Ways You Can Support Your Immune System This Cold Season

• The immune system functions best when it’s supported by health-promoting daily routines.
• Getting adequate sleep, limiting alcohol intake and eating the rainbow are immune-supportive lifestyle habits.
• Regular exercise, being strategic about supplements and reducing stress can also help.

As we enter the cold and flu season, you may be wondering what steps you can take to avoid the next round of the common cold. Basic hygiene practices like washing your hands are the frontline defense against illness, but your daily routine can also help protect you from germs and sickness. What you eat, how you sleep and your efforts to remain physically active are just a few lifestyle habits at play when it comes to keeping your immune system strong. 

“In addition to diet and exercise, stress management and adequate sleep hygiene are imperative to support your immune system during the fall and winter months,” says Courtney Colbert, RDN. The immune system functions best when it’s supported by health-promoting practices and, fortunately, many are accessible and simple to incorporate into daily practice. 

We asked the experts to share their go-to advice for keeping the immune system functioning at its best this cold season.

1. Eat the Rainbow

“A diet that is mostly made up of colorful plant foods (fruits, veggies, whole grains, nuts and seeds) will provide you with powerful antioxidants that are protective to the immune system,” says Colbert. Eating a diet rich in plant-based foods provides compounds like phytochemicals and flavonoids, which have anti-inflammatory properties and support immune function.

Recommended intakes of fruits and vegetables are between three and five servings per day; eating enough produce will help ensure your intake of essential immune health-promoting nutrients., Colbert also recommends incorporating whole grains, nuts and seeds while also reducing intakes of ultra-processed foods, alcohol and added sugar to further promote healthy immune function.   

These practices will help with your fiber intake and promote healthy gut function, which may play an important role in immunity. “You can consume more fiber by eating foods like whole grains, quinoa, berries, chia and flax seeds and leafy greens,” says Colbert.

2. Avoid or Cut Back on Alcohol

Alcohol has a wide range of effects on health, including the negative effect it has on the immune system. “Excessive alcohol intake reduces the function of immune cell production, making it harder for the body to fight off infection,” says Nanci Dillow, RD. “Alcohol also damages physical barriers necessary for blocking viruses and bacteria from entering the body.” 

If you currently drink alcohol, it’s worth considering cutting back to reduce your total intake, or eliminating it completely to further support your immune function. Instead of imbibing, try a mocktail or one of the increasingly popular nonalcoholic versions of your go-to alcoholic beverage, like nonalcoholic wine or beer. Other beverages, like sparkling water, are excellent choices for staying hydrated while also being fun to drink.

3. Get Moving

“Consistent moderate, aerobic exercise of 150 minutes per week has been shown to have protective effects on the cells that make up a large part of the immune system,” says Colbert. “Increases in blood flow and circulation of oxygen can help with the movement of immune cells (T cells, natural killer cells and antibodies) throughout the blood, which allows for them to get to potential pathogens quicker.” 

Exercise is also known to help reduce stress and decrease inflammation. And it’s beneficial for improving sleep quality, which influences how well the immune system works to fend off illness., But keep in mind that you can overdo it with exercise intensity and frequency, which may backfire when it comes to promoting immune health. Aim for daily physical activity while also allowing plenty of time for rest and recovery, particularly after periods of strenuous exercise.

4. Prioritize Sleep

Current recommendations indicate that most healthy adults require seven to nine hours of sleep per night. “Poor sleep can lead to increased risk of infection, prolonged illness and increased inflammation,” says Dillow. She points to reductions in inflammation, along with increases in immune cell function and antibody production, as the primary drivers of sleep’s positive effect on the immune system.

Inadequate sleep or poor sleep quality is also associated with increased cortisol, a stress hormone that can negatively affect immune function if chronically elevated. 

Promote a healthy sleep environment by reducing exposure to blue light in the hour before bed, by eliminating unnecessary sources of light, and by reducing noise exposure when possible. These practices can help promote a restful night’s sleep, which, in turn, supports healthy immune function.

5. Be Strategic with Supplements

A variety of supplements are marketed as “immune boosting” or protective against illness, but many don’t have the research to back their claims. For example, garlic is often considered an “immune-boosting” supplement, but one review found limited research on its effect on the common cold. Additionally, commonly accepted supplements like vitamin C may have varying effectiveness that depends on factors such as gender and environmental conditions. 

When the diet lacks essential nutrients—a concern for optimal immune function—supplements can help fill the gaps. “A food-first approach is always preferred; however, some may need to consider a supplement if they are unable to consume foods rich in immune-supporting nutrients,” says Dillow. 

Ultimately, supplementation is highly individualized, and people should work with a doctor or registered dietitian to determine which, if any, supplements can offer immune-health benefits. “Supplements are a great tool to fill in nutrition gaps but are not a crutch to be dependent on,” says Dillow.

6. Reduce Stress

The stress response is a natural and protective process that enables the body to respond to short-term stressors. It’s also an important part of optimal immune function. “Acute stress plays a vital role in our immune system by being a crucial component in immune responses,” says Dillow. “However, too much stress can increase the levels and duration of the stress hormone cortisol in the body, potentially leading to chronic inflammation.”

When cortisol is elevated for extended periods, the immune system suffers, which may make the body more susceptible to illness. “Avoiding consistent high-stress situations and adopting stress-management strategies such as low-impact exercise and breath work can be an effective way to balance stress and support the immune system,” says Dillow.

Meal Plan to Try

7-Day No-Sugar Meal Plan for Healthy Immunity

Our Expert Take

Staying healthy throughout the upcoming cold and flu season may feel like an impossible goal, but many practical lifestyle habits can support optimal immune function. Eating a variety of colorful fruits and vegetables, along with other plant foods like whole grains, nuts and seeds, as part of a well-balanced diet that meets your calorie needs can provide antioxidants and other plant compounds known to support the immune system. 

If you choose to add supplements to your diet, be sure to work with a registered dietitian or another health care provider to determine which approach is best for you. Practicing good sleep hygiene while also taking steps to reduce stress allows the body to rest and recover from daily stressors. And even though the weather is getting cooler, it’s still important to exercise when possible, which may mean putting on a few extra layers if you plan to be active outside. Finally, limit or skip the alcoholic beverages and opt for nonalcoholic options to further support a healthy immune system.