthritis and the MS ).|
In biology, immunity refers to the body’s ability to defend itself against threatening substances for its proper functioning or survival. These “threats” can be of 3 orders: microbes (viruses, bacteria, fungi, parasites), cells that have become cancerous or a foreign body (a splinter, as well as a grafted organ).
It has long been known that with age or disease, immunity weakens and the body becomes more vulnerable to infection. These last ones often become more frequent and more serious. A common flu can then degenerates into pneumonia and be fatal.
That said, we also note that some apparently healthy adults with a normal amount of immune cells (according to blood tests) often contract infections such as colds or gastroenteritis. On the contrary, under similar conditions, others are more resistant. The difference would be played out essentially in terms of lifestyle habits. Indeed, many data from epidemiological studies indicate that diet, smoking, sleep, physical activity, the degree of stress, the quality of human relations and the living environment all influence the quality of the response. Immune.
Thus, health and immunity are closely linked: taking care of one’s day-to-day health improves one’s immunity, and vice versa.
The Risk Factors section presents lifestyle habits that weaken immune defenses, and the Preventionsection, those that can strengthen them.
If at some point the body needs an outside boost, various additional solutions can be used. The Medical Treatments and Complementary Approaches sections are the most commonly used.
|What is the immune system for?
It is the immune system that provides a timely fight against common infections, such as colds and flu, but also long battles against cancer . Having a healthy immune system is not only a guarantee of health, but also of life! Without an immune system, a simple scratch would become fatal because the scratch exposes our tissues to a host of microbes naturally present in the air, in the water and on the skin.
Scientists are not very familiar with the characteristics of the “optimal” immune response. However, they know that the immune system is linked, through a complex communication system, with virtually all parts of the body.
To learn more about the components of the immune system (skin, mucous membranes, thymus, spleen, lymphocytes, etc.) and their respective roles, see our text Immune System: What is it? .
Symptoms of weak immune system
The following symptoms may be a sign of a weakened immune system.
- A tired persistent, often hides a chronic stress or lack of sleep, two factors that weaken immunity.
- Increased susceptibility to infections, such as frequent colds, urinary tract infections, herpes outbreaks, recurring vaginitis, persistent wart, etc.
- Of wounds that take time to heal or heal.
People at risk for weak immune system
People affected by immune impairment are:
- People who are weakened by any of the following factors are particularly affected:
– a chronic or serious illness : diabetes, lung disease, cardiovascular disorder, kidney disease, cancer, human immunodeficiency virus (HIV) infection ), etc.
– a treatment : for example, chemotherapy against cancer.
- Older people generally have an immune system that responds less quickly and less to infections than middle-aged adults. Moreover, this explains that vaccination is less effective among them. Their smaller appetite and their less varied diet explain this in part. The thinning of the skin, the drying of the mucous membranes and the slower healing of the wounds also contribute a lot. Indeed, the body envelope is the most important safeguard against infections. Over time, the body also produces fewer white blood cells.
Risk factors of a weak immune system
The risk factors for an immune system are:
- The malnutrition. An unbalanced diet in quantity or quality is the most important cause of immunodeficiency worldwide and makes it vulnerable to many infectious diseases.
- A sedentary lifestyle, and conversely, overtraining.
- The lack of sleep.
- The chronic stress. One of the multiple effects of chronic stress on the body is to reduce the ability of the immune system to respond.
- The exposure to toxins, including the use of chemical household cleaners and herbicides on lawns, and consumption of fruits and vegetables sprayed with insecticides.
- Exposure to outdoor air pollutants as well as those that spread inside homes (mold, bacteria, tobacco and flue gases).
- The overweight and obesity. Immune functions seem injured by excess body fat, according to studies in humans and animals. It has even been observed that obesity increases the risk of contracting certain specific microbes, such as influenza (responsible for influenza) and Helicobacter pylori (associated with peptic ulcers). Hormonal changes and the increased presence of pro-inflammatory substances may be involved.
Prevention of a weak immune system
|Here are the habits of life that, according to current knowledge, provide the best chance of maintaining a strong immune system.|
The major malnutrition (marasmus) deficit in calories and proteins is the main cause of immune deficiency. It is found mainly where poverty and hunger are present.
In industrialized countries, micronutrient deficiency is becoming more common. The popularity of junk food partly explains this phenomenon. This form of malnutrition results from a lack of vitamins and minerals. Animal studies have shown that a deficiency of one of the following micronutrients impairs immune function: zinc, selenium, iron, copper, calcium, folic acid, or vitamins A, B6, C, and E2, 3.
Moderate physical activity
The multiple benefits of regular physical activity are known: better cardiovascular fitness, muscle mass maintenance, blood pressure normalization, weight control and the reduction of several risk factors associated with chronic diseases.
In addition to promoting good overall health, exercise may also have a direct effect on immunity. By improving the blood circulation, exercise would allow the various substances of the immune system to circulate more easily in the body. This good circulation is essential to prevent the infection of a wound, for example. In addition, it has been observed that some immune components are stimulated by physical activity.
In the elderly, some studies indicate that regular physical exercise helps prevent the decline of immune function.
However, it is better to go moderately, because overtraining would cause upper respiratory infections, such as colds and flu.
Without a doubt, stress has a detrimental effect on health if it is present in a constant or prolonged way. Researchers interested in the link between stress and immunity does not focus on one-off, short-term stress, but rather on frequent and constant stress (for example, balancing the demands of work and life). Family or take care of a sick relative). The stress causes the release of stress hormones such as cortisol and adrenaline. These hormones are very useful in the short term, but harmful if they are produced for a long time. They then directly harm the immune defenses by inhibiting the production of cytokines .
Some studies have shown that caregivers of Alzheimer’s patients have higher levels of cortisol and produce fewer antibodies in response to the influenza vaccine. The researchers noted that the effect of this stress on immunity was inversely proportional to the support of the caregivers’ entourage.
To lower the level of stress, it is suggested to identify the situations at the root of the tensions and to look for ways to better confront them (rather than avoid them). Consulting a psychologistor psychotherapist can be a great help. See our report Stress and Anxiety and our Psychotherapies fact sheet.
Other important factors for health and immunity
Basic hygiene measures to prevent contracting or transmitting an infection
See also Prevention of our Diarrhea, Gastroenteritis, Influenza, Genital Herpes, and Cold sores, Urinary Tract Infections, Otitis Media, Colds, Vaginitis and Warts. In addition, visit our Healthy Living section, which brings together concrete information on the most important determinants of health (fitness, sexuality, environment, weight, mental health, etc.).
Medical treatments of weak immune system
The medicine offers various medications to treat an infection or reduce the risk, as appropriate. Here are some examples.
- Antiseptic lotions. They are quickly applied to minor wounds, cuts and scratches. However, prolonged use is not recommended because it can cause strains of bacteria resistant to treatment.
- Antibiotics. Useful for treating bacterial infections or preventing contagion in some cases.
- Vaccination. It is a way to strengthen the immune system and improve the protection of individuals against certain infections. It sets up a specific immune memory. The duration of vaccine efficacy varies depending on the type of vaccine. Consult our Vaccination file: current ideas and debates .
- Antivirals. These drugs that inactivate viruses can be part of the treatment of a viral infection such as shingles or chicken pox in adults. They can also be given to people who are more vulnerable to preventing a viral infection or reducing its consequences, such as flu.
- Medications against parasites, such as antimalarials. It is recommended to take them before traveling to a region of the world where the risk of contracting malaria is high.
Sometimes the doctor chooses to administer antibodies , especially if it is necessary to strengthen the immune system emergency. This method, called serotherapy, provides short-term immunity.
In case of high susceptibility to infections, the doctor can establish whether it is a primary immune deficiency (linked to the genes). In this case the symptoms are more pronounced and visible in childhood, including recurrent infections, serious, long-lasting and difficult to treat. Specific treatments then apply.