As we enter the chilly winter months, you’re probably starting to notice a few things — early holiday decorations, seasonal coffees, and a lot of products and promises to 'boost your immunity.' After all, ‘tis the season for colds, flus, and other viruses.
But the truth is, you don’t actually want to 'boost' your immunity. “The immune system is more about a balance between reacting appropriately and overreacting. If you really ‘boosted’ it, you could send it into overreacting, which could lead to improper function,” says Lifeforce Physician Julia Afridi, DO. This can cause autoimmune disease and other illnesses.
Instead, the goal is to support optimal functioning of the immune system — not with quick fixes, but with holistic habits you can stick to year round.
This is key because “a strong immune system is a cornerstone of overall well-being and optimal bodily function,” says Lifeforce Clinician and functional medicine practitioner Tanya Zucco, PA-C. “The immune system is essential for our survival because it serves as the body's primary defense mechanism against a wide range of threats. Without a properly functioning immune system, we would be highly susceptible to infections and unable to maintain our health.”
But rest assured, you can go on the offense to protect your body’s defense system. We’re sharing everything you need to know about the immune system, plus simple tips to optimize it this winter and beyond.
Immunity 101
“The immune system is a complex network of cells, tissues, and organs in the body that work together to defend against harmful invaders, such as bacteria, viruses, fungi, and other pathogens. Its primary function is to protect the body from infections and diseases,” Zucco says.
It does this in a few important ways. First, the immune system constantly surveys the body for foreign substances, known as antigens, Zucco explains. Our bodies are smart, and they can detect the difference between our own cells and invaders. When the system detects an antigen, it springs into action and creates antibodies to attack and destroy the invader.
The immune system also has a memory of its own. “One of the critical features of the immune system is its ability to remember past encounters with pathogens,” explains Zucco. “This memory allows it to respond more effectively if the same pathogen re-enters the body, providing long-term protection.”
Immunity for Holistic Health and Longevity
We usually talk about immunity in terms of battling colds, but it’s about so much more than sniffles. “The immune system is not only important for fighting short-term challenges like illnesses, but also plays a crucial role in longevity and overall health,” Zucco says.
One big reason for this is inflammation. “The immune system is the propagator of inflammation in our bodies. There is no way to un-entwine them. When you activate inflammation, you're activating your immune system and vice versa,” says Dr. Afridi. “Optimizing your immune system is key to longevity because it reduces the inflammation that drives disease and aging, and it keeps you well for longer.”
A well-functioning immune system can also identify and eliminate cancerous cells and help prevent autoimmune diseases where the system mistakenly attacks the body’s own tissues, Zucco explains. Plus, she says, “Immune cells are involved in maintaining the body's internal balance, or homeostasis. They participate in processes like tissue repair, wound healing, and removal of cellular debris, contributing to overall health and vitality.”
Winter’s Chilling Effect on the Immune System
The immune system does some very cool jobs for us, but unfortunately, the chilly winter months make it tougher for our immunity to report for duty.
To shed some light on why, we can look to the sunshine vitamin. “In winter months, we're inside more and we’re not getting exposed to as much sunlight to create vitamin D,” Dr. Afridi says. “Vitamin D is key for immune system function and optimization.” (Learn more about why vitamin D is vital here.)
Dr. Afridi adds that the cold itself is a stressor that can impact our immunity. “When you're in perpetual cold temperatures, that can drain the body’s resources, so you are left more vulnerable to illness,” she says. Research has shown that the flu virus is more infectious in colder temperatures. A recent study in The Journal of Allergy and Clinical Immunology also found that cold weather dampens the effectiveness of our noses’ natural immune response.
Illnesses can also be in the air, quite literally. Zucco explains that indoor heating systems reduce humidity levels, and dry air makes it easier for viruses to survive and spread. The dryer air from indoor heat can also irritate respiratory passages, helping viruses enter the body and establish infections.
Another cold, hard truth: Winter isn’t the only threat to our immune systems. Both experts agree that lifestyle factors like chronic stress, an unhealthy diet, poor sleep hygiene, dehydration, smoking, excessive alcohol use, and environmental pollutants can negatively impact our immunity. Read on to learn more, plus how to help protect yourself.
5 Tips to Optimize Your Immune System
1. Upgrade Your Grocery List
Why it matters: “Eating well is one of the key ways we can impact the immune system,” Dr. Afridi says. “If you’re eating lots of processed and sugary foods, processing them will pull away resources that would otherwise support the immune system. These types of foods activate inflammation, which detracts from immune function. Also, they tend to have less nutrition, vitamins, and minerals.” Studies have found that deficiencies in zinc, selenium, iron, copper, folic acid, and vitamins A, B6, C, D, and E can impair immune responses.
How to do it: Dr. Afridi suggests swapping sugary foods for plenty of leafy greens and berries, which are packed with antioxidants. “Antioxidants help you clear inflammation, so there is less work for your immune system to do,” she says. She also recommends fresh produce, if it’s available, because cooking can break down some of the nutrients.
Lifeforce Health Coach Kelly Lynch, a busy mom to a toddler who often brings germs home from preschool, has a simple hack for getting more nutrients into her everyday diet. “I have an essential grocery list that I buy every single week with must-haves like berries, citrus fruits, broccoli, nuts, and yogurt,” she says. “These foods have vitamins A, C, and E, antioxidants that help protect the body from damage. I design my shopping list so my family can thrive.”
2. Move Your Body
Why it matters: In addition to its many other perks, exercise “can improve circulation, promote the movement of immune cells throughout the body, and reduce inflammation,” Zucco says. “Regular exercise has been shown to enhance immune response and reduce the risk of chronic diseases.” In fact, a study in the British Journal of Sports Medicine found that regular exercise can reduce the number of days with upper respiratory tract infections.
How to do it: When it comes to your workout, Lynch suggests focusing on quality over quantity. “I’ve learned that a 20- to 30-minute workout is enough to work the main muscle groups and make the most of it,” she says.
Lynch alternates between strength training, HIIT cardio, yoga, and Pilates routines when her daughter is napping (or she’ll do the workouts with her!). Lynch loves the varied routines from trainers Heather Robertson and Juice & Toya, but she says the key is finding something you love. “Find something that is quick and that you enjoy, and remember to give yourself grace if some days it doesn’t happen.”
3. Soothe Stress
Why it matters: All of our experts stress the importance of stress management. “Stress is an internal response to what’s happening externally, and that response will activate inflammation. When it's overactivated, that can lead to the overall immune system being less able to handle what it’s being faced with,” Dr. Afridi says. “The classic example is a college student always getting sick at the end of finals week.”
Zucco adds that long-term stress can lead to the release of stress hormones like cortisol. “When elevated for long periods of time, cortisol can suppress the immune system’s response to infections,” she says.
But don’t stress — you can reverse this response. A meta-analysis in Psychological Bulletin found that stress-reduction interventions were associated with significant improvements in immune function.
How to do it: All of our experts recommend meditation and mindful breathing practices. With these rituals, “you are calming down the internal stress response,” Dr. Afridi says. “When done regularly, you can create a change in your overall response to stress, and that can have a major impact on your immune system.”
Lynch understands that there’s not always time for a long meditation session. “I use an app called Daylio for something called Daily Check-Ins,” she says. “I do it about three times a day to assess my mental and physical being at that point in time. It asks ‘How’s my body doing now? How’s my head space doing now?’ Then, I take an action item like hydrating, making sure I’m eating, or taking a deep breath. Stress tends to build up when we don’t allow ourselves to relieve it. This app helps me to bring awareness and address the stress as it’s currently happening.” (Read about more apps to support stress, sleep, and self-care here.)
4. Rest Up
Why it matters: While you’re counting Z’s, your immune system is making it count. “During deep sleep, the body produces and releases cytokines, which are proteins that help regulate immune responses,” Zucco says. “Sleep also supports the production of immune memory cells. Chronic sleep deprivation can impair these processes, weakening the immune system.”
Research in JAMA Internal Medicine suggests that people who consistently get less than six hours of sleep per night are more susceptible to colds and infections.
How to do it: Six to eight hours of deep sleep is the sweet spot. Lynch prioritizes a strict sleep schedule — but leaves room for the inevitable interruption. “If I’m setting my sleep window for 10:30 pm to 7 am, that gives me enough wiggle room that if my daughter wakes up in the middle of the night I can still get at least seven hours,” she says. “Build the unexpected into your schedule.”
Lynch also suggests that you stop eating at least two hours before bedtime. She says, “If your body is still in digestion mode, it can’t fully recover.” Get more tips for the best rest here.
5. Support with Supplements
Why it matters: Supplements can complement a healthy diet and lifestyle, Zucco says. Certain supplements help enhance immune cell function, reduce inflammation, and support respiratory health.
How to do it: Zucco and Dr. Afridi both recommend vitamin D, vitamin C, and zinc to help optimize the immune system. They also note that herbals such as echinacea, elderberry, astragalus, and andrographis have been traditionally used to support immunity. Zucco adds that, “Probiotics are beneficial bacteria that support gut health, which is closely linked to immune function. A healthy gut microbiome can enhance the body's ability to fight infections.”
Lifeforce’s Peak Defense™ has 23 bioactive ingredients designed for the ultimate immune support, including prebiotics, probiotics, vitamins A, C, D, zinc, selenium, and copper.*
Lynch takes Peak Defense™ year round, and she increases her dose during cold and flu season and when she’s traveling. She says, “It’s not just fighting the cold and flu during winter, but it’s also helping you prepare and defend against everyday immune stressors faster and stronger.”*
Zucco notes that, “The effectiveness and recommended dose of supplements can vary from person to person, so it's important to have a professional review your current health status and biomarkers to determine your specific needs.” You can do this with the Lifeforce Membership, which includes a consultation with a Lifeforce Clinician.
The most important thing is to get ahead of your immunity. “People often don’t think about their immune system until they are already sick,” Lynch says. “Just as we are proactive at Lifeforce about your overall wellness, you have to be proactive about your immune health every day.”
This article was medically reviewed by:
Julia Afridi, DO, ABIHM Board Certified in Family and Osteopathic Medicine
Tanya Zucco, PA-C, Certified Functional Medicine Practitioner and Hormone Expert
*Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult a physician if pregnant/nursing, taking medication, or have a medical condition.
Originally published on November 6, 2023. Updated on November 18, 2024.