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. 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 have a cold very often

Two or three colds a year, which are over after about ten days, are 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 have a cold, but other ailments also bother you: Infections of the sinuses and/or ears, inflamed gums, fungal infections, pneumonia, more than two conditions requiring treatment with antibiotics.

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 poorly

The healing of wounds is also dependent on the immune system. If you get a scrape, a cut, a burn, your body goes into defensive mode. The injured skin, through which pathogens could penetrate, should be replaced as soon as possible by a new layer of skin. The immune cells help with this. So when wounds heal poorly, 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.

6. You always feel tired and worn out

Tired, although you actually sleep enough? Lacking energy and exhausted? This could also be a sign that 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, autoimmune diseases such as type 1 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 with your primary care physician.

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, varied and high in vegetables and fruits. Drink enough (water).
• Maintain a healthy body weight.
• Get regular exercise, preferably outdoors, to soak up sunlight and thus 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. 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. A layer that can also contain pathogens likes to settle underneath.
• 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 the trash 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 regularly - briefly but thoroughly, for example by opening opposite windows. It has a reason why winter is cold season: You spend more time in rooms with closed windows. This is how germs are passed on in the family or among colleagues.
• In winter, airing will cause the humidity to drop for a short time. Make sure it rises again by using humidifiers, for example. But beware: Not all devices are good - some are bacteria havens. Get information from independent consumer advice (e.g. K-Tipp, Saldo, Stiftung Warentest).

Any diet that keeps your body healthy is a diet that is good for your 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. Processed products with few ingredients such as bread, cheese, pasta, canned tomatoes, and smoked fish or ham definitely have a place in a healthy diet.
• Herbs and spices have a high value even in small quantities. For example, think of wild garlic, nettle, dandelion, garlic, turmeric, ginger, thyme and red coneflower. As an ingredient or extract, they have antibacterial and antiviral activity.
• Your immune system likes 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 soups 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. 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 e.g. take vitamin D supplements on your own.
• A worrying vitamin D deficiency is rare even in our not exactly sun-drenched countries. Babies who are therefore always given vitamin D have an increased risk. 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 does not lead to overdosage, but preparations do.

• Regular exercise is the ideal way to keep the heart and circulation going, increases stress resistance and strengthens 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, it also has positive effects on your immune system, weight, muscle strength and endurance if you do a few laps on the exercise bike or in the gym in the evening after work.
• Kneipp therapy supports the immune system in the long term when used regularly. You can also tread water at home in the bathtub.
• 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. In any case, it should not be less in the long run.
• 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. But there are ways to make living with a cold a little easier.

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.

Tip # 2: Warm up properly

If you are fever-free, a warm bath will do you good. It increases the body temperature and thereby boosts the immune system. Pain in the limbs is 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.

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 relieve symptoms:
Lime-tree blossom tea warms and helps with aching limbs and general malaise. For coughs, thyme tea is the remedy of choice. A sore throat is cured with sage tea. Ginger tea is also beneficial. It stimulates the immune system.

Tip # 4: A good chicken broth

The perfect 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, which boost the immune system, and is also high in protein, which also supports 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. Read more here.

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. During the day you are welcome to take a nap on the sofa, in the evening you should go to bed early. With a bit of luck, you'll be much fitter the next morning.

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. Of course, you need to dress warmly accordingly.
However, sport and major exertion are still taboo, as they strain the cardiovascular system.

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.

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.

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, so that pathogens can penetrate more easily.

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.

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.