How to boost your immune system for flu season: 7 strategies to protect your health

Getting the flu vaccine is your first step in preventing a nasty bout of flu this season, but after you’ve crossed that off your to-do list, your work isn’t over. Taking proactive steps to strengthen your immune system’s defenses can make the difference between keeping you and your family healthy all flu season long, and spending weeks recovering from illness.

But first, can we take a minute to say “thank you” to our immune system? Your immune system is your body’s way of fending off all the germs the world throws at you every day. Unfortunately, a variety of lifestyle factors and unhealthy habits can keep your immune system from operating at full capacity, leaving you susceptible to infections like the flu.

Your immune system is your body's natural defense network, working around the clock to identify and fight viruses, bacteria and other harmful invaders. While you can't control every exposure to the flu virus, you can take meaningful steps to support and strengthen immune system function, so your body is better equipped to respond.

Try these steps for how to boost your immune system

Already feeling under the weather? You’d be surprised how much your daily decisions impact your body’s ability to fight off infection. Make these seven healthy habits part of your everyday routine to help keep your immune system functioning at its highest level.

1. Get your annual flu vaccine

The single most effective way to boost your immune system against influenza is getting vaccinated. The flu shot helps your immune system recognize and fight specific flu strains, significantly reducing your risk of infection and severe illness.

Health officials recommend vaccination for everyone six months and older, and although it is wise to get vaccinated by the end of October, it's never too late during flu season to get protected.

If you're over 65, ask your healthcare provider about high-dose or adjuvanted flu vaccines, which are specifically designed to strengthen immune system response in older adults whose immune function may naturally decline with age.

2. Prioritize quality sleep

Sleep is one of the most powerful yet overlooked ways to boost your immune system. During sleep, your body produces cytokines—proteins that help fight infection and inflammation. Chronic sleep deprivation can reduce these protective proteins while increasing stress hormones that suppress immune function.

Adults who sleep less than six hours per night are up to four times more likely to catch a cold or flu than those who get seven or more hours. To strengthen immune system function through sleep, follow these sleep goals by age:

• 7-9 hours per night for adults
• 8-10 hours for teenagers
• 9-12 hours for school-age children

Tips for better sleep include maintaining a consistent sleep schedule, keeping your bedroom cool and dark, limiting screen time before bed and avoiding caffeine after mid-afternoon.

3. Eat an immune-supporting diet

What you eat directly impacts how well your immune system functions. A nutrient-rich diet provides the building blocks your body needs to produce immune cells and antibodies that fight off infections.

Focus on foods rich in these nutrients, which play critical roles in immune cell production and function:

• Vitamin C (citrus fruits, bell peppers, strawberries, broccoli)
• Vitamin D (fatty fish, fortified dairy, egg yolks)
• Zinc (lean meats, nuts, seeds, legumes)
• Vitamin E (almonds, sunflower seeds, spinach).

And don't overlook the importance of gut health—approximately 70% of your immune system resides in your gut. Incorporate fermented foods like yogurt, kefir, sauerkraut and kimchi to support beneficial gut bacteria that help strengthen immune system responses.

Limit processed foods, excessive sugar and alcohol, all of which can impair immune function and increase inflammation.

4. Exercise regularly (but no need to overdo it)

Moderate, consistent exercise is an excellent way to boost your immune system. Physical activity increases circulation, helping immune cells move through your body more efficiently to detect and fight pathogens. Regular exercise also reduces inflammation and helps immune cells regenerate regularly.

The key word is "moderate." Studies show that 150 minutes of moderate aerobic activity per week—about 30 minutes a day, five days a week—is ideal to strengthen immune system function. Activities like brisk walking, cycling, swimming or dancing all count.

However, intense, prolonged exercise without adequate recovery can temporarily suppress immune function. If you're training for a marathon or engaging in heavy workouts, be extra vigilant about sleep, nutrition and stress management to offset this effect.

5. Manage stress effectively

Chronic stress is a silent saboteur to the immune system. When you're stressed, your body produces cortisol and other stress hormones that, over time, suppress immune function and increase susceptibility to infections.

Finding healthy ways to manage stress is essential if you want to boost your immune system. Evidence-based stress reduction techniques include:

• Mindfulness meditation
• Deep breathing exercises
• Yoga
• Spending time in nature
• Maintaining social connections
• Engaging in hobbies you enjoy

Even brief moments of relaxation can help. Find what works for you and make it a regular part of your routine.

6. Stay hydrated

Proper hydration supports every system in your body, including your immune system. Water helps produce lymph, which carries white blood cells and other immune cells throughout your body. Dehydration can slow this process and make it harder for your body to fight infections.

Aim for about eight 8-ounce glasses of water daily, though individual needs vary based on activity level, climate and body size. Herbal teas, broths, and water-rich fruits and vegetables also contribute to your fluid intake.

During cold, dry winter months, you may need to be more intentional about hydration since you might not feel as thirsty as you do in summer heat.

7. Practice good hygiene and wash your hands

Practicing good hygiene reduces the burden on your immune system by reducing the risk of illness and infection.

Wash your hands frequently with soap and water for at least 20 seconds, especially before eating, after using the restroom, and after being in public spaces. When soap and water aren't available, use hand sanitizer with at least 60% alcohol.

Avoid touching your face, particularly your eyes, nose and mouth, which are entry points for viruses. During peak flu season, consider wearing a mask in crowded indoor spaces, especially if you're at higher risk for complications.

And finally, make sure to clean commonly touched surfaces, like doors and appliance handles, faucets and toilets, regularly to help keep any germs at bay.

You’ve tried to strengthen your immune system, but what if you still get the flu?

Despite your best efforts to boost your immune system and strengthen immune system defenses, you may still get sick. If flu symptoms strike, knowing what to do (and what not to do) when you have the flu can help you recover faster and avoid complications.

Rest as much as possible, stay hydrated and consider over-the-counter medications to manage symptoms like fever and body aches. If you're in a high-risk group (over 65, pregnant, have chronic health conditions, or have a weakened immune system), contact your healthcare provider promptly—as antiviral medications work best when started within 48 hours of symptom onset.

Learning how to boost your immune system doesn't require expensive supplements or dramatic lifestyle changes. You can give your body the tools it needs to defend itself against the flu and other seasonal illnesses by focusing on these seven fundamentals:

1. Flu vaccination
2. Quality sleep
3. Nutritious food
4. Regular exercise
5. Stress management
6. Hydration
7. Good hygiene

Start implementing these strategies today to strengthen immune system function before flu season peaks. Small, consistent changes add up to significant protection over time.

Need help preparing for flu season? Schedule an appointment to get your flu shot or talk with your provider to discuss personalized strategies to keep your immune system strong all season long.