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. Physical Activity Guidelines for Americans , 2nd edition [PDF Washington, DC: US Department of Health and Human Services; J Sport Health Sci.

Exercise, immunity, and illness. In: Zoladz JA, ed. Muscle and Exercise Physiology. Academic Press. T lymphopaenia in relation to body mass index and TNF—alpha in human obesity: adequate weight reduction can be corrective.

Clin Endocrinol Oxf. Changes in nutritional status impact immune cell metabolism and function. Front Immunol. Increased risk of influenza among vaccinated adults who are obese.

Int J Obes Lond. Obesity as a predictor of poor antibody response to hepatitis B plasma vaccine. Hepatitis B vaccine immunoresponsiveness in adolescents: a revaccination proposal after primary vaccination.

Comparison of a triple antigen and a single antigen recombinant vaccine for adult hepatitis B vaccination. J Med Virol. Reduced tetanus antibody titers in overweight children. Swindt, Christina [corrected to Schwindt, Christina]]. Sleep and health: Everywhere and in both directions.

Arch Intern Med. Skip directly to site content Skip directly to search. Español Other Languages. Six Tips to Enhance Immunity Español Spanish. Minus Related Pages. Food Assistance. Reduced Risk of Death. For More Information Healthy habits to protect against flu.

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. While scientists are still not sure exactly how it helps, vitamin C may reduce the duration of common cold symptoms and improve the function of the human immune system.

For people trying to avoid the sugar in fruit, red bell peppers are an excellent alternative source of vitamin C. Stir-frying and roasting both preserve the nutrient content of red bell peppers better than steaming or boiling, according to a study on cooking methods.

That said, it is important to remember that the immune system is complex. Eating a healthful, balanced diet is just one way to support immune health. It is also essential to be mindful of the other lifestyle factors that may affect immune system health, such as exercising and not smoking.

Anyone who gets frequent colds or other illnesses and is concerned about their immune system should speak to a doctor. In this article, we describe types of foods that may weaken the immune system and others that may help support it. Learn more here. What are the best ways to boost the immune system and can they give you enhanced protection against infections and diseases?

We take a look. While no drinks can quickly give the immune system a boost, staying hydrated and getting plenty of nutrients is essential for immune function.

Elderberry supplements may help support immune system health. The immune system defends the body from invaders such as viruses, bacteria, and foreign bodies. Find out how it works, what can go wrong, and how to…. My podcast changed me Can 'biological race' explain disparities in health?

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Medical News Today. Health Conditions Health Products Discover Tools Connect. The best foods for boosting your immune system. Medically reviewed by Katherine Marengo LDN, R.

Which foods boost the immune system Other ways to boost the immune system Summary. Which foods boost the immune system? Share on Pinterest Blueberries have antioxidant properties that may boost the immune system. Share on Pinterest Garlic may help to prevent colds.

Other ways to boost the immune system. Share on Pinterest Washing hands properly may help make the immune system stronger. How we reviewed this article: Sources.

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