Strengthening your immune system naturally: The best tips

The function of the immune system is to protect our body from diseases of all kinds and to defend it against harmful pathogens. That's why people like to compare it to a fighting force. However, it is more like a perfectly organised company: Every employee knows his job and knows exactly what needs to be done. Everyone works hand in hand in an optimally coordinated team - and in the vast majority of all cases the problem that has arisen is solved within the shortest possible time.

The employees belong to two groups, the innate and the acquired immune system. They work with cellular and humoral defence mechanisms. Cells are, for example, the phagocytes (macrophages), which eliminate attackers, especially antibodies. Humoral defence refers to body fluids (e.g. blood, lymph) and their constituents. The cellular and humoral immune systems are divided into a specific and a non-specific part. You can find out more here.

1. You often have a cold
   Two or three colds a year, which clear up after about ten days, is normal for adults. But if you are constantly sniffling and coughing, if one infection follows another, if a cold does not get better even after two weeks, then something is not right. Your immune system can't keep up.
   
   
2. You suffer from other infections several times a year
   Also a warning sign: Not only do you often catch a cold, other complaints are also troubling you: for example, infections of the paranasal sinuses and / or ears, inflamed gums, urinary tract infections or fungal diseases. Or you have more severe infections, such as pneumonia, or more than two conditions that need antibiotic treatment.
   
   
3. You often have digestive problems
   A large part of our body's defence system is located in the digestive tract. The "good" bacteria that live in your gut protect you from infections and inflammation. If you suffer from frequent bloating, diarrhoea or constipation, it may be a sign that your immune system is compromised.
   
   
4. Injuries heal slowly
   The healing of wounds is also dependent on the immune system. If you get a scrape, a cut, a burn, your body goes into defence mode. The injured skin, through which pathogens could penetrate, must be replaced as soon as possible by a new layer of skin. The immune cells help with this. So when wounds heal slowly, it's a sign that the immune system is not doing well.
   
   
5. Your stress level is high
   Stress over a long period of time weakens the immune system; the number of white blood cells that fight infections decreases. It is no coincidence that people often get sick after a difficult period at work or after crises in the emotional sphere – often these stressful times are also associated with a lack of exercise and worsening sleep.
   
   
6. You always feel tired and worn out
   Tired, although you actually sleep enough? Lacking energy and exhausted? This can also be a sign the immune system is weakened. However, it is often not easy to identify what really triggers an immune deficiency. There could be other diseases behind it, in particular viral infections, autoimmune diseases such as diabetes, thyroid dysfunction or celiac disease (gluten intolerance) or simply increasing age. There are also things in our own behaviour that weaken the immune system. Be sure to discuss any suspected immune deficiency first with your primary care physician. In addition, there are clinical immunologists who specialize in this kind of thing.

There is still a lot we do not know about the immune defence system, as its functions are so multifaceted and intertwined. The role of a healthy lifestyle, exercise and diet, stress, age and many other factors are being studied by researchers around the world. Even if it is not always definitively clear how the individual elements are connected: Every single part of the body benefits from a consciously healthy lifestyle. Following general guidelines for healthy living is the best way to boost your immune system as well.

10 quick tips for a healthy immune system:

• Ensure cleanliness and hygiene - at home and at work. Create good conditions for a healthy immune system.
• Wash your hands regularly.
• Eat well and ensure your diet is varied and high in vegetables and fruits.
• Drink lots of still water daily.
• Maintain a healthy body weight.
• Get regular exercise, preferably outdoors, to soak up sunlight and vitamin D. But do not overdo it with very strenuous exercise.
• Don't smoke.
• If you drink alcohol, do it in moderation.
• Make sure you get enough restful sleep.
• Try to keep stress in check and get regular rest.

• Wash your hands regularly and several times a day with soap and water. While this doesn't directly boost your immune system, it does ensure that you don't get infected with pathogens that you pick up from surfaces. Mobile phones, keyboards, door handles are sources of so-called smear infections through which bacteria and viruses that can survive for a long time in the environment are transmitted, e.g. influenza viruses, hepatitis viruses and salmonella.
• Think about your fingernails, too. Pathogens can settle in a layer under your nails.
• If you have a cold, sneeze or cough into the crook of your arm, not into your hand or a tissue. Use disposable tissues to blow your nose and dispose of them in a rubbish bin immediately afterwards. Do not leave used tissues lying around. Also wash your hands after blowing your nose.
• Ensure the right indoor climate. Air that is too dry dries out the mucous membranes in the nose and throat. This makes it easier for pathogens to enter the body. Flu viruses stay longer in the air when it is dry. A humidity of 40 to 60 percent is ideal.
• Ventilate rooms and office areas regularly - briefly but thoroughly, for example by opening opposite windows. The reason we see more colds and flu in winter is purely because we spend more time in rooms or areas with the windows closed. This is how germs are passed on in the family or among colleagues.

Any diet that keeps your body healthy is a diet that is good for your immune defences. Make sure you eat "colourfully." Green, yellow, orange, red or blue vegetables and fruits contain different plant substances, minerals and vitamins. The more varied our supply of these natural substances, the better for our health.

• Your immune system loves varied meals with fresh vegetables, fruit, nuts and wholemeal products, but it also appreciates fish, meat, eggs, milk, dried fruit and frozen vegetables. Some processed products with few ingredients such as bread, cheese, pasta and canned tomatoes definitely have a place in a healthy diet just follow the rule of 'everything in moderation'.
• Herbs and spices have a high value even in small quantities. For example, think of wild garlic, garlic, turmeric, ginger, thyme. As an ingredient or extract, they have antibacterial and antiviral activity.
• Your immune system prefers to avoid foods that have gone through multiple processing steps and contain many ingredients and additives. These "highly processed" foods include, for example, soft drinks, ice cream, pastries, sweets, sausages and other meat products, dry soup mixes and ready meals such as frozen pizza. Look at the ingredient list: If you have more than ten to 15 ingredients, better put the product back on the shelf.
• Vitamins A, C and D as well as the B vitamins B6, folic acid and B12, secondary plant compounds and the trace elements iron, copper, selenium and zinc contribute to the normal function of the immune system. Eat varied and versatile, you will get all these elements all by themselves.
• Numerous foods contain the mentioned trace elements. There is a lot of iron in meat, but also in beans, peas and lentils, which also provide copper. You can also get copper from seafood and nuts. Apart from eggs, fish and meat, selenium can be found in cabbage, mushrooms, asparagus, nuts and onions. Zinc is also found in fish, seafood and meat, but also in cheese, lentils and nuts.
• A diet rich in vegetables will generally provide you with enough vitamins A and C, as well as the equally important dietary fibres. Vitamin C deficiency practically no longer occurs in Central Europe. Incidentally, the body excretes too much unused vitamin C.
• B vitamins are found in green vegetables (broccoli, spinach) in all legumes (beans, peas, chickpeas, lentils), in cereals (whole grains) and animal foods (fish and meat).
• However, vegans who give up all animal foods need to supplement vitamin B12 to avoid deficiency symptoms.
• Vitamin D is a special case. It is assumed that the "sun vitamin" strengthens the body's defences and in particular activates the activity of macrophages. But getting vitamin D from food alone is not so easy. Larger amounts are only found in fatty fish such as salmon or mackerel, in eggs and mushrooms. You can take in smaller amounts via dairy products. Ultimately, however, this only accounts for around 10% of our needs. It is therefore important that the body can also produce vitamin D via the skin and through exposure to UV radiation (see section on "Activity and exercise").
• A normal serum vitamin D level of 50 nanomoles per litre (nmol/l) or 20 nanograms per millilitre (ng/ml) is important for proper immune system function. It is essential that the value is determined by a specialist and a reputable laboratory. So have it measured first before you decide to take vitamin D supplements on your own.
• A worrying vitamin D deficiency is rare. Adults who might be deficient are mainly seniors over 65, bedridden people, people with dark skin and people who do not leave the house at all or only in veils.
• So if you are concerned that your vitamin D level is too low, let it be checked first, then seek advice from your doctor or pharmacist about supplementation. Natural intake (from the sun) does not lead to overdosage, but supplements can.

• Regular exercise is the ideal way to keep the heart and circulation going, increase stress resistance and strengthen the immune system.
• Moderate exercise in the fresh air is sufficient: half an hour to 45 minutes, if possible every day and in all weathers.
• Going for a walk, whether you call it walking or strolling, is good for you and is also easy on the joints. Walking at a brisk but not overwhelming pace is best.
• Endurance sports such as cycling, hiking, jogging or swimming are also ideal.
• Outdoor exercise also counteracts vitamin D deficiency. Even when the sun is not shining, UV rays penetrate the skin (not covered by clothing).
• But also move in wind and weather. If it is dull, cold and wet, walking/running, jogging or hiking in the fresh air will stimulate circulation, moisten the mucous membranes in the respiratory tract - your immune system will be thankful. As the saying goes: "There is no such thing as bad weather, only the wrong clothes."
• If you can't go outdoors at all, weight, muscle strength and endurance if you do a few laps on the exercise bike or treadmill in the gym will also have positive effects on your immune system.
• Regular sauna sessions, about twice a week, can also support your immune system. The most important effects are stress-reducing relaxation and moistening of the mucous membranes.
• However, before you decide to schedule regular sauna visits in addition to your exercise programme, get the okay from your doctor. Caution is advised, for example, with asthma, COPD (because of the increased risk of infection), circulatory problems, tendency to dizziness and in any case with acute infections, colds and fever.
• Don't overdo it: Too much exercise can lead to negative stress and temporarily weaken the immune system. Those who overexert themselves therefore tend to achieve the opposite effect and are then more susceptible to infections.

In addition to diet and exercise, there are other lifestyle factors that have a significant impact on the strength of your body's defences.

• Get enough sleep: While we sleep, the immune cells that our body needs to fight bacteria and viruses renew themselves. This explains why sufficient sleep boosts the immune system. However, people individually need a lot or less sleep. A guideline is six to eight hours per night.
• Stress has a similar effect as too little sleep. With permanent stress, constant tiredness, exhaustion and permanent tension, the immune system also suffers. Find ways and means, also in consultation with your superior and colleagues, to bridge the stressful times as well as possible when the workload is high. If there is stress in the family, look for causes, talk to your partner, seek advice from good friends.
• Don't smoke! Did you know that there are about 4800 chemicals in the tobacco smoke of a cigarette? Addictive nicotine is just one of them. About 90 of these substances have been proven to be carcinogenic, including some that people have deliberately chosen not to consume: Arsenic, lead and benzene, formaldehyde or nitrosamines. Smoking is massively damaging to your health. Possible consequences include COPD, lung cancer and other malignant tumours, emphysema, leukaemia and genetic damage.
• Also, consuming too much alcohol is not good for your health. Alcohol abuse has serious physical and psychological consequences. Alcohol has a depressing effect on the immune system. The white blood cells, especially the so-called phagocytes, which immediately fight harmful intruders, are strongly hindered by alcohol in the blood.
• The good news: Love strengthens the immune system! When people turn to each other affectionately, kiss and cuddle, the hormone oxytocin is released. This in turn inhibits the stress hormone cortisol. In this way, the defences are strengthened indirectly through affection and tender contact with each other.

With more than 300 known cold viruses, it is not uncommon for one of these viruses to slip through the barriers of the immune system despite all precautions and conscious strengthening. This is usually not a problem either: The body of a healthy person usually copes with a banal flu infection within a week or so. But there are ways to make living with a cold a little easier.

1. Tip # 1: Stay at home
   Many also go to work with a cold. However, this is not a good idea. Apart from the fact that the illness is over more quickly if you allow yourself a few days of treatment, you also spread the viruses freely to your colleagues by coughing and sneezing. Don't drag yourself to a birthday party or the gym either. Instead, stay home until you feel fit again.
   
   
2. Tip # 2: Warm up properly
   If you are fever-free, a warm bath will do you good. It increases the body temperature and thereby supports the immune system. Aches and pains in the limbs are relieved by the hot water.
   
   A bath additive with essential oils of spruce or pine needles or thyme has a soothing effect and clears the nose.
   
   
3. Tip # 3: Drink tea and water
   It is always necessary to ensure that you drink enough fluids. It is especially important when you have a cold. Drink two litres of (still) water or tea a day. Herbal teas can also help relieve symptoms. A sore throat is soothed with sage tea. Ginger tea is also beneficial to the immune system.
   
   
4. Tip # 4: A good chicken broth
   The ideal home remedy for colds is home-cooked chicken broth. As we know, a balanced diet supports the body's defences. A warm broth has a soothing effect, keeps you hydrated and is easy to swallow when you have a sore throat. The steam opens the airways and makes breathing easier. Vegetables like carrots, leeks and celery contain vitamins, minerals and antioxidants. Chicken is a source of B vitamins, and a source of protein, both of which support the immune system. Noodles in soup are a good source of energy. We bet you'll feel invigorated and generally much better after a good helping of home-cooked chicken soup. It has to be a "real" one, though. One out of a bag or made with stock cube won't do it.
   
   
5. Tip # 5: Sleep yourself healthy
   Taking it easy, a lot of rest and enough sleep are excellent remedies for a cold, especially if the symptoms are severe and you have a fever. Sleep helps your body recover.
   
   
6. Tip # 6: Fresh air and light exercise
   Dry air in heated rooms aggravates cold symptoms. So you have to ventilate regularly and ensure sufficient humidity. The latter should be about 50 percent.
   
   Those who are already more or less back on their feet can take a relaxing walk to get some fresh air and get the circulation going.
   
   However, sport and major exertion are still off limits, as they strain the cardiovascular system.

1. Does the immune system weaken with age?
   Yes, as the years go by, the resistance to infections decreases. The formation of new B cells declines sharply with age. The immune system can therefore no longer produce new antibodies against every infection. However, older people also have a stock of long-lived B cells that have already been in contact with pathogens. New infections are fought from this stock; however, the defence is not pathogen-specific.
   
   
2. Is the immune system weaker during pregnancy?
   Yes, that is often the case. The body of a pregnant woman has to cope with a whole series of changes within a very short time and also needs extra energy for the development of the embryo. This also challenges the immune system. Pregnant women should therefore definitely strengthen their defences with a healthy and balanced diet, low-impact exercise and stress reduction.
   
   
3. Does drinking water strengthen the immune system?
   Yes. Water is the solvent of the body. It is needed for countless chemical processes in the body, for the transport of nutrients and oxygen, for the excretion of toxins. Lack of fluids means that these tasks are not performed optimally and makes the body more vulnerable. If you drink too little, the mucous membranes are also too dry, allowing pathogens to penetrate more easily.
   
   
4. How can I strengthen my immune system after an infection?
   With all the measures we have described to you in this article. It is true that the immune system also learns through training. But after an infection, it's good to give your immune system a break and replenish it with plenty of exercise, a healthy diet and other measures.
   
   
5. At what time of day is the immune system strongest or weakest?
   We don't know that yet. However, according to the latest research, there are indications that the functioning of the immune system is also controlled by our internal clock. For example, an American physician suspects that the body's own defences are most vulnerable at 11 am in the morning.

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