The immune system consists of organs, cells, tissues, and proteins. Together, these carry out bodily processes that fight off pathogens, which are the viruses, bacteria, and foreign bodies that cause infection or disease.

When the immune system comes into contact with a pathogen, it triggers an immune response. The immune system releases antibodies, which attach to antigens on the pathogens and kill them.

Read on to discover 15 foods that boost the immune system. A healthful, balanced diet plays a vital role in staying well. The following foods may help to boost the immune system:.

Researchers found that people who ate foods rich in flavonoids were less likely to get an upper respiratory tract infection, or common cold, than those who did not. Free radicals are molecules that the body produces when it breaks down food or comes into contact with pollutants.

Despite its potential benefits, dark chocolate is high in calories and saturated fat, so it is important to eat it in moderation. Turmeric is a yellow spice that many people use in cooking.

It is also present in some alternative medicines. This is due to the qualities of curcumin , a compound in turmeric. According to a review , curcumin has antioxidant and anti-inflammatory effects. Salmon, tuna, pilchards, and other oily fish are a rich source of omega-3 fatty acids.

According to a report , long-term intake of omega-3 fatty acids may reduce the risk of rheumatoid arthritis RA. RA is a chronic autoimmune condition that occurs when the immune system mistakenly attacks a healthy part of the body.

Broccoli is another source of vitamin C. It also contains potent antioxidants, such as sulforaphane. For these reasons, it is a good choice of vegetable to eat regularly to support immune system health. Sweet potatoes are rich in beta carotene , a type of antioxidant that gives the skin of the potatoes its orange color.

Beta carotene is a source of vitamin A. It helps to make skin healthy and may even provide some protection against skin damage from ultraviolet UV rays. Spinach may boost the immune system, as it contains many essential nutrients and antioxidants, including :.

Vitamins C and E can help support the immune system. Research also indicates that flavonoids may help to prevent the common cold in otherwise healthy people. People use ginger in a variety of dishes and desserts, as well as in teas.

According to a review, ginger has anti-inflammatory and antioxidative properties and is likely to offer health benefits. However, more research is necessary to confirm whether or not it can effectively prevent illness. One review looked at whether taking garlic supplements containing allicin reduced the risk of getting a cold.

The group of participants taking a placebo had more than double the number of colds between them than those taking the garlic supplements. However, the researchers concluded that more research is necessary to determine whether or not garlic can help to prevent colds.

Green tea contains only a small amount of caffeine, so people can enjoy it as an alternative to black tea or coffee. Drinking it may also strengthen the immune system. As with blueberries, green tea contains flavonoids, which may reduce the risk of a cold.

Kefir is a fermented drink that contains live cultures of bacteria that are beneficial for health. Initial research suggests that drinking kefir may boost the immune system. According to a review , various studies have shown that regular consumption of kefir can help with:.

The majority of the research that supports this was carried out on animals or in a laboratory. Researchers need to perform additional studies to understand how kefir may prevent disease in humans.

Sunflower seeds can make a tasty addition to salads or breakfast bowls. They are a rich source of vitamin E , an antioxidant. In the same way as other antioxidants, vitamin E improves immune function. It does this by fighting off free radicals, which can damage cells.

Almonds are another excellent source of vitamin E. They also contain manganese, magnesium , and fiber.

A small handful or a quarter of a cup of almonds is a healthful snack that may benefit the immune system. Oranges and kiwis are an excellent source of vitamin C, which is the vitamin that many people turn to when they feel a cold developing.

In a study of more than , US adults, those who met aerobic and muscle-strengthening physical activity guidelines were about half as likely to die from flu and pneumonia as adults who met neither guideline.

For adults, weekly physical activity guidelines call for at least minutes of moderate-intensity aerobic activity such as 30 minutes a day for 5 days plus two days of muscle-strengthening activities. Regular physical activity helps you feel better, sleep better, and reduce anxiety.

Combined with eating well, physical activity can help a person maintain a healthy weight. Following the physical activity recommendations for your age provides immediate and long—term benefits.

For example, being physically active helps protect you from the flu. Emerging research also suggests that physical activity may potentially benefit immunity. Excess weight can affect how your body functions.

Obesity, defined as a body mass index BMI of 30 or more in adults, is linked to impaired immune functions. Safe ways to help maintain a healthy weight include reducing stress, eating healthy foods, getting enough sleep, and engaging in regular physical activity.

Scientific evidence is building that sleep loss 13 can negatively affect different parts of the immune system. This can lead to the development of a wide variety of disorders. See the recommended hours of sleep per day for your age. Smoking can make the body less successful at fighting disease.

Smoking increases the risk for immune system problems, including rheumatoid arthritis. Over time, excessive alcohol use can weaken the immune system. Taking care of yourself will help your immune system take care of you. Diet and immune function. Accessed May 13, Western diet and the immune system: an inflammatory connection.

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