Why do I keep getting sick often in the winter? Does cold weather cause you to get sick? If you're wondering (or Googling) these questions, you're not alone. Whether it's a cough, the flu, or the common cold, many people feel like they get sick more often during cold and flu season than in spring and summer.

Keep reading to learn how cold weather affects the immune system, what other factors influence how often you get sick, and how to stay healthy in cold weather.

Does Cold Weather Actually Make You Sick?

It can seem like cold weather makes you sick, especially if you're under the weather more often during the winter or after spending time outdoors in frigid conditions. You may have heard old sayings like "bundle up, or you'll catch a cold." This is a common misconception—cold weather isn't a direct cause of illness.

That said, cold temperatures—particularly a large, rapid drop in temps—can make it easier to catch a sickness.¹ Cold air can dry out your nasal passages, which can weaken your immune system and lower your body's ability to fight off infection. So you might be more susceptible to a viral or bacterial infection, like COVID-19 or strep throat, respectively.^2,3

Simply stepping outside on a cold day won't make you sick on its own—cold outdoor conditions aren't the only thing at play. We'll explore all the possible contributing factors to wintertime illness ahead.

Why Do People Tend to Get Sick More Often During Colder Months?

Multiple environmental, lifestyle, and immune-related factors may contribute to why people become sick more often during colder months, including:

• Cold, dry outdoor air
• Spending more time indoors
• Changes in daily routines
• Environmental changes

Let's look at each in more detail.

Cold, Dry Outdoor Air

As mentioned, being outdoors in very cold conditions can dry out your airways. This can suppress your body's immune defense against airborne infection. So, if you're exposed to someone else who's sick, you might be more likely to catch a cold.^2,3

Some research even suggests that some viruses can survive for longer outside the body in cold, dry conditions. Lower air temperatures may also allow airborne pathogens to stay in the air longer.⁴

Spending More Time Indoors

Wet weather, snow, and frigid outside temps often lead to more time spent indoors with the windows closed. During the winter, this can mean sharing spaces with other people, with little ventilation to help filter out germs and pathogens.

Whether at work, on an airplane, or socializing, close contact with others can expose you to the flu and other seasonal viruses or bacterial infections.⁵ When someone nearby coughs, sneezes, talks, or even breathes, airborne particles could make their way into your system.^6,7

Changes in Daily Routines

Things like travel, holidays, busy schedules, stress, and disrupted daily routines might influence your overall wellness. Healthy habits can be harder to maintain during fall and winter. Some people may eat differently, drink more alcohol, exercise less, struggle to get enough sleep, or make other lifestyle changes that affect general health and immunity.^8,9

Also, it's common to be exposed to more people in indoor settings at work or school during the colder seasons. Based on sheer numbers, this day-to-day proximity in larger groups could allow viruses to spread more easily.¹⁰

Environmental Changes

As seasons change and routines shift, your immune system may respond differently, impacting your susceptibility to sickness and overall well-being. This includes lower humidity (both outdoors and inside with heated indoor air), dry outdoor air, and possible suppressed immune responses.^11,12

Lower vitamin D levels can happen during the winter months with less sunlight exposure. Research suggests that this is associated with suppressed immunity against viral and bacterial infections.^13,14

Why Do You Keep Getting Sick?

Sometimes, frequent sickness can feel like bad luck. Other times, it may seem like something else is going on. Here's what to consider if you keep getting sick.

Recovery May Matter as Much as Exposure

Ongoing physical and mental demands this time of year could leave less time for rest and recovery. Recovery is crucial for giving your body the energy to fight off illness and maintaining a resilient immune system.¹⁵

So, if you're grinding at work, have a jam-packed schedule, and are getting sick without allowing yourself to rest, it could create a cycle that leaves you never quite feeling like your normal, healthy self.

Sleep and Immune Function

Sleep is vital to recovery and plays an important role in supporting healthy immune function. Consistently poor sleep—think logging less than seven hours a night and frequent wake-ups for weeks on end—could take a toll on your overall well-being. Learn more about the connection between sleep and the immune system.⁹

Stress and Everyday Wellness

Occasional overwhelm and small, day-to-day stressors are normal. But if you feel stressed or burnt out more often than not, a fraught mental state could begin to affect multiple bodily systems, including your nervous system and immune system.^16,17

Everyday Habits That May Help Support Immune Resilience

So, what can you do to fend off seasonal illness and support your immune system? Here are some daily habits that may support immune function and help you stay well this season.

Eat a Nutrient-Dense Diet

A varied, balanced diet can help ensure your body gets the nutrients your immune system needs for whole-body health. Prioritize whole foods whenever possible, as they're the foundation of everyday wellness and longevity.

Try to eat a medley of nutrient-dense fruits and vegetables for fiber, vitamins, and minerals, including citrus, berries, leafy greens, and herbs. Add in lean protein (chicken, tofu, fish, beans, etc.) and healthy fats, such as nuts, seeds, avocado, and olive oil.^18,19

Stay Physically Active

We probably don't need to tell you that exercise is good for your health. Still, research suggests that people with good general health may be less susceptible to getting sick.²⁰ What's more, studies show those who exercise regularly might be less likely to contract upper-respiratory tract infections or experience cold symptoms.²¹

Keeping up with a workout plan can be challenging in the coldest season, especially with fewer daylight hours. But an active lifestyle doesn't have to involve structured exercise. All movement counts, including walking, doing housework, taking the stairs, and running errands.

Prioritize Recovery

It's easier said than done, but try to give yourself (and your body) time to recuperate after long workdays, travel, intense exercise, and other high-demand, draining activities. Recovery includes quality sleep, plenty of rest, and managing daily demands. Healthy routines help support the body's natural ability to adapt.

Nutrition and Immune Support During Seasonal Changes

What you eat matters for immune function and overall health. Well-rounded nutrition with balanced meals and a focus on whole foods can help ensure you get essential vitamins, minerals, and macronutrients (complex carbohydrates, protein, and healthy fats) during the cold season and for the long term. Explore which nutrients support immune health.

Targeted Nutritional Support May Complement Healthy Habits

During seasonal changes or times of increased daily demands, some people may benefit from targeted nutritional support, such as multivitamin supplements formulated to support a healthy immune response.

Keep in mind, nutritional support is often most effective when combined with healthy lifestyle habits and guidance from a healthcare practitioner.

Taking a Whole-Body Approach to Seasonal Wellness

Immune health is closely connected to sleep, stress management, movement, and nutrition. Striving to stay healthy with consistent, everyday habits can help keep your immune system resilient throughout the year.

When Frequent Illness May Warrant Medical Evaluation

Healthy habits and holistic well-being through lifestyle changes can go a long way. However, any frequent or recurring illness that doesn't improve may require medical attention from a healthcare professional.

Persistent symptoms could have multiple contributing factors that call for an individualized evaluation. Early conversations with a medical provider can help you catch certain conditions early and determine the right next steps.

Supporting Immune Health Starts with Everyday Wellness

Can you get sick from cold weather? Not directly. Cold weather itself doesn't make you sick, but factors tied to common winter conditions may contribute to more frequent illness. This includes:

• Dry nasal passages
• Possible suppressed immune function
• Longer survival of airborne pathogens
• Spending more time indoors with other people and little ventilation
• Changing daily routines
• Environmental components, such as lower vitamin D levels

Sleep, stress management, nutrition, movement, and recovery all play critical roles in supporting normal immune function. Building consistent wellness habits throughout the year might help support immune resilience during seasonal transitions. And targeted nutritional support may complement healthy lifestyle habits as part of a personalized wellness plan.

Explore high-quality vitamin and mineral supplements to complement daily nutrition and align with evolving lifestyle demands.

References:

1. Open Forum Infectious Diseases. The impact of cold ambient temperature in the pattern of influenza virus infection. https://academic.oup.com/ofid/article/10/2/ofad039/7008468
2. Maturitas. Preventing cold-related morbidity and mortality in a changing climate. https://pmc.ncbi.nlm.nih.gov/articles/PMC3119517/
3. Geophysical Research Letters. Cold waves accelerate the spread of infectious diseases. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2024GL109405
4. Reviews in Medical Virology. Temperature dependent viral tropism: understanding viral seasonality and pathogenicity as applied to the avoidance and treatment of endemic viral respiratory illnesses. https://pmc.ncbi.nlm.nih.gov/articles/PMC8209954/
5. Science of the Total Environment. The impact of cold weather on respiratory morbidity at Emory Healthcare in Atlanta. https://www.sciencedirect.com/science/article/pii/S0048969721076907
6. Clinical and Translational Allergy. The impact of cold on the respiratory tract and its consequences to respiratory health. https://link.springer.com/article/10.1186/s13601-018-0208-9
7. American Journal of Infection Control. Airborne spread of infectious agents in the indoor environment. https://pmc.ncbi.nlm.nih.gov/articles/PMC7115322/
8. Scientific Reports. Impact of shared spaces and daily routines on shared microbiome. https://www.nature.com/articles/s41598-025-13870-y
9. Communications Biology. Role of sleep deprivation in immune-related disease risk and outcomes. https://pmc.ncbi.nlm.nih.gov/articles/PMC8602722/
10. PLOS One. Assessing the impact of different contact patterns on disease transmission: Taking COVID-19 as a case. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0300884
11. Epidemics. Indirect transmission and the effect of seasonal pathogen inactivation on infectious disease periodicity. https://www.sciencedirect.com/science/article/pii/S1755436513000029
12. Environmental Science & Technology. Susceptibility of an airborne common cold virus to relative humidity. https://pubmed.ncbi.nlm.nih.gov/33332096/
13. Journal of Infection and Public Health. Vitamin D deficiency and respiratory health: a narrative review bridging gaps in public health through innovative strategies and sustainable solutions. https://www.sciencedirect.com/science/article/pii/S1876034125003624
14. JBMR Plus. Vitamin D and immune regulation: antibacterial, antiviral, anti-inflammatory. https://academic.oup.com/jbmrplus/article/5/1/e10405/7486312
15. Frontiers in Physiology. Integrated effects of cold acclimation: physiological mechanisms, psychological adaptations, and potential applications. https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2025.1609348/full
16. Nature. Cold season air temperature as predictor of psychological well-being and mental health. https://www.nature.com/articles/s41598-025-02486-x
17. Journal of Clinical Medicine. Immunology of stress: a review article. https://pmc.ncbi.nlm.nih.gov/articles/PMC11546738/
18. Food Science & Nutrition. Common foods for boosting human immunity: A review. https://onlinelibrary.wiley.com/doi/full/10.1002/fsn3.3628
19. Food Production, Processing and Nutrition. Immune boosting functional components of natural foods and its health benefits. https://link.springer.com/article/10.1186/s43014-023-00178-5
20. Environmental Health Perspectives. Global association of cold spells and adverse health effects: a systematic review and meta-analysis. https://pmc.ncbi.nlm.nih.gov/articles/PMC4710591/
21. British Journal of Sports Medicine. Upper respiratory tract infection is reduced in physically fit and active adults. https://bjsm.bmj.com/content/45/12/987