A high-fiber plant-rich diet with plenty of fruits, vegetables, whole grains, and legumes appear to support the growth and maintenance of beneficial microbes.

Certain helpful microbes break down fibers into short chain fatty acids, which have been shown to stimulate immune cell activity. These fibers are sometimes called prebiotics because they feed microbes.

Therefore, a diet containing probiotic and prebiotic foods may be beneficial. Probiotic foods contain live helpful bacteria, and prebiotic foods contain fiber and oligosaccharides that feed and maintain healthy colonies of those bacteria. Animal studies have found that deficiencies in zinc , selenium , iron , copper, folic acid , and vitamins A , B6 , C , D , and E can alter immune responses.

Epidemiological studies find that those who are poorly nourished are at greater risk of bacterial, viral, and other infections. Eating a good quality diet, as depicted by the Healthy Eating Plate, can prevent deficiencies in these nutrients.

However, there are certain populations and situations in which one cannot always eat a variety of nutritious foods, or who have increased nutrient needs. In these cases a vitamin and mineral supplement may help to fill nutritional gaps. Studies have shown that vitamin supplementation can improve immune responses in these groups.

The elderly are a particularly high-risk group. The immune response generally declines with increasing age as the number and quality of immune cells decreases. This causes a higher risk of poorer outcomes if the elderly develop chronic or acute diseases. In addition, about one-third of elderly in industrialized countries have nutrient deficiencies.

Diet variety may also be limited due to budget constraints or lower interest in cooking for one person; poor dentition; mental impairment; or lack of transportation and community resources to obtain healthy food.

Megadose supplements many times the RDA do not appear justified, and can sometimes be harmful or even suppress the immune system e.

Remember that vitamin supplements should not be considered a substitute for a good diet because no supplements contain all the benefits of healthful foods.

Several herbal supplements have been suggested to boost immune function. What does the research say? Diet Review: Anti-Inflammatory Diet. Food Safety, Nutrition, and Wellness during COVID Ask the Expert: The role of diet and nutritional supplements during COVID The contents of this website are for educational purposes and are not intended to offer personal medical advice.

You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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These barriers include: Skin that keeps out the majority of pathogens Mucus that traps pathogens Stomach acid that destroys pathogens Enzymes in our sweat and tears that help create anti-bacterial compounds Immune system cells that attack all foreign cells entering the body Adaptive or acquired immunity is a system that learns to recognize a pathogen.

Other conditions that trigger an immune response Antigens are substances that the body labels as foreign and harmful, which triggers immune cell activity. What factors can depress our immune system? Older age: As we age, our internal organs may become less efficient; immune-related organs like the thymus or bone marrow produce less immune cells needed to fight off infections.

Aging is sometimes associated with micronutrient deficiencies, which may worsen a declining immune function. Environmental toxins smoke and other particles contributing to air pollution, excessive alcohol : These substances can impair or suppress the normal activity of immune cells.

Excess weight: Obesity is associated with low-grade chronic inflammation. Fat tissue produces adipocytokines that can promote inflammatory processes.

Chronic diseases: Autoimmune and immunodeficiency disorders attack and potentially disable immune cells. Chronic mental stress: Stress releases hormones like cortisol that suppresses inflammation inflammation is initially needed to activate immune cells and the action of white blood cells.

Lack of sleep and rest: Sleep is a time of restoration for the body , during which a type of cytokine is released that fights infection; too little sleep lowers the amount of these cytokines and other immune cells.

Does an Immune-Boosting Diet Exist? Probiotic foods include kefir, yogurt with live active cultures, fermented vegetables, sauerkraut, tempeh, kombucha tea, kimchi, and miso.

Prebiotic foods include garlic, onions, leeks, asparagus, Jerusalem artichokes, dandelion greens, bananas , and seaweed. However, a more general rule is to eat a variety of fruits, vegetables , beans , and whole grains for dietary prebiotics. Chicken soup as medicine? Is there scientific evidence that it aids in healing?

But when breaking down its ingredients, it does appear a worthwhile remedy to try. Second, it provides fluids and electrolytes to prevent dehydration, which can easily occur with a fever. Lastly, a traditional chicken soup recipe supplies various nutrients involved in the immune system: protein and zinc from the chicken, vitamin A from carrots, vitamin C from celery and onions, and antioxidants in the onions and herbs.

A note on COVID The COVID pandemic is creating a range of unique and individual impacts—from food access issues, income disruptions, emotional distress, and beyond. References Childs CE, Calder PC, Miles EA. Diet and Immune Function.

Green WD, Beck MA. Obesity impairs the adaptive immune response to influenza virus. Annals of the American Thoracic Society. Guillin OM, Vindry C, Ohlmann T, Chavatte L. The Positive Effects of Maintaining Healthy Immune Function. Having a strong immune system means that your immune system is healthy and functioning optimally for better immunity.

A well-functioning immune system performs its duties quietly, continuously patrolling the body for any external substances that may have snuck in — initiating a complete defense strategy when necessary. Regardless, taking care of your immune system goes a long way.

In other words, a strong immune system provides better protection, helping you stay healthy. Having a strong immune system helps your wounds heal faster. When you cut, scrape or otherwise damage your skin, the healing process is regulated by immune cells.

i Specialized white blood cells work to keep the wound free of infection and send out chemical messengers, called growth factors, to help repair the damaged area. Thus, a weakened immune system can result in delayed wound healing and those with poor immunity may take longer to heal.

A strong immune system typically results in less down time and overall fatigue. When your immune system is well-functioning, less time and energy is spent having to fight off common ailments. Your skin is your immune systems first line of defense, acting as a physical barrier between your bloodstream and the external environment.

Therefore, having a strong immune system often results in healthier, clearer skin. The same is true for your hair and nails. A strong, well-functioning immune system makes for healthier hair and nails. Research has discovered that specialized immune cells, called regulatory T cells, play a role in hair growth.

iv The good news is that hair and nail nutrients, like vitamin C and E, also support the health of your immune system. There are a number of lifestyle choices that influence the health and vitality of your immune system. Reversely, unhealthy habits, like drinking and smoking, tend to weaken your immune system.

Unfortunately, life can be hectic, stressful and downright overwhelming at times; and there are factors outside of your control that negatively impact your immune system. Oftentimes your immune system could use extra support. he subject of several human trials, the cutting-edge postbiotic offers more comprehensive immune system support than traditional immune boosting supplements, preparing multiple types of immune cells to act quickly when necessary.

Check out our Benefits page to learn how IMMUSE can support your buys lifestyle. Click the button below to find out! Does Your Immune System Need Extra Support? i Strbo, N. Innate and Adaptive Immune Responses in Wound Epithelialization.

Reversely, unhealthy habits, like drinking and smoking, tend to weaken your immune system. Unfortunately, life can be hectic, stressful and downright overwhelming at times; and there are factors outside of your control that negatively impact your immune system.

Oftentimes your immune system could use extra support. he subject of several human trials, the cutting-edge postbiotic offers more comprehensive immune system support than traditional immune boosting supplements, preparing multiple types of immune cells to act quickly when necessary.

Check out our Benefits page to learn how IMMUSE can support your buys lifestyle. Click the button below to find out! Does Your Immune System Need Extra Support?

i Strbo, N. Innate and Adaptive Immune Responses in Wound Epithelialization. Advances in Wound Care. ii Segerstrom, S. Stress, Energy, and Immunity. Curr Dir Psychol Sci. iii Richmond, J.

and Harris J. Immunology and Skin in Health and Disease. Cold Spring Harb Perspect Med. iv Liu, Z. Healthy immune system warriors need good, regular nourishment. Scientists have long recognized that people who live in poverty and are malnourished are more vulnerable to infectious diseases.

For example, researchers don't know whether any particular dietary factors, such as processed foods or high simple sugar intake, will have adversely affect immune function. There are still relatively few studies of the effects of nutrition on the immune system of humans.

There is some evidence that various micronutrient deficiencies — for example, deficiencies of zinc, selenium, iron, copper, folic acid, and vitamins A, B6, C, and E — alter immune responses in animals, as measured in the test tube. However, the impact of these immune system changes on the health of animals is less clear, and the effect of similar deficiencies on the human immune response has yet to be assessed.

So, what can you do? If you suspect your diet is not providing you with all your micronutrient needs — maybe, for instance, you don't like vegetables — taking a daily multivitamin and mineral supplement may bring other health benefits, beyond any possibly beneficial effects on the immune system.

Taking megadoses of a single vitamin does not. More is not necessarily better. Walk into a store, and you will find bottles of pills and herbal preparations that claim to "support immunity" or otherwise boost the health of your immune system.

Although some preparations have been found to alter some components of immune function, thus far there is no evidence that they actually bolster immunity to the point where you are better protected against infection and disease.

Demonstrating whether an herb — or any substance, for that matter — can enhance immunity is, as yet, a highly complicated matter. Scientists don't know, for example, whether an herb that seems to raise the levels of antibodies in the blood is actually doing anything beneficial for overall immunity.

Modern medicine has come to appreciate the closely linked relationship of mind and body. A wide variety of maladies, including stomach upset, hives, and even heart disease, are linked to the effects of emotional stress.

Despite the challenges, scientists are actively studying the relationship between stress and immune function. For one thing, stress is difficult to define. What may appear to be a stressful situation for one person is not for another.

When people are exposed to situations they regard as stressful, it is difficult for them to measure how much stress they feel, and difficult for the scientist to know if a person's subjective impression of the amount of stress is accurate. The scientist can only measure things that may reflect stress, such as the number of times the heart beats each minute, but such measures also may reflect other factors.

Most scientists studying the relationship of stress and immune function, however, do not study a sudden, short-lived stressor; rather, they try to study more constant and frequent stressors known as chronic stress, such as that caused by relationships with family, friends, and co-workers, or sustained challenges to perform well at one's work.

Some scientists are investigating whether ongoing stress takes a toll on the immune system. But it is hard to perform what scientists call "controlled experiments" in human beings.

In a controlled experiment, the scientist can change one and only one factor, such as the amount of a particular chemical, and then measure the effect of that change on some other measurable phenomenon, such as the amount of antibodies produced by a particular type of immune system cell when it is exposed to the chemical.

In a living animal, and especially in a human being, that kind of control is just not possible, since there are so many other things happening to the animal or person at the time that measurements are being taken.

Despite these inevitable difficulties in measuring the relationship of stress to immunity, scientists are making progress. Almost every mother has said it: "Wear a jacket or you'll catch a cold! Probably not, exposure to moderate cold temperatures doesn't increase your susceptibility to infection.

There are two reasons why winter is "cold and flu season. Also the influenza virus stays airborne longer when air is cold and less humid. But researchers remain interested in this question in different populations.

Some experiments with mice suggest that cold exposure might reduce the ability to cope with infection. But what about humans? Scientists have performed experiments in which volunteers were briefly dunked in cold water or spent short periods of time naked in subfreezing temperatures.

They've studied people who lived in Antarctica and those on expeditions in the Canadian Rockies. The results have been mixed. For example, researchers documented an increase in upper respiratory infections in competitive cross-country skiers who exercise vigorously in the cold, but whether these infections are due to the cold or other factors — such as the intense exercise or the dryness of the air — is not known.

A group of Canadian researchers that has reviewed hundreds of medical studies on the subject and conducted some of its own research concludes that there's no need to worry about moderate cold exposure — it has no detrimental effect on the human immune system. Should you bundle up when it's cold outside?

The answer is "yes" if you're uncomfortable, or if you're going to be outdoors for an extended period where such problems as frostbite and hypothermia are a risk. But don't worry about immunity. Regular exercise is one of the pillars of healthy living.

It improves cardiovascular health, lowers blood pressure, helps control body weight, and protects against a variety of diseases. But does it help to boost your immune system naturally and keep it healthy?

Just like a healthy diet, exercise can contribute to general good health and therefore to a healthy immune system. As a service to our readers, Harvard Health Publishing provides access to our library of archived content.

Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

With this Special Health Report, Living Better, Living Longer , you will learn the protective steps doctors recommend for keeping your mind and body fit for an active and rewarding life. Thanks for visiting. Allergens are one type of antigen and include grass pollen, dust, food components, or pet hair.

Antigens can cause a hyper-reactive response in which too many white cells are released. For example, an allergy to mold triggers symptoms of wheezing and coughing in a sensitive individual but does not trigger a reaction in other people.

When pathogens attack healthy cells and tissue, a type of immune cell called mast cells counterattack and release proteins called histamines, which cause inflammation.

Inflammation may generate pain, swelling, and a release of fluids to help flush out the pathogens. The histamines also send signals to discharge even more white blood cells to fight pathogens.

However, prolonged inflammation can lead to tissue damage and may overwhelm the immune system. Autoimmune disorders like lupus, rheumatoid arthritis, or type 1 diabetes are partly hereditary and cause hypersensitivity in which immune cells attack and destroy healthy cells.

Immunodeficiency disorders can depress or completely disable the immune system, and may be genetic or acquired.

Acquired forms are more common and include AIDS and cancers like leukemia and multiple myeloma. Eating enough nutrients as part of a varied diet is required for the health and function of all cells, including immune cells. Certain dietary patterns may better prepare the body for microbial attacks and excess inflammation, but it is unlikely that individual foods offer special protection.

Examples of nutrients that have been identified as critical for the growth and function of immune cells include vitamin C, vitamin D, zinc, selenium, iron, and protein including the amino acid glutamine. Diets that are limited in variety and lower in nutrients, such as consisting primarily of ultra-processed foods and lacking in minimally processed foods, can negatively affect a healthy immune system.

It is also believed that a Western diet high in refined sugar and red meat and low in fruits and vegetables can promote disturbances in healthy intestinal microorganisms, resulting in chronic inflammation of the gut, and associated suppressed immunity.

The microbiome is an internal metropolis of trillions of microorganisms or microbes that live in our bodies, mostly in the intestines. It is an area of intense and active research, as scientists are finding that the microbiome plays a key role in immune function.

The gut is a major site of immune activity and the production of antimicrobial proteins. A high-fiber plant-rich diet with plenty of fruits, vegetables, whole grains, and legumes appear to support the growth and maintenance of beneficial microbes.

Certain helpful microbes break down fibers into short chain fatty acids, which have been shown to stimulate immune cell activity. These fibers are sometimes called prebiotics because they feed microbes.

Therefore, a diet containing probiotic and prebiotic foods may be beneficial. Probiotic foods contain live helpful bacteria, and prebiotic foods contain fiber and oligosaccharides that feed and maintain healthy colonies of those bacteria. Animal studies have found that deficiencies in zinc , selenium , iron , copper, folic acid , and vitamins A , B6 , C , D , and E can alter immune responses.

Epidemiological studies find that those who are poorly nourished are at greater risk of bacterial, viral, and other infections. Eating a good quality diet, as depicted by the Healthy Eating Plate, can prevent deficiencies in these nutrients.

However, there are certain populations and situations in which one cannot always eat a variety of nutritious foods, or who have increased nutrient needs. In these cases a vitamin and mineral supplement may help to fill nutritional gaps.

Studies have shown that vitamin supplementation can improve immune responses in these groups. The elderly are a particularly high-risk group.

The immune response generally declines with increasing age as the number and quality of immune cells decreases. This causes a higher risk of poorer outcomes if the elderly develop chronic or acute diseases. In addition, about one-third of elderly in industrialized countries have nutrient deficiencies.

Diet variety may also be limited due to budget constraints or lower interest in cooking for one person; poor dentition; mental impairment; or lack of transportation and community resources to obtain healthy food. Megadose supplements many times the RDA do not appear justified, and can sometimes be harmful or even suppress the immune system e.

Remember that vitamin supplements should not be considered a substitute for a good diet because no supplements contain all the benefits of healthful foods.

Several herbal supplements have been suggested to boost immune function. What does the research say? Diet Review: Anti-Inflammatory Diet.