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We tend to think about immunity only when our health begins to fail, while in fact preventive measures should be taken much earlier. The immune system and its ability to protect against disease are influenced by sleep quality, diet composition, taking care of physical activity, psychological balance and preventive health checks. These are the key pillars that enable the body to defend itself effectively against threats and reduce health risks.
What is immunity and what does it depend on?
Immunity is shaped by many factors. The functioning of the immune (immunological) system is linked to all the body’s systems. Its main task is to recognise and neutralise pathogens and to respond to damaged or improperly functioning cells
The immune system is a network of tissues, cells and organs that work together. It includes, among other things, antibodies, leukocytes (white blood cells) and numerous signalling substances that enable communication between cells. This enables the body to respond quickly to threats and pathogens, but also “remember” them and effectively combat them in the future.
The immune system works continuously. Every day it comes into contact with potential pathogens present in the air, food or on the surface of the skin. Most of these threats go unnoticed precisely because of its effective action.
The body’s immunity depends, among other things, on genetics, age, lifestyle, diet, stress levels and sleep quality. Disturbances in the immune system balance can lead both to increased susceptibility to infections and to excessive defensive reactions observed, for example, in allergies or increasingly frequently diagnosed autoimmune diseases.
We have a real influence over many factors affecting immunity. An appropriate lifestyle can significantly support the proper functioning of the immune system. Below are the most important pillars of immunity and practical tips on how to take care of them.
Pillar 1: Nutrition
Proper nutrition is one of the main pillars of taking care of immunity. The diet should be nourishing and meet the body’s requirements for all essential nutrients. In addition, it is worth including dietary “immune boosters”. Below are the most important practical nutritional principles for supporting the immune system:
• Adequate energy intake. Cells need energy to respond effectively to threats, and increased activity of the immune system, for example during infection, further increases energy requirements. A diet with an appropriate energy intake (neither too low nor too high) ensures the smooth functioning of immune processes. When immunity is weakened, it is better to avoid weight-loss diets. Significant caloric surpluses are also unfavourable.
• Adequate protein intake. Amino acids derived from protein are essential for the synthesis of high-quality immune proteins. The minimum daily protein intake is approximately 1 g per 1 kg of body weight. The optimal daily protein intake also depends on factors such as age and physical activity.
• A diet rich in antioxidants. Antioxidants are found, for example, in vegetables, fruit, cereals, nuts, infusions and teas, spices, and more generally in unprocessed food. They are necessary to support antioxidant defence mechanisms that limit tissue damage.
• Key minerals (e.g. iron, zinc, magnesium). These minerals are essential for the production of immune cells. They are found in meat, eggs, fish, nuts, fruit and vegetables.
• A diet rich in vitamin D or its supplementation. An adequate supply of vitamin D regulates the immune system and can alleviate inflammation. Supplement according to recommendations, at a dose of 1,000–2,000 IU of vitamin D from October to May, or throughout the year if you do not get at least 15 minutes of sun exposure per day in the remaining months.
• Omega-3 fatty acids. They protect the body against systemic inflammation, which weakens the body's immune response. Foods rich in omega-3 fatty acids include oily sea fish (such as salmon, mackerel and halibut), flaxseed and walnuts.
• Fibre-rich products that support the gut microbiome. These include, for example, whole-grain cereals (oat flakes, groats, wholemeal flour products), fruit and vegetables. Fibre influences the diversity of the gut microflora, which actively supports the immune system.
• Probiotic ingredients. Natural fermented foods, such as kefir, kombucha or fermented vegetables, can positively influence the gut environment and support microbiome health.
A diet that supports a healthy immune system is not based on a few selected products with beneficial effects, but on the overall composition of the diet, which must provide all essential nutrients. The typical Western dietary pattern, based on processed foods, is associated with a risk of developing chronic systemic inflammation, which weakens the immune system.
Pillar 2: Sleep and recovery
Sleep is one of the most important pillars for the proper functioning of the immune system. During sleep, the body regenerates most intensively, immune system cells are organised, and defence mechanisms are strengthened. Research clearly shows that both short-term and chronic sleep deprivation disrupt immune balance and predispose individuals to increased inflammation and a reduced ability to fight infections.
People struggling with sleep deprivation show changes in the activity of key immune cells, as well as elevated levels of inflammatory markers such as interleukin-6 and C-reactive protein. During sleep, melatonin, known as the sleep hormone, is released. In addition to regulating the circadian rhythm, it also has antioxidant and anti-inflammatory properties.
Regular, sufficiently long sleep supports an efficient immune response, shortens recovery time and may reduce the risk of a severe course of infection. Below are some of the most important recommendations:
• Sleep duration. Most adults need 7–9 hours of sleep per day, with women requiring around 20 minutes more than men.
• Sleep quality. Interrupted, shallow or restless sleep does not ensure full recovery, even if its duration is theoretically sufficient. Research confirms that a deficiency of REM sleep leads to disturbances in immune cell production and abnormal levels of pro-inflammatory cytokines. You can support sleep quality by choosing a calm, darkened and well-ventilated environment. Fall asleep without distractions, limit caffeine intake in the evening and try to avoid exposure to blue light before sleep.
• Regularity of the circadian rhythm. Going to bed and getting up at similar times supports proper melatonin secretion and the synchronisation of immune processes. Irregular sleep, for example among people working shifts, is associated with increased susceptibility to infections.
Pillar 3: Movement
Physical activity supports the circulation of immune cells in the body, improves communication between them and helps maintain a balance between protective responses and undesirable inflammation. Movement is a natural regulator of immune processes. People who engage in regular physical activity tend to show a stronger immune response and a lower risk of developing chronic inflammation.
Physical activity, such as brisk walking, cycling or swimming, temporarily increases the number of immune cells circulating in the body, which improves the body’s ability to detect and eliminate pathogens at an earlier stage. Regular activity also helps reduce stress levels and pro-inflammatory cytokines, and improves insulin sensitivity and cardiovascular health, which indirectly contributes to better immune function. 150 minutes of physical activity per week is the minimum required to stay healthy. Particularly valuable is activity undertaken outdoors, which helps to condition the body, supports oxygenation and helps regulate the biological clock.
It is worth mentioning that while moderate physical activity supports immunity, excessive exertion without properly planned recovery can have the opposite effect and place strain on the body. A demanding training plan without adequate recovery periods, or intense exercise performed in a fasted state, can increase cortisol and adrenaline levels and reduce immune cell activity. Balance is key – both lack of movement and training overload are not good for health.
Pillar 4: Stress avoidance and mental health balance
Stress and mental well-being have a significant impact on the condition of the immune system. Although short-term stress can mobilise the body to act and fight infections, chronic psychological stress leads to dysregulation of immune mechanisms.
Research shows that people experiencing prolonged stress, low mood or anxiety disorders are more susceptible to infections and recover more slowly. Importantly, stress affects immunity not only directly but also indirectly – it worsens sleep quality, promotes unhealthy eating habits and limits spontaneous physical activity, creating a “vicious circle”.
One interesting phenomenon that vividly links stress with immunity and mental health is “leisure sickness”. This term refers to a situation in which symptoms of infection, such as a cold, headache, weakness or a low-grade fever, appear when chronic stress suddenly subsides. This often occurs during holidays.
The mechanism behind this phenomenon is explained by a sudden change in the regulation of the nervous and endocrine systems. During chronic stress, the body functions in a state of “mobilisation”, and the immune system is modulated by elevated levels of cortisol and adrenaline. A rapid reduction in tension can lead to a “dysregulation” of the immune response, revealing previously suppressed infections.
In such situations, the solution is to develop methods for reducing tension and regulating stress, including relaxing physical activity, breathing exercises and changes in your routine. Prolonged functioning under excessive strain has an adverse effect on the body.
Pillar 5: Preventive health checks
Preventive examinations play an extremely important role in maintaining proper immune function. Early detection of abnormalities allows for faster intervention and helps prevent long-term negative health consequences. Any worrying symptoms should be discussed with healthcare professionals. Most people should regularly undergo blood tests, including a full blood count, assessment of iron levels and inflammatory markers, as well as a dental check-up. Make sure to have regular preventive examinations as recommended by your doctor.
References:
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