The body's immune system protects against bacteria, viruses, toxins and other potentially harmful elements. When your immune system is strong, you may not notice it at work, but when it's weakened, symptoms of illness can soon follow.

Maintaining a healthy body often starts by taking the steps to give your immune system a boost. And this isn't something that can be done quickly. Watch the Mayo Clinic Minute.

Journalists: Broadcast-quality video natural sound pkg is available in the downloads at the end of the post. Please courtesy: "Mayo Clinic News Network. Between seasonal illnesses and the COVID pandemic, your immune system may be top of mind.

Stephen McMullan , a Mayo Clinic family medicine physician. A form of malnutrition that is surprisingly common even in affluent countries is known as "micronutrient malnutrition.

Older people tend to eat less and often have less variety in their diets. One important question is whether dietary supplements may help older people maintain a healthier immune system. Older people should discuss this question with their doctor. Like any fighting force, the immune system army marches on its stomach.

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.

However, a proper diet can help prepare the body to better fight disease. It doesn't work like that. Make sure to include fresh fruits and vegetables in your daily diet. Don't forget about whole grains and nuts. Vitamin C can stimulate the production of white blood cells, which are key to fighting infections.

Citrus fruits, strawberries, red bell peppers and kiwis are rich in vitamin C. However, high doses of some vitamins can be toxic , especially when taken regularly. Don't forget to drink plenty of water. Try to avoid snacking irregularly. If you snack, choose fresh fruits and raw vegetables rather than foods high in sugar, salt, or fat.

I am just going to say snack on things that are good for your body, that boost your immunity. It's important to maintain your weight within healthy ranges.

One of the measures that can help in measuring and interpreting your weight is body mass index. A BMI from Fat cells are not just passive reservoirs of energy but can secrete hormones that increase inflammation making overweight people more vulnerable to diseases.

Making meal plans and scheduling food intake in advance can help to keep weight under control. Especially for those who work remotely, where the temptation to snack is higher. Studies indicate that sleep plays a crucial role in the functioning of the immune system.

Breathing and muscle activity slow down, freeing up energy for the body to fight off illness. The American Academy of Sleep Medicine and the Sleep Research Society recommend that adults ages 18 to 60 sleep at least seven hours each night.

Insufficient sleep makes it more likely one will catch the common cold or the flu.

Ounce for ounce, red bell peppers contain almost 3 times as much vitamin C mg as a Florida orange 45 mg. Besides boosting your immune system, vitamin C may help you maintain healthy skin.

Beta-carotene, which your body converts into vitamin A , helps keep your eyes and skin healthy. Broccoli is supercharged with vitamins and minerals.

Packed with vitamins A, C, and E, as well as fiber and many other antioxidants , broccoli is one of the healthiest vegetables you can put on your plate. The key to keeping its power intact is to cook it as little as possible — or better yet, not at all. Research has shown that steaming or microwaving are the best ways to keep more nutrients in the food.

Garlic adds flavor to food and has long been used for medicinal purposes. Early civilizations recognized its value in fighting infections. Garlic may also slow down hardening of the arteries, and people use it to treat high blood pressure. Ginger is another ingredient many turn to after getting sick.

Ginger may help decrease inflammation, which can help reduce a sore throat and inflammatory illnesses. It may also help with nausea.

Ginger may also decrease chronic pain and might even possess cholesterol-lowering properties. Similar to broccoli, spinach is healthiest when cooked as little as possible so that it retains its nutrients.

However, light cooking makes it easier to absorb the vitamin A and allows other nutrients to be released from oxalic acid , an antinutrient.

Check out some spinach recipes here. These cultures may stimulate your immune system to help fight diseases. Try to get plain yogurts rather than the kind that are flavored and loaded with sugar. You can sweeten plain yogurt yourself with healthy fruits and a drizzle of honey instead.

Yogurt can also be a great source of vitamin D , so try to select brands fortified with this vitamin. Clinical trials are even in the works to study its possible effects on COVID Research so far suggests that vitamin D deficiency may increase the risk for COVID19 and the severity of disease progression in people with the infection.

Experts therefore believe supplementation may protect people with a vitamin D deficiency. However, there is no evidence that vitamin D can treat a COVID19 infection.

When it comes to preventing and fighting off colds, vitamin E tends to take a backseat to vitamin C. However, this powerful antioxidant is key to a healthy immune system. Nuts, such as almonds , are packed with the vitamin and also have healthy fats.

Adults only need about 15 mg of vitamin E each day. Sunflower seeds are full of nutrients, including phosphorous , magnesium , and vitamins B6 and E. Vitamin E is important in regulating and maintaining immune system function. Other foods with high amounts of vitamin E include avocados and dark leafy greens.

Sunflower seeds are also high in selenium. Just 1 ounce contains nearly half the selenium that the average adult needs daily. A variety of studies , mostly performed on animals, have looked at its potential to combat viral infections such as swine flu H1N1.

You may know turmeric as a key ingredient in many curries. This bright yellow, bitter spice has also been used for years as an anti-inflammatory in treating both osteoarthritis and rheumatoid arthritis. Research shows that high concentrations of curcumin , which gives turmeric its distinctive color, can help decrease exercise-induced muscle damage.

Curcumin has promise as an immune booster based on findings from animal studies with antimicrobial properties. More research is needed.

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.

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Photos courtesy of Michael N. Starnbach, Ph. Every part of your body, including your immune system, functions better when protected from environmental assaults and bolstered by healthy-living strategies such as these: Don't smoke.

Eat a diet high in fruits and vegetables. Exercise regularly. Maintain a healthy weight. If you drink alcohol, drink only in moderation. Get adequate sleep. Take steps to avoid infection , such as washing your hands frequently and cooking meats thoroughly.

Try to minimize stress. A Quiz for Teens Are You a Workaholic? How Well Do You Sleep? Health Conditions Discover Plan Connect. Mental Well-Being. Medically reviewed by Kathy W. Warwick, R. Share on Pinterest. Get enough sleep. Eat more whole plant foods.

Eat more healthy fats. Eat more fermented foods or take a probiotic supplement. Limit added sugars. Engage in moderate exercise. Stay hydrated. Manage your stress levels. Supplement wisely. The bottom line. How we reviewed this article: History. Apr 1, Written By SaVanna Shoemaker. Share this article.

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