A scratchy throat before a special family visit. A hacking cough going around your book club. As viruses spread during cold and flu season, it’s only natural to wonder if you could be doing more to stay well.

Supporting your immune health means giving your body the nutrients, rest, and care it needs to fight infections. For older adults, that includes balanced meals, regular activity, plenty of sleep, and preventive vaccines. Read on to learn how to boost your immunity during the colder months and what it means to make prevention part of your daily routine.

Can you boost your immune system?

Despite the lofty promises in ads for “immune boosting” supplements, there’s no single vitamin or formula that can magically bolster your immunity. More immune activity isn’t always better, either; an overactive immune response can cause harm. The goal is to have a healthy immune system that responds appropriately to pathogens.

Healthy lifestyle routines can support normal immune function over time. But they don’t guarantee you’ll avoid illness, and they don’t replace vaccination. In fact, according to the Centers for Disease Control and Prevention (CDC), healthy habits and vaccines work together to help lower your risk of serious illness.

What is an immune system?

Your immune system is a complex network of cells, tissues, and organs that help protect you from viruses, bacteria, and other harmful invaders. It includes physical barriers, like your skin and the lining of your digestive tract, as well as cells that recognize and respond to infections. Your body needs the right blend of nutrients (i.e., vitamins and minerals) to function properly.

How does your immune system change with age?

As you get older, parts of your immune system become less effective. Your body may respond more slowly to infections and not respond as well to some vaccines. This helps explain why respiratory illnesses can cause more serious disease and complications in people who are older.

Getting sick in the winter isn’t inevitable, but older adults should be proactive about protecting their health during cold and flu season. Getting vaccinated, choosing nutritious foods, and managing chronic conditions are especially important. It’s also a good idea to talk with your health care provider about your personal risk for flu, COVID-19, and other viral illnesses.

There are special flu vaccines designed for older adults. For people age 65 and older, CDC recommends Fluzone High-Dose, Flublok, or Fluad. Moderna's mRNA-based flu vaccine, mFLUSIVA, is also approved for this age group as well as adults age 50 and older.

How can I boost my immunity naturally?

Eat a balanced diet

For older adults, healthy eating means focusing on nutrient-rich, immunity-boosting foods that support their changing dietary needs. Aim to include plenty of vegetables, fruits, whole grains, protein, and healthy fats in your daily meals. Choose whole foods as much as possible and limit your intake of processed, pre-packaged foods. Frozen vegetables and canned beans can make nourishing, satisfying meals easier to put together when you’re busy or not feeling well.

Exercise regularly

Pick a favorite activity and get moving! Walk around your neighborhood, take a dance or fitness class, work in your garden, or try chair exercises if your mobility is limited. Adults 65 and older should strive for 150 minutes of moderate activity weekly, plus strength and balance activities. Start with what you can comfortably do and build gradually.

If long periods of exercise are challenging for you, try fitting "exercise snacks" into your day. These are short bursts of activity you can do whenever it’s convenient for you. They might involve repeating an everyday movement—like standing up from a chair five times instead of once—or picking up the pace, such as climbing stairs more briskly.

Get enough sleep

Aging doesn’t equate to needing less sleep. Older adults still need 7 to 9 hours each night, just like younger adults. If you’re struggling to get restful nighttime slumber, try these practical sleep tips:

• Keep a consistent schedule. As much as possible, aim to go to bed and wake up at the same time each day.
• Make your bed comfortable. Choose a mattress that supports your body, especially if chronic pain wreaks havoc with your sleep.
• Watch what you eat and drink. Avoid heavy meals, caffeine, nicotine, and alcohol close to bedtime.
• Limit naps. Keep them brief (15-20 minutes) and early in the day.
• Make time to unwind. Try reading a good book, listening to soft music, meditating, or journaling before bed.
• Put screens away. Turn off devices like your smartphone about an hour before bedtime.

If pain or sleeplessness persists, it’s time to talk with your health care provider.

Manage stress

From caregiving responsibilities and grief to loneliness, stress is common among older adults. Unfortunately, unrelenting stress can put immense strain our immune system. It increases levels of the hormone cortisol, which can worsen inflammation. It also lowers levels of white blood cells that helps us ward of wintertime respiratory viruses and other pathogens.

In one study, people who experienced more stress showed signs of an immune system that had aged faster.¹

How can you keep stress at bay? You don’t have to eliminate every worry. Even small steps like taking a short walk, talking to a trusted friend or family member, or doing breathing exercises can help take the edge off anxiety and tension. Choose an activity that feels restorative.

Stay hydrated

Dehydration is a potentially serious but reversible condition that can happen when we don’t consume enough fluids for our body’s needs. It can impair our immunity and our ability to recover from illness.

Older people are more prone to dehydration because:

• Thirst and appetite may decline, making it easier to drink too little.
• The body holds less water with age.
• Some medicines increase fluid loss or dehydration risk.

To prevent dehydration, drink fluids regularly throughout the day. This doesn’t mean you have to guzzle plain water by the gallon—tea, milk, and soups all count toward your fluid intake, too. If you’ve been told to limit fluids because of a medical condition, stick to your provider’s guidance.

Avoid smoking and excessive alcohol

According to CDC, smoking not only damages your lungs; it also impairs your defenses against respiratory infections. If you or someone in your household smokes, ask for help quitting.

Heavy alcohol use can also weaken the immune system by lowering white blood cell count and disrupting those cells’ ability to function normally. Drinking alcoholic beverages too frequently can also harm your health in other ways, such as increasing your risk for falls. Consider avoiding or limiting alcohol to help your body stay strong and healthy as you age.

Snapshot: Immunity-Boosting Foods

Think of these as immune-supporting foods, rather than infection preventers. Variety matters more than finding one “superfood.”

What vitamins and minerals support immunity?

Normal immune function depends on getting the vitamins, minerals, and macronutrients your body requires. The nutrients below are key to fighting winter respiratory viruses:

• Vitamin C: Supports immune cells and tissue repair. Routine supplements don’t prevent colds for most people.
• Vitamin D: Helps regulate immune responses. Ask if your vitamin D levels or health history warrant a supplement.
• Vitamin A: Supports the barriers lining your airways and digestive tract. Vitamin A is also involved in creating healthy white blood cells, which help trap and remove bacteria and other pathogens.
• Vitamin E: Supports immune function by protecting cells  that fight infections from oxidative damage.
• Zinc: Promotes the body’s ability to ward off pathogens by helping immune cells develop and communicate.

Before adding any dietary supplements to your daily regimen, ask your provider or pharmacist about appropriate doses and possible medication interactions. Supplements typically offer the clearest benefit when they correct a deficiency; extra amounts don’t necessarily provide extra protection. And high doses of certain nutrients can be harmful.

Learn more:

• Explore essential vitamins for women over 50
• Learn about the right vitamin D dosage for seniors

Winter immune system support for older adults

Respiratory viruses like the flu, COVID, and RSV can be more dangerous for older adults. Getting vaccinated helps lower your risk of serious illness and hospitalization, even if it doesn’t prevent every infection.

Ask your health care provider or pharmacist if you’re up to date on the vaccines recommended for you. You may be able to get several vaccines at one appointment.

Beyond getting vaccinated, be sure to:

• Wash your hands regularly.
• Improve indoor airflow when possible.
• Avoid close contact with people who are sick.
• Consider a well-fitting mask in crowded indoor spaces.

You’ll be glad to know Medicare covers many important preventive vaccines at no cost to beneficiaries, including the flu and COVID vaccines.

If you do start experiencing cold- or flu-like symptoms, call your provider promptly. Antiviral treatments for influenza and COVID-19 work best when started soon after symptoms begin.  

Frequently asked questions

What are signs of a weak immune system?
Frequent, severe, or unusually persistent infections may require an evaluation from a health care professional. Other signs of a weak immune system include digestive issues and blood disorders (e.g., anemia). Fatigue alone doesn’t mean you have weak immunity. Tell your provider about any concerning patterns you’ve noticed.

How do I boost immunity before travel?
Before you travel, make sure you’re up to date on your flu shot and any other vaccines recommended for you, like COVID and RSV. Aim to get vaccinated at least two weeks before your trip to give your body time to build sufficient protection.

Does your immune system weaken as you get older?
Yes. Our immune function becomes less effective with age, leaving us susceptible to viral illnesses like the flu as well as secondary infections like pneumonia. Your health, medications, and lifestyle habits can also play a role in how well you fight infections.

Does cold weather weaken your immune system?
Cold weather may make it harder for you to fend off viruses. Researchers found that cooler temperatures weaken some of the nose’s natural defenses,² which may partly explain why respiratory infections are more common in winter. Spending more time indoors around others also increases your exposure to contagious illnesses like the flu and COVID.

Sources

1. National Institute on Aging. Social stress contributes to accelerated aging of the immune system, study finds. August 4, 2022. Found on the internet at https://www.nia.nih.gov/news/social-stress-contributes-accelerated-aging-immune-system-study-finds

2. Di Huang, et. al. Cold exposure impairs extracellular vesicle swarm–mediated nasal antiviral immunity. Journal of Allergy and Clinical Immunology. December 6, 2022. Found on the internet at https://pmc.ncbi.nlm.nih.gov/articles/PMC13380700/