How Can I Make My Immune System More Resilient? 10 MD-Approved Strategies
The occasional (or seasonal) cold or flu is a natural part of life. But if you notice you're spending way more time laid up on the couch, taken out by yet another bout of sickness, it may be a sign that your immune system support and resilience aren't optimized. There can be several reasons you keep getting sick. The good news? Many of them are within your control.
1. You're experiencing chronic stress.
Chronic stress (coupled with inadequate sleep) is the No. 1 reason people get sick, according to Heather Moday, M.D., an allergist and immunologist. "When we are run down and cortisol soars, our virus surveillance cells dip and we get sick more easily," she explains. "Cortisol itself interferes with the ability of specific white blood cells called T-cells to proliferate and get signals from the body. In addition, cortisol also lowers an important antibody called secretory IgA, which lines the respiratory tract and gut and is our first line of defense against invading pathogens."
Stress also makes us more likely to engage in unhealthy behaviors, like drinking too much, smoking, and seeking solace in "comfort foods" that are full of excess refined sugar or unhealthy carbs. All of these factors can increase your chances of getting sick.
How to fix it:
Stress is a normal part of life, so you're never going to be able to eliminate it completely, but it's vital to find ways to manage it. If you're chronically stressed, anxious, and overwhelmed, you'll likely have to play around with stress reduction techniques, like meditation, journaling, targeted supplements, and balancing home and work life, until you find a system that works for you.
2. You're not sleeping enough.
Moday explains, lack of sleep makes you more likely to get sick because your body can't fight off pathogens as easily. One study published in Sleep in 2015 looked at the sleep habits of 164 healthy men and women and found that those who were sleeping less than six hours per night were more likely to get the common cold than those who slept for at least seven hours.
How to fix it:
Moday says if you're feeling under the weather, the best thing to do is give in and let your body rest. And when you're feeling better, make sure you're getting at least eight to 10 hours of quality sleep every night to support recovery. The key word here is quality. If you have trouble sleeping through the night, you may need to make some adjustments to your sleep routine.
3. You're not getting enough immune-essential nutrients.
There are several essential macro- and micronutrients (i.e., our body can't make them, so we must consume them daily!) that keep your immune system healthy, but vitamin D, vitamin C, and zinc are Moday's top picks. Vitamin C and zinc are antioxidant powerhouses,* but "humans cannot produce vitamin C [which is chewed up with stress], so we need a constant intake of it," she previously told mbg. "Zinc insufficiency is [also] rampant, and it's such an integral player in immunity."
Daily immunity shield to strengthen your body’s natural defenses*
Vitamin D is a potent immunomodulator, which means it helps regulate and control your immune system and the complex immune cell functions working so hard to keep us healthy.* Unfortunately many people have poor vitamin D status (low levels of vitamin D) since it's only found in small amounts in a few foods we eat. Couple that with less exposure to sunlight, which produces vitamin D3 through our skin, and you have a recipe for inadequate vitamin D and suboptimal immune support and function.
How to fix it:
Moday recommends consuming this immune-essential trio of micronutrients (C, D, zinc) daily through two strategies. First, by eating a well-balanced, nutrient-dense diet (see tips below), and then complementing this approach with a targeted, high-quality nutrition supplement.*
To up your intake of vitamin C-dense foods, focus on fruits and vegetables. To incorporate more zinc-rich foods, Moday recommends oysters, crab, pumpkin seeds, and dark chicken meat.
Vitamin D is found in a limited number of foods (fatty fish, egg yolk, liver, and certain types of UV-irradiated mushrooms), plus fortified sources like cereal, milk, and orange juice. The issue here is dose, since these foods contribute a small amount of vitamin D.
If you live in an area where you don't get sunlight most days, or you have insufficient levels of vitamin D, supplementation is smart.* Work closely with your doctor—and monitor your vitamin D levels—to make sure you're getting enough of this immune-critical nutrient daily.*
4. You don't keep your hands clean.
If 2020-2021 taught us anything, it's that dirty hands are one of the fastest ways we can spread germs and make ourselves sick. Studies show that people touch their face around 23 times per hour, which means over the course of a regular day, you've presented 368 opportunities for germs to enter your body through your eyes, nose, and/or mouth.
How to fix it:
Wash your hands often with soap and warm water, making sure to scrub them for at least 20 seconds. While hand sanitizer is a temporary solution when soap and water aren't available, it doesn't take the place of regular hand-washing—and some hand sanitizers aren't the best choice. Many contain triclosan, an ingredient that's been connected to various health issues and gut imbalance.
Also, try not to touch your face. It takes practice to break the habit, but it will pay off. Not only do you decrease your chances of getting sick, but you may also be able to reduce breakouts, too.
5. You don't get enough exercise—or you get too much.
When it comes to exercise, there's a bit of a Goldilocks situation going on: If you don't get enough, your immunity suffers. But if you get too much, it acts like a bad stressor and can fatigue your body systems—and your immunity suffers.
How to fix it.
While high-intensity exercises are OK sometimes, most of your exercise routine should consist of moderate-intensity exercise and aerobic activity 30 to 60 minutes per day. The effort should mimic brisk walking. As you become more physically fit, your personal definition of "moderate intensity" will change, but pay attention to how you're feeling. Exercise should leave you recharged and energized (albeit a little sweaty), not drained and dragging.
Moday also recommends doing some restorative activities, like yoga, tai chi, and walking, and avoiding heavy exercise if you're sick.
6. You're drinking too much.
Alcohol negatively affects both your innate and adaptive immune systems, damaging T-cells, the natural killer cells that find and destroy pathogens. Alcohol also kills good bacteria in your gut, weakening your defenses and your gut barrier function. What's more, it can trigger inflammation.
While short-term (or acute) inflammation is a good thing and is actually an important part of immunity, long-term (chronic) inflammation leaves you more susceptible to illness and chronic conditions, like heart disease, diabetes, and cancer.
How to fix it:
Limit your alcohol intake as much as possible. While the Dietary Guidelines for Americans recommends no more than two drinks a day for men and one drink a day for women, a meta-analysis published in The Lancet found that an upper limit of 100 grams per week is necessary to prevent negative effects. For reference, one standard drink—a 12-ounce beer, 5 ounces of wine, or 1.5 ounces of liquor—has about 14 grams of alcohol.
7. There's too much sugar in your diet.
Sugar affects your immune system in two ways. "When your blood sugar spikes, the function of white blood cells [part of the innate immune system] is reduced, and this affects our immune system's ability to battle pathogens," Ali Miller, R.D., L.D., CDE, registered dietitian and certified diabetes educator, previously told mbg. "T-cells, which are the cells that regulate the acquired or learned immune system, are also hindered when insulin levels are elevated in excess."
But you don't have to take her word for it. An older, yet still relevant, study published in the American Journal of Clinical Nutrition reported that the efficiency of white blood cells drops by 50% one to two hours after eating sugar, and that immune response lasts up to five hours.
That means, if you're constantly eating sugar (or refined, processed carbs that behave like sugar), your immune system is never functioning optimally.
How to fix it:
Limit sugar and processed carbohydrates as much as you can. Focus on a whole-foods-based diet that's full of nutrient-rich ingredients. When you do have sugar—let's face it, you're not going to avoid it forever—be sure to enjoy in moderation.
8. You're dehydrated.
You may not think of hydration status as a major player in whether or not you get sick, but it's an important piece of the puzzle. Water keeps your mucus membranes lubricated and protected, so viruses, bacteria, and other potentially harmful pathogens can't latch on to the tissue, explains Catherine Waldrop, M.D. On the other hand, when you're dehydrated, your nasal passages dry out and can crack, making it easier for these minuscule microbes to enter your body and make you sick.
Water is critical to most cellular reactions and physiological processes. Water also helps flush toxins out of your body, so if you're dehydrated, your detoxification systems may not be working as well as they should.
How to fix it:
Drink more water! The exact amount you need depends on various factors, like your body weight, activity level, and current climate, but as a general rule, you should aim to drink half your body weight in ounces. That means if you weigh 150 pounds, you'll want to drink at least 75 ounces of water per day.
And don't forget that sometimes dehydration occurs from a lack of minerals. It's a good idea to talk to a health care professional about this, but there are electrolyte supplements or natural "sports" drinks (try to limit sugary sports drinks with artificial colors) that can help replenish the minerals in your body. Or, as Dana Cohen, M.D., integrative medicine physician and co-author of Quench, suggests: Simply add some Himalayan sea salt and a squeeze of lemon to your water a couple of times per day.
9. You take antibiotics too often.
Antibiotics certainly have their place, but if you're prescribed them too often, they can wreak havoc on your gut. Antibiotics kill all bacteria, not just bad bacteria, so if you're constantly taking them, it's likely that your ratio of good bacteria to bad is off. The diversity of your gut and optimal gut health is a key factor in optimal immune health, explains Moday.
Plus, it can take up to six months for your gut to fully return to normal after one course of antibiotics.
How to fix it:
Don't take antibiotics unnecessarily. While antibiotics can be lifesaving against bacterial infections, they're useless for viruses. If you do have to occasionally take antibiotics, work with your doctor to optimize a concurrent probiotic regimen and do all you can to support your gut.
Functional medicine expert Will Cole, IFMCP, DNM, D.C., who believes that the root of all disease begins in your gut, also recommends drinking bone broth. This "liquid gold," as it's often called, contains gelatin, glucosamine, glycine, and minerals that help support your gut and your immune system. The minerals in bone broth also help keep you hydrated.
10. Your immune system is compromised.
If you're doing all of the above—or you seem to get sick no matter what you do—it's possible that you have an underlying condition that's preventing your immune system from functioning as it should.
How to fix it:
If you have a compromised immune system, the best course of action is to work closely with a doctor or a health care professional who can guide you through your condition and develop the right care plan. While all of these tips can help decrease your risk of getting sick, if your immune system isn't working as it should, you'll likely need some extra, targeted help.