Top Supplements to Boost Your Immune System: Evidence-Based Picks for 2025

Key Takeaways

• Supplements like vitamin C, vitamin D, and zinc can help shore up your immune system, especially during cold and flu season.
• Gut health, inflammation, and nutrient deficiencies all play a significant role in determining the effectiveness of your immune system.
• Natural supplements and probiotics can provide additional support, but they are most effective when combined with a balanced diet and a healthy lifestyle.

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Think of your immune system as your body’s personal security team, fending off unwanted intruders, like bugs, viruses, and other germs. Taking care of yourself by eating well, getting enough sleep, and managing your stress are the foundational elements of maintaining good health and a robust immune system. However, there may also be nutrients that can be used to supplement a healthy immune system. 

Let's break down exactly which vitamins, minerals, or natural supplements are worth considering when it comes to keeping your immune system in tiptop shape.

4 Essential Vitamins and Minerals for Immune Support

Think of vitamins and minerals as the tools and materials your immune cells need to build a strong defense system. Even small deficiencies in these nutrients can create cracks in that foundation that can chip away at our immune system’s armor.

Vitamin C 

Perhaps the most well-known, and often the first supplement people reach for during cold and flu season, and for good reason. Vitamin C supports the production and function of white blood cells, acting as a powerful antioxidant. Research suggests that it may reduce the duration of colds and help protect against respiratory infections, particularly when taken preventatively.¹ 

Low levels of vitamin C have been linked to a higher risk of contracting illnesses and a longer duration of illness, particularly with viral infections such as the common cold. While eating plenty of fruits and veggies, like oranges, strawberries, bell peppers, and broccoli, can help you meet your needs, some people may benefit from extra support through vitamin C supplements, especially during cold and flu season or times of high stress, which can deplete vitamin C faster.

Vitamin D 

Vitamin D also plays a major role in immune regulation.  Research indicates that low vitamin D levels are associated with an increased risk of infections, including respiratory illnesses such as the common cold and flu. Individuals with a deficiency are more likely to become ill and experience prolonged illness.²

Vitamin D is an essential nutrient that most people should obtain through a balanced diet and/or dietary supplements. Most of the people above the equator are at risk for a vitamin D deficiency because we don’t get enough vitamin D from sunlight alone, especially during the fall and winter months when we’re indoors more or live in places with less sunshine. That’s why many healthcare providers recommend supplementing with vitamin D, especially if your levels are low or even borderline. 

A simple blood test can reveal your current health status. Taking a daily vitamin D3 supplement can help bridge the gap, support immune resilience, and may even help reduce inflammation throughout the body.

Zinc

Zinc is a small mineral that has a mighty impact on our immune system. Getting enough zinc is essential for the development of new immune cells and plays a crucial role in defending against bacteria and viruses. Zinc also helps regulate inflammation levels and support wound healing, which can be beneficial in maintaining a healthy immune system.

Even a mild zinc deficiency can impair immune function and increase the risk of infection or potential respiratory illness. Specifically, the research indicates that taking zinc at the first sign of a cold can help reduce the duration of symptoms.³ Since your body doesn’t store zinc, it’s important to get enough through your diet or supplements. Foods such as oysters, beef, pumpkin seeds, and chickpeas are excellent natural sources of zinc.

For individuals with higher needs, such as those experiencing chronic stress, older adults, or those following a vegetarian diet, supplementation may help fill the gaps to boost immune health.

Selenium

Selenium is vital for proper immune response and antioxidant activity. Brazil nuts are a rich food source, but supplements can help if your diet is lacking in them.

Selenium is a trace mineral, which means a little goes a long way for immune health. It acts as a powerful antioxidant, working in conjunction with enzymes that protect your cells from damage and regulate inflammation levels. Selenium also supports the activation of immune responses, enabling your body to fight off viruses more effectively.⁴

Research indicates that low selenium levels can compromise immune function and potentially exacerbate the progression of certain viral infections.⁴ Brazil nuts are one of the richest dietary sources, but selenium can also be found in fish, eggs, and whole grains.

Because selenium is needed in only small amounts, portion sizes matter. Excessive intake can be harmful, so consult your healthcare provider before supplementing.

5 Herbal and Natural Supplements Enhancing Immunity

Mother Nature also has a pretty impressive medicine cabinet. Some herbs and natural remedies have been used for centuries to support the immune system, and the science behind them is also strong.

Elderberry

Elderberry’s immune-boosting properties stem from its effect on cytokine production. Cytokines are a type of protein used by the immune system to coordinate an effective response to pathogens. Some studies suggest that elderberry extracts can reduce the length and severity of colds and flu by optimizing this process, especially when taken early.⁵ Be aware that raw elderberries are toxic and should always be consumed in cooked or supplement form.

Echinacea

Echinacea is an herb commonly used in teas or supplements to help ward off the common cold. It’s believed to stimulate various parts of the immune system, including white blood cell activity and natural killer cell production, which are part of your body’s first line of defense. While some studies show modest benefits, and others don’t show a significant benefit at all, certain trials suggest that echinacea may reduce the chance of developing a cold or shorten its duration if taken early.⁶

Turmeric

This golden spice contains curcumin, a compound with strong anti-inflammatory properties. Curcumin helps modulate the immune system by lowering chronic inflammation. Curcumin also enhances the activity of T-cells and other immune components, helping the body respond more effectively when pathogens do appear.⁷ 

To maximize the benefits, look for curcumin supplements that include black pepper extract (sometimes labeled as “piperine”), which significantly enhances absorption.

Oregano Oil

Oregano oil is rich in immune-boosting compounds, including carvacrol and thymol, which possess antibacterial properties. These compounds may help break down harmful bugs, effectively weakening or killing them in our systems. 

While oregano oil isn’t a daily supplement for most people, it can be a helpful tool at the first signs of illness or as a short-term defense during flu season.⁸ Because it’s potent, it’s typically used in capsule or diluted oil form. Pro tip: follow the dosage instructions carefully and don’t rely on it long-term.

Ginger

Beyond easing nausea, ginger has anti-inflammatory and antioxidant properties that can support immune health and reduce oxidative stress. Gingerol, its main bioactive compound, has been shown to support immune health by reducing inflammation and oxidative stress, both of which can wear down the immune system over time. 

Ginger may also support the respiratory system and improve circulation, helping immune cells reach the areas they’re needed most.⁹

Probiotics and Gut Health

Your gut isn’t just for digestion; it’s the home base for your immune system, with about 70% of immune cells living there. A healthy gut microbiome helps your body fight off illness by supporting the gut lining (your first line of defense during digestion), “training” immune cells, and helping reduce inflammation. 

Probiotics, found in fermented foods such as yogurt, kefir, sauerkraut, and miso, introduce beneficial bacteria that help maintain a balanced gut and support optimal immune system function. Research indicates that individuals with a diverse gut microbiome exhibit stronger immunity and recover more quickly from illnesses, whereas imbalances in gut bacteria can increase the risk of infections, inflammation, and even autoimmune conditions.¹⁰

Omega-3 Fatty Acids and Immune Modulation

Omega-3 fatty acids, particularly EPA and DHA, found in fatty fish such as salmon, sardines, and mackerel, play a crucial role in reducing inflammation in the body. Most Americans don’t meet the recommendations for seafood twice a week, which means they’re likely missing out on omega-3s in their diet. 

Omega-3s can help reduce inflammation without compromising your body’s ability to fight off infections. While omega-3s are best known for supporting heart and brain health, research also suggests they may offer additional health benefits, including improved immune function and reduced chronic inflammation, which is associated with conditions such as heart disease, autoimmune disorders, and type 2 diabetes.¹¹

If fish isn’t a regular part of your diet, a high-quality fish oil supplement can help you get the immune-supporting benefits of omega-3s. Look for one with at least 500 to 1,000 mg of EPA and DHA combined, third-party tested labels, and in a well-absorbed form, such as triglycerides. A good supplement shouldn’t smell fishy or leave a bad aftertaste, and choosing one with a sustainability certification, such as MSC, is a bonus.

The Bottom Line

Supplements can help strengthen your immune system, particularly when your diet or lifestyle requires a bit of support. But they’re not a substitute for the basics: sleep, stress management, exercise, and a balanced diet. Think of supplements as reinforcements, not the frontline for your overall health.

If you're managing blood sugar levels, always check with your healthcare professional or dietitian before adding new supplements, as some can interact with medications or impact glucose control.

Learn More With Signos’ Expert Advice

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