Six Tips to Enhance Immunity

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A healthy lifestyle offers many benefits, including helping to prevent heart disease, type 2 diabetes, obesity, and other chronic diseases. Another important benefit is that healthy routines enhance your immunity.

The immune system is the body’s way of protecting itself from infection and disease; it fights everything from cold and flu viruses to serious conditions such as cancer.

Our immune systems are complex and influenced by many factors. Vaccines, such as the flu vaccine, build immunity against specific diseases. Some additional ways you can strengthen your immune system are eating well, being physically active, maintaining a healthy weight, getting enough sleep, not smoking, and avoiding excessive alcohol use.

Eat Well

Food Assistance

If you need help obtaining nutritious food, see resources at USDA Nutrition Assistance Program. You can also call the USDA National Hunger Hotline at 1–866–3–HUNGRY or 1–877–8–HAMBRE to find resources such as meal sites, food banks, and other social services.

Eating well means emphasizing plenty of fruits and vegetables, lean protein, whole grains, and fat–free or low–fat milk and milk products. Eating well also means limiting saturated fats, cholesterol, salt, and added sugars.

Eating well provides multiple nutrients that support optimal immune function.1,2 Be aware, however, that too much of some vitamins and minerals can be harmful. Talk to your health care provider if you think you need nutritional supplements.

Be Physically Active

Reduced Risk of Death

In a study of more than 500,000 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 150 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.3

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.4,5

Maintain a Healthy Weight

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.6,7 Obesity may also lower vaccine effectiveness for numerous diseases, including influenza,8 hepatitis B,9,10,11 and tetanus.12

Safe ways to help maintain a healthy weight include reducing stress, eating healthy foods, getting enough sleep, and engaging in regular physical activity.

Get Enough Sleep

Scientific evidence is building that sleep loss13 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.

Quit Smoking

Smoking can make the body less successful at fighting disease.  Smoking increases the risk for immune system problems, including rheumatoid arthritis.

Avoid Too Much Alcohol

Over time, excessive alcohol use can weaken the immune system.

In Summary

Immunity is your body’s defense against foreign organisms. Taking care of yourself will help your immune system take care of you.


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2Christ A, Lauterbach M, Latz E. Western diet and the immune system: an inflammatory connectionImmunity. 2019;51(5):794–811. Accessed May 13, 2021.

3US Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition [PDF-14.4MB]. Washington, DC: US Department of Health and Human Services; 2018. Accessed May 13, 2021.

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8Neidich SD, Green WD, Rebeles J, et al. Increased risk of influenza among vaccinated adults who are obese. Int J Obes (Lond). 2017;41(9):1324–1330. Accessed May 13, 2021.

9Weber DJ, Rutala WA, Samsa GP, Santimaw JE, Lemon SM. Obesity as a predictor of poor antibody response to hepatitis B plasma vaccine. JAMA. 1985;254(22):3187–3189. Accessed May 13, 2021.

10Simó Miñana J, Gaztambide Ganuza M, Fernández Millán P, Peña Fernández M. Hepatitis B vaccine immunoresponsiveness in adolescents: a revaccination proposal after primary vaccination. Vaccine. 1996;14(2):103–106. Accessed May 13, 2021.

11Young MD, Gooch WM III, Zuckerman AJ, Du W, Dickson B, Maddrey WC. Comparison of a triple antigen and a single antigen recombinant vaccine for adult hepatitis B vaccination. J Med Virol. 2001;64(3):290–298. doi:10.1002/jmv.1049. Accessed May 13, 2021.

12Eliakim A, Schwindt C, Zaldivar F, Casali P, Cooper DM. Reduced tetanus antibody titers in overweight children. [published correction appears in Autoimmunity. 2006 Jun;39(4):349. Swindt, Christina [corrected to Schwindt, Christina]]. Autoimmunity. 2006;39(2):137–141. Accessed May 13, 2021.

13Zee PC, Turek FW. Sleep and health: Everywhere and in both directions. Arch Intern Med. 2006;166(16):1686-1688.

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