Highest effect
Magnesium
Mineral
Impact
Highest effect
Magnesium is required for the proper function of T-cells and B-cells, antibody production, and the regulation of inflammation. Widespread deficiency can significantly impair both innate and adaptive immune responses, making adequate levels crucial for resilience.
Vitamin A
Vitamin
Impact
Highest effect
Critical for the health of mucosal surfaces in the respiratory tract and gut, which are the body's first line of defense. Vitamin A is also vital for the proper function of T-cells, B-cells, and Natural Killer cells, making it essential for both innate and adaptive immunity.
Vitamin C
Vitamin
Impact
Highest effect
Typical dose:500–2000 mg / day
Vitamin C contributes to immune defense by supporting epithelial barrier function against pathogens and enhancing the activity of immune cells like phagocytes and T-cells. Its antioxidant properties also protect these cells from damage during the high oxidative stress of an infection.
Vitamin D
Vitamin
Impact
Highest effect
Typical dose:1000–5000 IU / day
Acts as a crucial signaling molecule that modulates both the innate and adaptive immune systems. Vitamin D enhances the pathogen-fighting effects of monocytes and macrophages and decreases inflammation, making it essential for both preventing and responding to illness.
Zinc
Mineral
Impact
Highest effect
Typical dose:15–50 mg / day
Zinc is a critical cofactor for hundreds of enzymes and is vital for immune cell (T-cells, NK cells) proliferation and communication. Adequate levels are required for a proper immune response, while acute supplementation can inhibit viral replication in the upper respiratory tract.
High effect
European Elder
Botanical
Impact
High effect
Typical dose:600–1500 mg / day
Also known as Elderberry, its compounds can block viral entry into cells and enhance the body's immune response to viruses. It is particularly effective against several strains of influenza and common cold viruses, making it a top-tier choice for acute care.
Lactoferrin
Other
Impact
High effect
Typical dose:200–500 mg / day
Lactoferrin, found in colostrum and other bodily fluids, exerts its effects by sequestering iron that bacteria need to grow and by directly disrupting viral and bacterial cell membranes. It helps modulate the immune response and inflammation, making it highly effective for acute support.
Maitake Mushroom
Botanical
Impact
High effect
Typical dose:500–1500 mg / day
The D-fraction in Maitake is a specific beta-glucan known to strongly activate macrophages, NK cells, and T-cells. This enhances the body's surveillance and pathogen-clearing capabilities, making it a valuable tool for bolstering overall immune defense.
Monolaurin
Other
Impact
High effect
Typical dose:300–3000 mg / day
Derived from lauric acid, monolaurin integrates into and destabilizes the lipid envelopes of certain viruses and the cell membranes of some bacteria. This mechanism disrupts pathogen integrity, helping to reduce pathogen load during an active infection.
Omega-3
Fatty Acid
Impact
High effect
Typical dose:1000–3000 mg / day
The fatty acids EPA and DHA are precursors to specialized pro-resolving mediators (SPMs) that actively turn off the inflammatory response. This helps ensure that the immune reaction is effective but not excessive, which is vital for both acute recovery and long-term immune health.
Propolis
Botanical
Impact
High effect
Typical dose:250–1000 mg / day
Contains a high concentration of flavonoids and phenolic compounds that have direct antiviral and antibacterial effects. It also stimulates immune cell activity, making it highly effective for both preventing and treating upper respiratory infections.
Selenium
Mineral
Impact
High effect
Typical dose:55–200 mcg / day
Selenium is a key component of the powerful antioxidant enzyme glutathione peroxidase. It helps regulate inflammation and oxidative stress, preventing tissue damage during an infection. Deficiency is linked to impaired immune function and increased viral virulence.
Moderate effect
Astragalus
Botanical
Impact
Moderate effect
Typical dose:500–2000 mg / day
Astragalus appears to enhance the activity of various immune cells, including T-cells and natural killer cells, improving the body's ability to fight off pathogens. It is best used for long-term prevention and building resilience rather than for treating acute infections.
Blue-Green Algae
Botanical
Impact
Moderate effect
Typical dose:1–5 grams / day
Spirulina and other blue-green algae can enhance the function of NK cells and macrophages. While beneficial for overall wellness and immune system readiness, it lacks the strong, targeted evidence for treating acute infections that higher-tier supplements possess.
Cordyceps
Botanical
Impact
Moderate effect
Typical dose:1000–3000 mg / day
Cordyceps contains polysaccharides and other compounds that can enhance the activity of macrophages and natural killer cells, key components of the innate immune system. It also supports oxygen utilization and energy production, which can be beneficial during recovery from illness.
Eleuthero
Botanical
Impact
Moderate effect
Typical dose:200–600 mg / day
By mitigating the immunosuppressive effects of chronic stress, Eleuthero helps maintain immune system readiness. It can enhance the activity of T-lymphocytes and NK cells, making it useful for long-term resilience rather than acute infection treatment.
Glutamine
Amino Acid
Impact
Moderate effect
During illness or stress, immune cells like lymphocytes and macrophages have a high demand for glutamine as their preferred energy source. Supplementation supports their optimal function and proliferation. It also strengthens the gut lining, preventing pathogens from entering the bloodstream.
Green Tea
Botanical
Impact
Moderate effect
The primary catechin in green tea, EGCG (epigallocatechin gallate), has shown an ability to inhibit the replication of various viruses in vitro, including influenza. It also helps balance the immune response and reduce excessive inflammation, supporting both prevention and recovery.
Vitamin E
Vitamin
Impact
Moderate effect
Vitamin E is vital for maintaining the integrity of cell membranes, protecting them from oxidative stress generated during an infection. It has been shown to improve the function of T-cells and B-cells, and its benefits for the immune system are especially well-documented in elderly populations.
Situational effect
Bromelain
Botanical
Impact
Situational effect
Typical dose:500–1000 mg / day
An enzyme complex derived from pineapple, bromelain has potent anti-inflammatory and mucolytic properties. It works by breaking down fibrin and reducing swelling in the nasal passages, providing tangible relief from sinus pressure and improving breathing.
Caprylic Acid
Fatty Acid
Impact
Situational effect
Typical dose:350–1000 mg / day
A significant portion of the immune system resides in the gut. Caprylic acid's main role is in controlling opportunistic fungi like Candida. For individuals whose immune system is burdened by gut dysbiosis, it can be situationally beneficial, but it is not a direct, general immune booster.
Curcumin
Botanical
Impact
Situational effect
Typical dose:500–1500 mg / day
Curcumin, the active compound in turmeric, is a potent modulator of inflammatory pathways like NF-kB. However, standard curcumin is very poorly absorbed. For immune benefits, it must be combined with a bioavailability enhancer like piperine (black pepper extract) or formulated as a phytosome.
Ginger
Botanical
Impact
Situational effect
Typical dose:500–2000 mg / day
The active compounds in ginger, such as gingerol, are effective at settling the stomach and reducing feelings of nausea. Additionally, ginger has been shown to have direct antimicrobial effects and can help modulate inflammation, making it a soothing and supportive herb during sickness.
Iron
Mineral
Impact
Situational effect
Iron is essential for the growth and differentiation of immune cells, and deficiency (anemia) is clearly linked to increased susceptibility to infection. However, pathogens also require iron to multiply, so supplementation should only be considered when a clinical deficiency is confirmed.
Lysine
Amino Acid
Impact
Situational effect
Typical dose:1000–3000 mg / day
Lysine competes with arginine, an amino acid that the herpes virus requires to replicate. By increasing the lysine-to-arginine ratio, supplementation can reduce the frequency, duration, and severity of cold sore outbreaks. Its use is specific to this condition, not general immunity.
Melatonin
Other
Impact
Situational effect
Typical dose:0.5–5 mg / day
Beyond regulating sleep-wake cycles, melatonin has direct immunomodulatory effects. It can reduce the excessive inflammation and oxidative stress seen in severe infections (e.g., cytokine storm), making it a valuable tool for managing the body's response during illness.
Resveratrol
Botanical
Impact
Situational effect
Resveratrol can influence various immune cell functions and is primarily beneficial for balancing the immune response to prevent excessive inflammation. Its role is more supportive and regulatory than being a primary agent for fighting off an active pathogen.
Limited evidence
Conjugated Linoleic Acid
Fatty Acid
Impact
Limited evidence
Typical dose:3.2–6.4 grams / day
While some research suggests CLA can influence inflammatory markers in specific contexts, it lacks robust clinical evidence for general immune support or acute infection response. Its effects are not consistently demonstrated and are considered speculative for this purpose.