Winter is Cold Season. We spend more time indoors, and the transition between warm temperatures indoors and cold temperatures outdoors challenges our immune system. This is when viruses and bacteria often have an advantage.
That’s why it is important to pay attention to a strong immune system. By maintaining a healthy lifestyle, you can also benefit your immune system.
Below are some tips on how you can strengthen your immune system:

1. avoid stress
Stress is not only a common trigger for symptoms of atopic dermatitis. Long-term stress can also weaken the immune system. When we are stressed, our body releases stress hormones like cortisol. This leads to increased production of inflammatory mediators through various pathways in the body. Prolonged stress and elevated cortisol levels can have numerous consequences for the body.
Stress cannot always be completely avoided. That’s why it’s important to pay attention to regular breaks and to take time for relaxation. For example, meditation and mindfulness exercises are suitable for this purpose. Practiced regularly, they can improve stress management and are also easy to learn.
2. sufficient sleep
Adequate sleep contributes to a well-functioning immune system. While we sleep, the body undergoes repair processes. For example, the function of certain defense cells, the T-cells, is strengthened. These cells attach to infected cells and fight them off. Additionally, the concentration of other immune cells is affected by lack of sleep. Those who regularly sleep too little are more susceptible to colds and other viruses. Therefore, getting enough sleep is crucial for strengthening the immune system in winter.
3. regular exercise
Regular exercise keeps the body fit and is good for the mind. Even moderate activity has a positive effect on the immune system and stimulates the production of certain immune cells. The concentration of natural killer cells increases, and the number of antibodies responsible for fighting pathogens also rises. Studies show a lower rate of respiratory infections in people who regularly engage in endurance sports. Suitable sports include cycling, running, or swimming. Even though it may be challenging in cold and dark conditions, exercise and physical training are worthwhile even in winter.
Tip:
When you sweat during exercise, it’s easy to get cold after the workout. It’s best to remove sweaty clothing quickly and wash the sweat off your skin with a short, not too hot shower. Don’t forget to moisturize afterwards.
4. soak up the sun and daylight
Ideally, physical activity takes place outdoors. Even when the days are shorter in winter and the sun is rarely seen, exposure to daylight is important. Our internal clock needs daylight to regulate bodily functions according to the time of day and to regulate hormone levels. For example, a lack of light can disrupt the production of the sleep hormone melatonin, leading to fatigue and lethargy. Additionally, exposure to daylight increases the production of the mood enhancer serotonin. Therefore, even on cloudy winter days, a walk outdoors can benefit both the body and the soul.

Important:
Excessive sun exposure can lead to skin damage, including skin cancer. Therefore, time spent in sunlight should always be limited and accompanied by appropriate protection.
5. ensure adequate vitamin D intake
Sunlight is our main source of vitamin D. Even with a healthy and varied diet, only 10-20% of the body’s vitamin D requirement is obtained from food. The remainder is produced by the body with the help of sunlight. Although a sufficient store of vitamin D can be built up during the summer months, a deficiency can occur more quickly, especially in winter. This can be determined through a blood test. If vitamin D levels are too low, the intake of vitamin D supplements can be considered in consultation with a doctor.
6. varied diet
A healthy, varied diet rich in fresh fruits and vegetables provides the body with important nutrients it needs for a strong immune system. For example, adequate intake of minerals such as zinc, iron, or selenium supports the body in fighting off bacteria and viruses. With a balanced diet, the use of dietary supplements is usually not necessary. In fact, taking such supplements prematurely can potentially be harmful to health, especially for children. Therefore, it’s advisable to discuss such decisions with a doctor beforehand.

7. adequate hydration
Water is essential for the body. Sufficient fluid intake is also necessary for a functioning immune system. When we drink too little, the mucous membranes in the respiratory tract, nose, and eyes dry out. This makes it easier for viruses and bacteria to enter the body and trigger infections. Moist mucous membranes, on the other hand, can better eliminate pathogens. The recommendation from the German Nutrition Society is that adults should drink an average of about 1.5 liters of water per day. During hot weather, physical activity, or in cases of diarrhea, this amount may increase. The best options are tap water, mineral water, or unsweetened herbal and fruit teas.
8. alternating showers
There is evidence to suggest that alternating hot and cold showers can strengthen the immune system and reduce the risk of colds. The effect could be related to improved blood circulation due to the alternating cold and warm stimuli. When exposed to cold, blood vessels contract and are less perfused. In contrast, when exposed to warmth, they dilate, and blood flow increases. If the skin is well perfused, this usually applies to the mucous membranes as well. Therefore, well-perfused mucous membranes are important for defense against pathogens.
Tip:
Another advantage of cold water is that it lessens the impact on the skin’s natural acid mantle compared to hot water. In the case of already dry skin such as in atopic dermatitis, the water should ideally not be warmer than 34°C.
Sources:
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