6 Signs Your Immune System Is Weakened — and How to Make It Strong Again

Frequent diarrhea or constipation can be a sign of a weak immune system.
Image Credit: PeopleImages/E+/GettyImages

You know your body. And no tracker or app can replace the intuition that helps you sense when you need an extra rest day after an especially intense HIIT class or when you can dial it up another notch during spin class.


You also don't need any kind of special device to know if your immune system is weakened. Your body typically gives you cues when something is amiss.

Video of the Day

Video of the Day

If you notice any of the signs below, your immunity may be less than ideal. But no worries — some lifestyle changes can help give your system a boost so you stand a better chance of staying healthy.

Get tips on how to stay healthy, safe and sane during the novel coronavirus pandemic.

1. Wounds Take Longer to Heal

When we get a cut, scrape or other wound, our immune system kicks into gear, explains Brian Chow, MD, an infectious disease physician at Tufts Medical Center. Once a scab forms, white blood cells help fight off infection while red blood cells help build new tissue. But if your immune system is weakened, all of this can take longer, prolonging the healing process.

Strengthen your immune system: If you have any underlying health condition that causes poor blood circulation, such as diabetes, work with your doctor to manage your condition, Dr. Chow says.

2. You're Stressed Out

Stress sets off our "fight or flight" system, increasing inflammation in the body. If that stress and inflammation becomes chronic, it impairs our immune system, suppressing the cells that protect our bodies from invaders, according to the Cleveland Clinic.


"Long-term stress averts the body's attention more toward survival instincts and less toward issues of maintenance," Dr. Chow explains. "That's why people under stress are more susceptible to more routine-type infections."

Strengthen your immune system: Meditation, yoga, boxing class, walks in nature, calling a friend — you know the drill. As much as you can, find healthy ways to manage and relieve stress. Your mind and body will thank you.


Related Reading

3. You Get Frequent Ear or Sinus Infections

If you experience more than four ear infections or three sinus infections in a year, you may have an immunodeficiency disorder, according to the American Academy of Allergy Asthma and Immunology. Same goes if you get pneumonia twice or need more than two courses of antibiotics in a year.


Strengthen your immune system: If any of this happens to you, Dr. Chow recommends seeing a doctor who specializes in allergies and immunology. He or she can discuss possible treatments.


"Anything that makes us less healthy — a poor diet, smoking, excessive drinking — all of that depresses the immune system."

4. You Always Have a Cold

Although colds may seem less serious than the infections mentioned above, they're still inconvenient. And when you feel like you're always coming down with something, that can be a red flag that your immune system isn't firing on all cylinders. But before you begin to worry, consider your lifestyle.


If you're a mom with a new baby who is going to childcare, "you may be sick a lot because the baby will bring home all kinds of stuff," says Kathryn Boling, MD, a family medicine and primary care physician for Mercy Medical Center.

Similarly, if you are a new preschool or elementary school teacher, you're going to be exposed to a lot of bugs and may take more sick days than normal, Dr. Chow adds.


"But if you are constantly sick and nothing like this is going on, you may have a weakened immune system," Dr. Boling says.

Strengthen your immune system: Studies suggest a vitamin D deficiency may lead to impaired immune responses and increase the risk of infection. So Dr. Boling suggests taking a vitamin D supplement. She advises 2,000 IU daily to her patients in Baltimore, but talk to your physician about what amount may be best for you because too much can be harmful (your doc can check your levels via blood test). The right dosage depends on where you live, your age, your skin tone and how much sunscreen you wear, among other things.



Related Reading

5. You're...So...Tired

Fatigue has many causes, so don't assume that being tired no matter how well you think you slept means your immune system is weak. Dr. Chow recommends first having your doctor run tests to check that you don't have anemia, sleep apnea, an endocrine disorder or another underlying condition. If that all comes out clear, it might be your immunity saying, "Hey! I need help!"

Worse, this can be cyclical, according to a July 2019 paper in Physiological Reviews. When your immune system is fighting to get you healthy, it can make you tired, since that takes energy. But you also may not sleep well. And poor sleep can further weaken your immune system.

Strengthen your immune system: Make sleep a priority. Stick to a regular sleep-wake schedule and make your bedroom dark, cool and reserved for only sleep and sex. Here are more ways to get better sleep.

6. You're in the Bathroom All the Time

While chronic diarrhea or constipation — or both — could be IBS, it also can be a sign of a weak immune system, Dr. Boling says. Or it could be a sign of stress. "And we know stress can make you more susceptible to more infections, usually the more common viruses," Dr. Chow says.

Strengthen your immune system: Eating a diet high in added sugars, refined grains and trans and saturated fats can lead to immune dysfunction and disrupt the gut microbiome. Since our gut plays a role in our immunity, consuming a balanced, healthy diet can also support our immune system.

The Mediterranean diet seems particularly beneficial, according to a December 2016 study in Endocrine, Metabolic & Immune Disorders Drug Targets. Probiotics or eating more fiber may also help, but again, consult your physician or a gastroenterologist, Dr. Chow says, because sometimes these can make things worse.

Related Reading

Bonus Points: More Tips to Shore Up Your Immune System

"Anything that makes us less healthy — a poor diet, smoking, excessive drinking — all of that depresses the immune system," Dr. Boling says. So if you notice any possible signs that your immune system is weakened, look at your lifestyle, she suggests.

In addition to following the tips above to support your immunity, stay active. "Exercise helps counteract the effects of stress and maintain healthy circulation," Dr. Chow says. "This way you are making sure the blood vessels are healthy and your immune cells are getting to the different parts of the body."

Lastly, seek out supportive relationships, Dr. Boling says. "When we are around loving people, it decreases stress and cortisol, so we are healthier overall," she explains.

Concerned About COVID-19?




Is this an emergency? If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911.

Report an Issue

screenshot of the current page

Screenshot loading...