Home Remedies for the Immune System: What Ginger, Saunas, Chicken Soup & Co. Really Do

*Note: The header image is AI-generated

By September at the latest, it starts: someone clears their throat in the office, someone sniffs in the train, and suddenly ginger is back at the very front in the supermarket. Maybe you'll reach for the root then too, make yourself a hot lemon, or briefly stand under the cold shower in the morning. That feels good because you can do something yourself before the next cold catches you. However, most cold rituals bring less than expected, because the real work is done by sleep, exercise, and good food.

In this article you will learn which home remedies are proven, which are uncertain and which are a myth, which foods really supply your defenses, how you use the most effective levers in everyday life and from when it is better to ask a doctor.

Table of Contents

1. Ginger, garlic & co. checked: What studies really show

2. Contrast showers and sauna: What is true about hardening

3. Food instead of myth: Which foods really supply the defenses

4. Your immune day to cook: Three recipes for this week

5. From when home remedies are no longer enough

6. What really counts when the cold wave approaches

Ginger, garlic & co. checked: What studies really show

No kitchen home remedy has so far clearly shown that it prevents colds. The things that perform best are precisely the ones that don't look like home remedies at all: sleep and exercise.

The ginger shot is the most striking case. So far, it has only been measured in the laboratory: researchers at TU Munich have shown that the pungent substance gingerol (what burns in the mouth) can put immune cells on high alert. Viruses were not involved in this experiment, nor were humans. However, a cold is caused by viruses. For everyday life, this means: drink your shot if you like the taste, but don't do it out of fear of catching a cold. There is no scientific reason for expensive ready-made shots from the refrigerated shelf.

With garlic, it looks a bit more interesting, but thin. Of eight studies found, only one met the quality criteria of a Cochrane review (2). In it, 146 people took garlic or a placebo for three months. The garlic group had 24 colds, the placebo group 65. However, the affected people were sick for about the same amount of time: around four and a half versus five and a half days. Whether the participants really didn't know what they were swallowing (with that smell!), the reviewers themselves doubt.

Vitamin C remains the classic. A Cochrane evaluation of 29 studies with a good 11,000 participants shows: when taken regularly, it does not prevent colds in the general population, but it moderately shortens them (1). Only with extreme physical exertion, such as marathon runners and female skiers, the risk of catching a cold was halved. Five studies with around 600 people, so a small, very specific group.

Good to know: Garlic in large quantities and ginger extracts can affect blood clotting. Anyone taking blood-thinning medication should best discuss larger quantities with their doctor or pharmacist beforehand. In normal kitchen quantities, this is not an issue.

Contrast showers and sauna: What is true about hardening

Both feel like hardening, but there is no reliable evidence for either for fewer colds. They are still exciting because the studies show something different from what is often claimed.

Contrast showers: fewer days off, same number of infections

The best-known study comes from the Netherlands. Around 3,000 adults who had not showered cold before showered warm for 30 days and ended the shower with 30, 60, or 90 seconds of cold water, after which they continued voluntarily for another two months. Result: The cold shower group reported being sick at work less often, but were just as often sick as the control group.

The fine difference: Days off count whether someone stays at home. Sick days count whether someone is sick. The study found fewer of the former, not the latter. Maybe the cold shower group felt fit enough to work despite a cold. It does not mean more defenses.

The Austrian Cochrane Center views the study critically anyway: Days off due to injuries, operations, and mental illnesses were also counted. A systematic review found no high-quality evidence that cold showering, bathing, or Kneipp applications make common colds less frequent. If the cold minute in the morning wakes you up and puts you in a good mood: great, keep doing it. As a cold brake, it is not suitable according to current knowledge.

Sauna: good data from Finland, but caution when generalizing

In a large Finnish long-term observation of men over around 20 years, regular sauna-goers had fewer cases of pneumonia in a later evaluation. Sounds strong, but it is a cohort study.

Cohort study: Researchers observe a group over years and see who does what and who gets what. Whether the sauna is the cause or whether sauna-goers simply live healthier overall cannot be separated by such a study.

For colds specifically, there is only one small Viennese study from the late 1980s with about 50 people over half a year: The weekly sauna group had fewer colds, but they lasted just as long and were just as severe. It was never repeated. Even the German Sauna Association admits that large long-term studies are missing and dryly notes that the sauna-crazy Finns are not less likely to catch a cold than their neighbors.

Properly done means sauna: only when you are healthy. If the cold is already in you, the dry heat irritates the mucous membranes additionally and strains the circulatory system. You cannot sweat out an infection. The sauna door remains closed during a fever. With cardiovascular pre-existing conditions, you clarify beforehand with a doctor what is suitable for you.

Food instead of myth: Which foods really supply the defenses

What your immune system needs is in completely normal food: Vitamin C, Vitamin D, zinc, selenium, Vitamin A, iron, and folate contribute to the normal function of the immune system. With a vegan diet, it is especially worth looking at Vitamin D, zinc, selenium, iron, and Vitamin A. For Vitamin C and folate, plant-based eaters are mostly well supplied according to the DGE (3).

If you secretly fear that your plant-based diet is to blame for every cold: Totally understandable, but the DGE's picture is more relaxed. It is about a few nutrients that deserve attention, not a fundamental deficiency.

Whether the nutrients reach their destination is often decided in the kitchen. Vitamin C dislikes both prolonged heat and excessive cooking water: steam broccoli briefly rather than boiling it to mush, and feel free to put raw bell peppers on the plate. Beta-carotene needs a little fat; a dash of oil with the carrots is enough. Pair lentils or oats with something rich in vitamin C, as this significantly improves iron absorption. Tea and coffee consumed directly with a meal inhibit it. Sourdough bread, soaked or sprouted legumes reduce phytate content and thus improve zinc absorption.

If food alone is not enough, for example vitamin D in winter or if a blood value is low, a supplement can be useful. A conversation with your doctor is the most reliable way to find out what you really need. You can find vegan immune-support products in the CLAV Immune System category. Go here for the products.

If you want to know more about the individual vitamins and their role in immune defense, this article may be of interest to you: Vitamins for the immune system.

Your immune-boosting day to cook at home: Three recipes for this week

An immune-boosting day requires three meals that cleverly combine the nutrients from the top down. These three ideas are vegan, practical for everyday life, and ready in no more than half an hour.

1. In the morning, have the ginger-lemon shot: finely blend a thumb-sized piece of ginger with the juice of one lemon, half an orange, and a splash of water, strain through a sieve, and season with agave or maple syrup. It offers no protection against colds, but provides a fresh start with some vitamin C. If you use honey, stir it in only after the shot is lukewarm or cold. 

2. For lunch, have a spicy lentil-carrot soup: sauté onion, garlic, and fresh ginger in oil, add diced carrots, red lentils, a little turmeric, and vegetable broth, simmer for around 15 minutes, and blend. Finally, stir in lemon juice and top with raw pepper strips. Lentils provide iron and zinc, vitamin C helps with the iron, and the oil helps with the beta-carotene from the carrots.

3. In the evening, serve the sesame-broccoli-tofu stir-fry: fry tofu cubes until crispy, add the broccoli florets and cook for just a few minutes so they remain al dente, deglaze with soy sauce, a little sesame oil, and grated ginger, and sprinkle generously with sesame seeds. Serve with brown rice. Tofu and sesame provide zinc, while broccoli provides vitamin C and selenium.

For a snack, a handful of pumpkin seeds with a few orange wedges provides zinc plus vitamin C in one go.

When home remedies are no longer enough

Two or three colds per winter are normal in adults and are not a sign of a weak immune system. If you have more than four to six infections a year (even without a fever), or if they occur one after another so that you never fully recover in between, it is worth making an appointment at your family doctor's office. The same applies if a single infection lasts unusually long or runs severe (for example with a high fever for several days or difficulty breathing).

Another ginger tea will not help in this case. Now the goal is to find the cause, and only a doctor can do that.

What really matters when cold season approaches

The most effective measures are the most boring: sleep, exercise, and a colorful plate. A ginger shot, hot lemon, and alternating hot and cold showers above all give you the feeling that you have something in your own hands. That is not nothing, but it is not scientific proof either.

Your next step: choose one or two home remedies from the table above that you already enjoy and continue them with a clear conscience. Put the rest of your energy into the things that count: a regular bedtime, a round of exercise each day, and cooking the lentil soup once this week.

If you want to know more about what matters for your immune defense in the short term and in the long term in everyday life, this article may be of interest to you: Strengthen the immune system, quickly and in the long term.

Sources

(1) Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews, 2013 (CD000980). Go to the summary on Cochrane.

(2) Lissiman E, Bhasale AL, Cohen M. Garlic for the common cold. Cochrane Database of Systematic Reviews, 2014 (CD006206). Go to the summary on Cochrane.

(3) German Nutrition Society (DGE). FAQs on vegan nutrition. Go to the DGE website.

Frequently asked questions about home remedies for the immune system

Is there a vegan alternative to chicken soup?

Yes, a hot vegetable broth provides exactly what makes chicken soup pleasant: warmth, liquid, and salt. Neither has been proven to have an effect on the immune system. With lentils, carrots, and ginger, it becomes a filling meal, such as the soup in the recipes above.

How often should you go to the sauna to get any benefit?

There is no proven minimum number of times to reduce colds. In the small Vienna study, participants went to the sauna once a week. The Finnish data only show associations. Go as often as feels good to you, and only when you are healthy.

Is a cold shower better than alternating hot and cold?

No, neither has been better proven for colds. In the large Dutch study, everyone showered warm first and then cold; this had no effect on the number of illnesses. Decide based on how you feel.

Which vegan multivitamin with vitamin C, D, and zinc is useful if nutrition is not enough?

One that fits your actual deficiencies. You can find out what they are most reliably through a conversation with your doctor or a blood test. Pay attention to amounts close to the daily requirement rather than megadoses, and make sure the product is labeled as vegan. You can find a selection in the CLAV Immune System category.

Is there a vegan zinc supplement with 25 mg?

Yes, CLAV offers zinc bisglycinate with 25 mg per tablet. Zinc contributes to the normal function of the immune system. Whether you need that much is best discussed with your doctor, especially for long-term use. The recommended intake on the packaging is considered the upper limit.

Can home remedies shorten an existing cold?

Hardly, as the evidence is thin. Vitamin C taken regularly moderately shortened colds in the Cochrane review. A high dose started only after symptoms began showed no consistent effect (1). There are indications for zinc, although they are of limited significance.