Do you constantly have a cold, feel tired and "just not up to par"? Then it may well be that your immune system is weakened.
We want to introduce you to some tips and tricks to get your immune system going again. In this article we will tell you when you should particularly strengthen your immune system, what you should break the habit and what are the reasons for a poor immune system.
The Essentials in Brief
- The immune system consists of cells, messenger substances, antibodies and navigation systems. They ensure that you do not get sick and that you survive illnesses well. However, the immune system is sensitive and can be weakened.
- Preparations with vitamins and minerals do not have to prove their effectiveness. Experts therefore recommend a balanced diet with fruit, vegetables and fish instead.
- Lots of sleep, exercise and little stress can work wonders!
Definition: What is the immune system?
The immune system is the interaction of different parts of your body. Immune cells, antibodies, messenger substances, proteins and navigation systems work hand in hand to do the body good.
The immune system ensures that your body fights off pathogens. At the same time, the immune system must also remove dead cells from its own body, render tumor cells harmless and rebuild the body after infections. (1)
Background: What you should know about strengthening the immune system
In the following paragraphs we want to answer some of the questions that people ask when they want to learn about the weakened immune system.
Why do I need a good immune system?
When the immune system isn't working well, it can't do its job properly. Pathogens such as bacteria, viruses, parasites or fungi can then settle in your body and cause illness or dysfunction.
What happens when the immune system is weakened?
A poor immune system can have several effects. Typical symptoms are:
- tiredness . The immune system uses a lot of energy when you have an infection. In contrast, the energy can be put into other areas if the body is convinced that a problem can be better eliminated in other ways - for example by working more concentrated to eliminate a stress factor. The immune system then works less than it should and you feel tired. (2)
- Common Infections . Frequent infections are a warning sign that your immune system is weakened. In adults, the ÖSPID speaks of a warning signal if there are four or more infections in one year that have to be treated with antibiotics. Infections that come back or an infection that takes an unusually long time to be treated with antibiotics can also be a sign of a weakened immune system. (3)
- Abdominal pain, diarrhea, gas and bloating. Around 80% of all plasma cells are located in the connective tissue of the intestine. They contain the antibody immunoglobulin A. (4) Together with benign bacteria, they defend the digestive tract from infections. When the balance in the intestine is upset, not only is the immune system disturbed, but you also feel it in the form of abdominal pain or diarrhea and flatulence. (5)
- Colds and Sore Throats . Rhinoviruses (HRV) are the main cause of the common cold, which is one of the most common infectious diseases in humans. Adults get a cold two to three times a year, which should usually go away after 7 to 10 days. (6) HRV infections of the upper respiratory tract are usually rather harmless. However, if you have a constant cold, it can be a sign that your body is not producing enough antibodies against the rhinovirus and is having a hard time fighting it. So your immune system is overwhelmed. (7)
- Poor healing of wounds . The immune system is also responsible for healing wounds. When weak, it may take longer than normal for your wounds to heal properly.(8)
When the immune system is weakened, it is called an immune deficiency. This can be congenital or acquired through various causes. See the section below for causes.
What can be the reason that your immune system is weak?
Reasons for a weak immune system can be: (9)
- underweight
- nicotine
- alcohol
- cholesterol
- iron deficiency
- overweight
- zinc deficiency
- Few fruits and vegetables
- vitamin A deficiency
- physical inactivity
- Illegal drugs
For whom is a strong immune system particularly important?
Of course, you should make sure that you always have a functioning immune system. But sometimes that is particularly important.
Where when | Why |
---|---|
Before the vacation | High risk of infection on the plane, non-resident pathogens |
Before operations | Avoid complications, promote healing |
With chemotherapy | Chemotherapy lowers white blood cells |
In toddlers | The immune system must first learn and build up |
For seniors | Functions of the immune system decrease with age |
Before the vacation
Many people want to have everything done at work or around the house before they go on vacation, which leads to stress. This can also be linked to insufficient sleep and poor nutrition. As we already know, all of these things can lead to a weakened immune system.
Viruses and bacteria are particularly easily transmitted on airplanes: Many people stay in a confined space for a long time. The air conditioning systems in the airplanes can also contribute to this. According to a study, the probability of being infected on a plane is twice as high as in everyday life. (10)
In addition, you will be traveling on an airplane with people who have been to different parts of the world. Regionally widespread pathogens that you may have never had contact with before can get into your body in this way. You should therefore strengthen your immune system in particular before a flight.
Before surgeries
The immune system is particularly stressed during an operation and afterwards for wound healing. If the body is in good condition before the operation, there are fewer complications. Endophthalmitis, for example, can occur after eye surgery, leading to complete loss of vision – the highest risk factor for this is immunosuppression, i.e. when the immune system is suppressed. A weak immune system is not automatically a suppressed immune system - such a serious weakness usually requires a pathogen such as measles. (11)
In summary, however, it can be said that the immune system should by no means be weak before an operation.
With chemotherapy
Chemotherapy affects blood formation in the bone marrow. As the number of white blood cells decreases, the immune system also suffers. However, cancer experts advise against taking extra vitamins during chemotherapy. Rather, care should be taken to wash hands after being in public and to avoid crowds.(12)
The other tips below, such as healthy eating, getting enough sleep, and reducing stress, still apply.(13)
In toddlers
At birth, the immune system is already relatively well developed. It develops continuously from the 12th week before birth until the age of 18. So while the cells that produce antibodies are present at birth, they must first learn to respond to various threats. The immune system also has to learn the ability to recognize and remember pathogens.(14)
Only at the age of 5 do you reach the levels in your blood that adults also have. Small children are therefore much more susceptible to diseases than adults. In principle, this is not a bad thing, because contact with the pathogens is necessary for the children to develop antibodies. Nevertheless, the children's immune systems should be kept as robust as possible so that any disease can be fought as well as possible.(15)

Small children get sick more often because their immune system first has to build up antibodies against various pathogens. (Image source: Kelly Sikkema / unsplash)
For seniors
Various functions of the immune system decrease with age. Older people are more susceptible to infections, tumors, malignancies and autoimmune diseases, and vaccination against infectious diseases is less successful than in young people.
It is all the more important to support your immune system through physical activity and other tips (see below).(16)
How can I strengthen my immune system?
There are a number of products that claim to boost your immune system. Experts take a rather critical view of this. Because almost all of these preparations are sold as dietary supplements, the manufacturer does not have to prove that they are actually effective. You should not take any medication or dietary supplement that has not been recommended by your doctor or pharmacist. Instead, you can follow our tips below in the article.
Can I strengthen my immune system without chemicals or purely with plants?
If you look at our tips below, you'll see that in most cases you don't need to take medication to boost your immune system.
There are two herbal active ingredients that are approved for strengthening the immune system: ginseng root and taiga root. According to the WHO, ginseng root extract ensures that immune cells live longer and increases the production of messenger substances. (17)
What if I have immunosuppression?
There are several reasons why the immune system is suppressed: In some cases, it is deliberately brought about by doctors. This is necessary, for example, if you have received a donor organ. In this case, it is not in your interest to strengthen your immune system for the time being. Instead, you should go to the treating doctor for every infection and have yourself checked for tumors regularly.
Once your doctor has given you the go-ahead to stop taking the immunosuppressive drug, you should work on "rebooting" your immune system. You can check out our tips for that later in this article.
Immunosuppression can also be triggered by HIV or similar serious diseases. Those affected by HIV should make sure they live as healthily as possible. Our tips below for supporting the immune system are therefore also relevant for people affected by HIV.
The immune system can be strengthened with preparations from the pharmacy, which usually contain vitamins and minerals. However, experts view their effect critically because they do not have to be proven.
How often should I boost my immune system?
In principle, there is nothing wrong with eating and behaving as healthily as possible. First and foremost, however, it is of course relevant to strengthen your immune system when you notice that it is weakened.
At some points, e.g. B. feeding with vitamins, you should be careful not to consume too much and thus trigger an imbalance in the body.
Do I have to strengthen a child's immune system differently than that of a pensioner?
No. In principle, our tips for strengthening the immune system apply equally to everyone. However, your doctor may prescribe certain medications to boost your immune system. These can then definitely be different for children than for pensioners.
Do animals have an immune system?
All living beings have the so-called "innate immune response". These include reactions that trigger inflammation, protective cell layers, and the complement system. Pathogens are enclosed and neutralized. The innate immune response can reliably fight off the majority of infections.
Vertebrates have also developed the so-called "adaptive immune defence", which protects even more effectively against pathogens. Attackers are precisely identified and the body can specifically produce antibodies for each pathogen. Most domestic animals such as cats, dogs and birds are vertebrates. Humans also have this adaptive immune system. (1) The immune system of pets can be weakened when they are stressed: for example by moving house or a new animal in the household. The change of coat or extreme temperatures can also affect the immune system.
Animals also have an immune system and can have problems with it when they are stressed, for example by moving house or new pets.
Strengthen the immune system: ten tips & tricks for a strong immune system
Are you ready? Then here are ten tips for you to strengthen your immune system again.
Tip 1: Fill up on vitamin D
Vitamin D can regulate the immune system. (18) It boosts the immune system against stress and infection, according to studies. Therefore, it certainly does not hurt to make sure you take vitamin D. However, you should always dose vitamin D as a dietary supplement according to the official recommendations.
You can also move in the sun. Sunlight causes your skin to produce vitamin D.
An unanswered question is the importance of vitamin D in old age. In fact, many people have a long life expectancy despite having little vitamin D in their bodies. (19)
Tip 2: Avoid stress
We know from research that high levels of stress weaken the immune system. Chronic stress is like physical overload and provides the ideal conditions for pathogens to multiply. Therefore, if you want to strengthen your immune system, you should avoid stress as much as possible and spend time relaxing - whether it's with yoga, in the sauna or in some other way. (20)
Tip 3: Exercise
Exercise in the fresh air is good, above all, as a preventive measure. Running, swimming or cycling mobilizes the various "little helpers" of the immune system. Studies have shown that just 20 minutes of exercise (like climbing stairs or jogging) can have an anti-inflammatory effect. (21)
Exercising too hard, on the other hand, can stress the body. If you find that your immune system is a little weak, don't push yourself too hard.

Exercise in the fresh air helps to strengthen your immune system. (Image source: Greg Rosenke / unsplash)
Tip 4: Reduce alcohol and smoking
In order not to weaken your immune system and so that it can get stronger again, you should consume as little alcohol and smoke as possible. (1)
When consuming alcohol, the attack of defenses on invaders is prevented. Smoking damages the immune system in the lungs.
Alcohol consumption blocks two important components that are critical to immune defense: mobilizing defenses and signaling to attack an intruder. This effect lasts for several hours.
Smoking inhales harmful chemical substances. In addition, the cilia of the bronchi are weakened, so that bacteria, viruses and fungi can no longer be easily transported away.
Tip 5: Get enough sleep
The connection between sleep and the immune system has been studied for a long time and is not yet fully understood. Deep sleep in particular could play an important role in our immune system.
According to a Mexican study, people who sleep less than seven hours are three times more likely to catch a cold. (22)
Tip 6: Eat a balanced diet
Nutrition is vital to health, and resource availability has long been recognized as a key factor in parasite-fighting ability, as investing in the immune system is costly. However, food is a complex mix of nutrients, the precise balance of which determines fitness.
A 2019 study of caterpillars established 20 diets that varied in the ratio of nutrients (protein and carbohydrates) and their calorie content. The caterpillars were assigned to different diets and then injected with bacterial cells. 20 hours later, the immune response of the caterpillars was measured. The study authors conclude that diet plays an important role in an animal's ability to generate an adequate immune response, with protein availability being the most important predictor of functional (physiological) immune response. (23)
It is often recommended to eat fruit, vegetables, nuts and legumes. This is mainly due to the nutrients it contains, which support the immune system:
nutrient | food |
---|---|
iron | nuts |
beta-carotene | some fruits, vegetables |
Vitamin B6 | legumes, nuts |
vitamin C | Fruit Vegetable |
vitamin E | nuts |
zinc | legumes |
Legumes contain vitamin B6 and zinc. A 2018 study suggests that vitamin B6 deficiency affects immunity in organisms. Vitamin B6 has multiple effects on immune cells and antibody production, so taking vitamin B6 actively can boost your immunity. (24) You can read more information about zinc in the next tip.
Vitamin C is found in fruits and vegetables but is destroyed by heat, so eat it raw. Vitamin C supports various cell functions of the immune system. To avoid infections, you should get vitamin C through food. The daily requirement of 100 milligrams is in a kiwi - if you know that your immune system is currently weak, there is no harm in taking more vitamin C than that. (25)
Beta carotene is found in many orange and dark green fruits and vegetables. This is the herbal precursor of vitamin A and can promote the growth of immune cells. In addition, it is anti-inflammatory. (26)
Nuts contain vitamin E, vitamin B6, iron and zinc. Eating nuts regularly is therefore particularly useful for a balanced diet.
Tip 7: Zinc and Selenium
Two trace elements that you can also take in specifically are zinc and selenium. Both are associated with the functioning of the immune system.
Zinc ions regulate the signaling pathways in immune cells. (27) To reduce the symptoms of a cold, a combination of vitamin C and zinc is recommended. Selenium is involved in the defense against peroxides. (28)
Tip 8: Heat change
Alternating heat stimulates the immune system. This is because blood circulation is promoted and immune cells are distributed better.
The easiest way to achieve the effect is to take a hot-cold shower, take a foot bath or go to the sauna and then the cold. But beware: If you are feeling too bad, it can do more harm than good to expose yourself to extremes of cold and heat. A 2016 study showed that subjects who took hot-to-cold showers had 29% fewer days absent from work due to illness than the control group who took regular hot showers. It is therefore more of a preventive measure. (29)
Tip 9: Natural remedies (herbs, medicinal and wild plants)
There are two herbal active ingredients that are approved for strengthening the immune system: ginseng root and taiga root. According to the WHO, ginseng root extract ensures that immune cells live longer and increases the production of messenger substances. (17)
Sage is considered a medicinal herb for coughs and colds. Studies show that it expands the bronchi, making it easier to breathe deeply. (30)
Aronia is known for its anti-oxidant effect. The juice of the aronia berry can therefore also be drunk to support a weakened immune system. (31)

Aronia berry juice can support the immune system by having an anti-oxidant effect. (Image source: Merja Partanen / Pixabay)
Echinacea is often recommended as an alleged helper against cold symptoms and the immune system. However, its effect has not been proven, as Stiftung Warentest writes: "Only if the sick take coneflower right at the beginning of a cold", it should help. (32)
Tip 10: Pay attention to healthy intestinal flora
Around 80% of all plasma cells are located in the connective tissue of the intestine. They contain the antibody immunoglobulin A. (4) In order to have a good immune system, you should therefore have a good and healthy intestinal flora. A study from 2014 concludes that wholemeal oat muesli has a regulating effect on intestinal bacteria and can be helpful here. (33)
Conclusion
You can leave the dietary supplements that you get in the pharmacy at ease if you move enough, eat a balanced diet and avoid stress. More sleep and heat changes also help you activate your immune system.
You should not let your immune system down: otherwise you will get sick. Especially before operations and vacation trips, it makes sense to actively strengthen your immune system. You now know how to do that. So good luck and good health!
References
- Lothar Rink, Andrea Kruse, Hajo Haase (2012). Immunology for beginners. In: The immune system: an overview. Heidelberg: Spectrum Academic Publishing House. Source
- Segerstrom S.C. (2007). Stress, Energy, and Immunity: An Ecological View. Current directions in psychological science, 16(6), 326-330. Source
- Austrian self-help group for primary immunodeficiencies: "Warning signals in children". Source
- Suzuki K, Ha S, Tsuji M, & Fagarasan S (2007). Intestinal IgA synthesis: A primitive form of adaptive immunity that regulates microbial communities in the gut. Seminars in Immunology, 19(2), 127-135.
- Li B, Selmi C, Tang R, Gershwin ME, Ma X. The microbiome and autoimmunity: a paradigm from the gut-liver axis. Cell Mol Immunol. 2018;15(6):595-609. Source
- Centers for Disease Control and Prevention: "Common Colds: Protect Yourself and Others" Source
- Kirchberger S, Majdic O, Stöckl J: Modulation of the Immune System by Human Rhinoviruses. Int Arch Allergy Immunol 2007;142:1-10. Source
- dr Joachim Strienz: Something is wrong with my immune system!: What you can do with fibromyalgia, Hashimoto and other diseases. p. 91. W. Zuckschwerdt Verlag, 14.11.2016 Source
- Rink Lothar, Kruse Andrea, and Haase Hajo. Influences on the immune system. In: Immunology for beginners. pp. 247-261. Source
- Hocking, MB, & Foster, HD (2004). Common cold transmission in commercial aircraft: Industry and passenger implications. Source
- Park JC, Ramasamy B, Shaw S, Prasad SD, & Ling RH (2014). A prospective and nationwide study investigating endophthalmitis following pars plana vitrectomy: incidence and risk factors. British Journal of Ophthalmology, 98, 529-533. Source
- Sonja Gibis (2018): "Cancer: Good through chemotherapy". In: apotheken-umschau.de Source
- "Immune system - support and strengthening," In: krebs-und-ich.de Source
- Get PG. Fetal and Neonatal Immunology and the Mucosal Immune System. In: Cantani A, ed. Pediatric Allergy, Asthma and Immunology. Springer Verlag GmbH, ORT 2007: p. 221-268. Source
- Albrecht Bufe, Marcus Peters. Differences between child and adult immune systems Source
- Gabriel, HH (2001). Physical activity, age and immune system. Daugs et al. Source
- WHO monographs on selected medicinal plants. Volume 4. ISBN 978 92 4 154705 5. Source
- Pincikova T, Paquin-Proulx D, Sandberg JK, Flodström-Tullberg M, & Hjelte L (2017). Vitamin D treatment modulates immune activation in cystic fibrosis. Clinical and experimental immunology, 189(3), 359-371. Source
- Chirumbolo, S., Bjørklund, G., Sboarina, A., & Vella, A. (2017). The role of vitamin D in the immune system as a pro-survival molecule. Clinical therapeutics, 39(5), 894-916. Source
- Vitlic, A, Lord, JM, & Phillips, AC (2014). Stress, aging and their influence on functional, cellular and molecular aspects of the immune system. Age (Dordrecht, Netherlands), 36(3), 9631. Source
- StoyanDimitrova, ElaineHultenga, SuziHonga. Inflammation and exercise: Inhibition of monocytic intracellular TNF production by acute exercise via β2-adrenergic activation https://doi.org/10.1016/j.bbi.2016.12.017 Source
- Ibarra-Coronado, EG, Pantaleón-Martínez, AM, Velazquéz-Moctezuma, J., Prospéro-García, O., Méndez-Díaz, M., Pérez-Tapia, M., Pavón, L., & Morales-Montor, J (2015). The Bidirectional Relationship between Sleep and Immunity against Infections. Journal of immunology research, 2015, 678164. Source
- Cotter SC, Reavey CE, Tummala Y, Randall JL, Holdbrook R, Ponton F, Simpson SJ, Smith JA, & Wilson K (2019). Diet modulates the relationship between immune gene expression and functional immune responses. Insect biochemistry and molecular biology, 109, 128-141. Source
- Bingjun Qian, Shanqi Shen, Jianhua Zhang & Pu Jing. Effects of Vitamin B6 Deficiency on the Composition and Functional Potential of T Cell Populations. J Immunol Res. 2017. Source
- Carr, AC, & Maggini, S (2017). Vitamin C and Immune Function. Nutrients, 9(11), 1211. Source
- Kawata, A, Murakami, Y, Suzuki, S, & Fujisawa, S (2018). Anti-inflammatory Activity of β-Carotene, Lycopene and Tri-n-butylborane, a Scavenger of Reactive Oxygen Species. In vivo (Athens, Greece), 32(2), 255-264. Source
- Wessels I, Maywald M, & Rink L (2017). Zinc as a Gatekeeper of Immune Function. Nutrients, 9(12), 1286. Source
- Kieliszek, M., & Błażejak, S. (2016). Current Knowledge on the Importance of Selenium in Food for Living Organisms: A Review. Molecules (Basel, Switzerland), 21(5), 609. Source
- Buijze, GA, Sierevelt, IN, van der Heijden, BC, Dijkgraaf, MG, & Frings-Dresen, MH (2016). The effect of cold showering on health and work: A randomized controlled trial. PloS one, 11(9), e0161749.Source
- Gilani AH, Rehman NU, Khan A, Alkharfy KM. Studies on Bronchodilator Activity of Salvia officinalis (Sage): Possible Involvement of K+ Channel Activation and Phosphodiesterase Inhibition. Phytother Res. 2015;29(9):1323-1329. Source
- Xu J, Mojsoska B. The immunomodulation effect of Aronia extract lacks association with its antioxidant anthocyanins. J Med Food. 2013;16(4):334-342.
- Stiftung Warentest (2018). Cold: What advice helps - and what you can forget. Source
- Connolly ML et al. Hypocholesterole-mic and Prebiotic Effects of a Whole-Grain Oat-Based Granola Breakfast Cereal in a Cardio-Metabolic "At Risk" Population. front microbiol. 2016 Nov 7;7:1675. href="https://www.frontiersin.org/articles/10.3389/fmicb.2016.01675/full" target="_blank">Source