Vitamin C

Vitamin C and Immune Function
Vitamin C is an essential micronutrient for humans, with pleiotropic functions related to its ability to donate electrons. It is a potent antioxidant and a cofactor for a family of biosynthetic and gene regulatory enzymes. Vitamin C contributes to immune defense by supporting various cellular functions of both the innate and adaptive immune system. Vitamin C supports epithelial barrier function against pathogens and promotes the oxidant scavenging activity of the skin, thereby potentially protecting against environmental oxidative stress. Vitamin C accumulates in phagocytic cells, such as neutrophils, and can enhance chemotaxis, phagocytosis, generation of reactive oxygen species, and ultimately microbial killing. It is also needed for apoptosis and clearance of the spent neutrophils from sites of infection by macrophages, thereby decreasing necrosis/NETosis and potential tissue damage.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5707683/

Vitamin E

Role of Vitamin E in Immune System
Vitamin E, α-tocopherol,acts as an antioxidant in cellular membranes and as a free radical scavenger by blocking the peroxidation of polyunsaturated fatty acids (PUFA). The damage of cellular membrane induced by free radicals results in changes of membrane-related cellular functions, inducing in some cases, the destruction of cells. In immune cells, αtocopherol content is known to be higher than in other cells, because the cellular membrane plays animportant role in the immune response. This suggests that vitamin E is an important nutrient in maintaining normal immune functions.
https://www.jstage.jst.go.jp/article/jcbn1986/34/3/34_3_97/_pdf

Selenium

Selenium, Selenoproteins, and Immunity
Selenium is an essential micronutrient that plays a crucial role in development and a wide variety of physiological processes including effect immune responses. The immune system relies on adequate dietary selenium intake and this nutrient exerts its biological effects mostly through its incorporation into selenoproteins.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6163284/

Graviola

Immunomodulatory Efficacy of Standardized Annona muricata (Graviola) Leaf Extract via Activation of Mitogen-Activated Protein Kinase Pathways in RAW 264.7 Macrophages
Annona muricata L. is a medicinal plant, commonly known as Graviola, Soursop, or Guabana. Graviola is a tropical evergreen fruiting tree, which belongs to the Annonaceae family. All parts of the Graviola tree are known to be effective against various human diseases such as cancer and parasitic infections. In particular, Graviola leaves were found to be effective against cystitis, diabetes, headache, insomnia, and inflammation.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209628/

Red Raspberry

Red Raspberries and Their Bioactive Polyphenols: Cardiometabolic and Neuronal Health
Diet is an essential factor that affects the risk of modern-day metabolic diseases, including cardiovascular disease, diabetes mellitus, obesity, and Alzheimer disease. The potential ability of certain foods and their bioactive compounds to reverse or prevent the progression of the pathogenic processes that underlie these diseases has attracted research attention. Red raspberries (Rubus idaeus L.) are unique berries with a rich history and nutrient and bioactive composition. They possess several essential micronutrients, dietary fibers, and polyphenolic components, especially ellagitannins and anthocyanins, the latter of which give them their distinctive red coloring. In vitro and in vivo studies have revealed various mechanisms through which anthocyanins and ellagitannins (via ellagic acid or their urolithin metabolites) and red raspberry extracts (or the entire fruit) could reduce the risk of or reverse metabolically associated pathophysiologies.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4717884/#__sec5title

Green Tea

6 Foods to Boost Your Immune System
Whether you prefer green or black tea, your immune system is in luck. Both provide disease-fighting antioxidants (polyphenols and flavonoids) that protect against free radicals and help destroy them. One study showed that catechins, a particular type of polyphenols in tea, kill certain viruses. Another Harvard study showed that people who drank 5 cups a day of black tea for two weeks had 10 times more virus-fighting interferon in their blood than other who drank a placebo hot drink. Both black tea and green tea are rich in L-theanine, an amino acid thought to help enhance immunity that’s found in both regular and decaf versions.
https://www.foxnews.com/health/6-foods-to-boost-your-immune-system

Beta-Glucan

Effects of beta-glucans on the immune system
Beta-glucans are naturally occurring polysaccharides. These glucose polymers are constituents of the cell wall of certain pathogenic bacteria and fungi. The healing and immunostimulating properties of mushrooms have been known for thousands of years in the Eastern countries. These mushrooms contain biologically active polysaccharides that mostly belong to group of beta-glucans. These substances increase host immune defense by activating complement system, enhancing macrophages and natural killer cell function.
https://www.ncbi.nlm.nih.gov/pubmed/17895634

Turmeric

"Spicing up" of the immune system by curcumin
Curcumin (diferuloylmethane) is an orange-yellow component of turmeric (Curcuma longa), a spice often found in curry powder. Traditionally known for its an antiinflammatory effects, curcumin has been shown in the last two decades to be a potent immunomodulatory agent that can modulate the activation of T cells, B cells, macrophages, neutrophils, natural killer cells, and dendritic cells. Curcumin can also downregulate the expression of various proinflammatory cytokines including TNF, IL-1, IL-2, IL-6, IL-8, IL-12, and chemokines, most likely through inactivation of the transcription factor NF-kappaB. Interestingly, however, curcumin at low doses can also enhance antibody responses. This suggests that curcumin's reported beneficial effects in arthritis, allergy, asthma, atherosclerosis, heart disease, Alzheimer's disease, diabetes, and cancer might be due in part to its ability to modulate the immune system. Together, these findings warrant further consideration of curcumin as a therapy for immune disorders.
https://www.ncbi.nlm.nih.gov/pubmed/17211725

Pine Bark

Pycnogenol attenuates the symptoms of immune dysfunction through restoring a cellular antioxidant status in low micronutrient-induced immune deficient mice
Pycnogenol (Pyc), a standardized extract from the French maritime pine bark (Pinus pinaster Ait.), consists of a concentrate of polyphenols whose main constituents are procyanidins, pharmacologically active biopolymers composed of units of catechin and epicatechin. In addition, Pyc contains the bioflavonoids catechin and taxifolin and a number of phenolic acids [4]. Pyc is known to exhibit efficient antioxidant activity and it may act as a modulator of metabolic and antioxidant enzymes and other cellular functions ... study suggest that Pyc supplementation ameliorates premature death by restoring immune dysfunction, such as increasing lymphocyte proliferation and regulation of cytokine release from helper T cells, which may result from the antioxidative ability of Pyc.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4198966/

Essiac Tea

ESSIAC, "TEA OF LIFE?”
Essiac is a combination of four principle herbs-. burdock root, turkey rhubarb root (or Indian rhubarb), sheep sorrel, and slippery elm bark . Burdock has been found to produce "considerable antitumor activity"...and reduction of cell mutation. It also "stimulates bile production and helps liver functions, and is used as a tonic, blood pufifier, and cleanser." Turkey rhubarb root "is a laxative and astringent; it is an effective tonic for the digestive system and acts upon the bowels, removing debris and tightening the tissues. Sheep sorrel is known to sharpen the appetite, assuage heat, cool the liver, and strengthen the heart. Slippery elm is known as a stomach remedy and wound healer; it is healing to the mucous membrane of the entire digestive tract.
http://healthpsych.psy.vanderbilt.edu/HealthPsych/essiac.htm

Grape Seed

Relevance of Natural Phenolics from Grape and Derivative Products in the Formulation of Cosmetics
The antioxidant properties of grape parts, products and byproducts is well known, including their chelating activities, high radical scavenging properties in relation to Trolox and Vitamins C and E and the potential to inhibit lipid oxidation in various food and cell models. The consumption of grape-derived dietary flavonoids in the form of grape extracts and grape seed powders has been shown to effectively suppress oxidative stress and prevent oxidative damage in vivo.
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.699.1388&rep=rep1&type=pdf

Mushroom Complex

Edible Mushrooms: Improving Human Health and Promoting Quality Life
A large variety of mushrooms have been utilized traditionally in many different cultures for the maintenance of health, as well as in the prevention and treatment of diseases through their immunomodulatory and antineoplastic properties. In the last decade, the interest for pharmaceutical potential of mushrooms has been increased rapidly, and it has been suggested that many mushrooms are like mini-pharmaceutical factories producing compounds with miraculous biological properties. In addition, the expanded knowledge of the molecular basis of tumorigenesis and metastasis has given the opportunity for discovering new drugs against abnormal molecular and biochemical signals leading to cancer ... they are recognized as potent immunological stimulators in humans, and it has been demonstrated their capacity for treating several diseases. 𝛽-glucans bind to a membrane receptor and induce these biological responses. Natural products with fungal 𝛽-glucans have been consumed for thousands of years and they have long been considered to improve general health [48]. 𝛽-glucans are not synthesized by humans and they are not recognized by human immune systems as self-molecules; as a result they induce both innate and adaptive immune responses. Fungal 𝛽-glucans are notably beneficial to humans; they markedly stimulate the human immune system and protect from pathogenic microbes and from harmful effects of environmental toxins and carcinogens that impaired immune systems.
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.787.8502&rep=rep1&type=pdf

Quercetin Dihydrate

Quercetin: 8 Proven Benefits of This Antioxidant (#1 Is Incredible)
Quercetin is considered the most diffused and known nature-derived flavonol there is, showing strong effects on immunity and inflammation caused by leukocytes and other intracellular signals. Quercetin plays a role in regulating the immune system’s response to outside stressors through cell signaling pathways called kinases and phosphatases, two types of enzyme and membrane proteins needed for proper cellular function.
https://draxe.com/nutrition/quercetin/

Pomegranate

Nutritional and Therapeutic Properties of Pomegranate
Seeds of pomegranate contains low quantity of fats while high carbohydrate and protein content. According to an estimate ½ cup consist of 1 gram of fat, 16 grams carbohydrates and 1.5 grams proteins. 72 percent calories are provided by these components. It contains appreciable amount of vitamin C which is beneficial for blood clotting and immune system.
https://lupinepublishers.com/food-and-nutri-journal/fulltext/nutritional-and-therapeutic-properties-of-pomegranate.ID.000118.php

Olive Leaf

Phytochemical analysis and gastroprotective activity of an olive leaf extract
Olive leaf is used to enhance the immune system, as an antimicrobial and in heart disease. Folk medicine uses also include hypertonia, arteriosclerosis, rheumatism, gout, diabetes mellitus, and fever.
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.429.7897&rep=rep1&type=pdf

Cat’s Claw

Cat’s Claw (Uncaria tomentosa)
Scientific studies by the National Cancer Institute have verified both anticancer and immune stimulating properties of Cat's Claw. Cat’s Claw, like most plants, is extremely complex in its composition and is very rich in phytochemical actives. Research has uncovered a host of chemical components that may very well explain its folkloric uses. The active constituents that appear to be the most important are a group of alkaloids called oxindole alkaloids. These oxindoles include sopteropodine, pteropodine, isomitraphylline, rhynchophylline, isorynchophylline, and mytraphylline. Four of these components have been found to have profound immunostimulating properties.
https://www.huhs.edu/literature/Cat's%20Claw.pdf

Garlic

University of Rochester Medical Center Health Encyclopedia
Garlic contains allicin. This is a strong antibiotic. It’s released when cloves are crushed or chewed. Garlic has been used as an antiseptic, antibacterial, and antifungal agent. It may help the body resist or destroy viruses and other microorganisms. It does this by boosting the immune system.
https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Garlic

Panax Ginseng

Use of Ginseng in Medicine: Perspectives on CNS Disorders
Ginseng also has immunostimulant effects as it enhances interferon induction, phagocytosis, natural killer (NK) cell, and B and T cells in various animal species including mice and guinea pigs and also in humans.
http://www.bioline.org.br/pdf?pt04005

Lycopene

Lycopene-rich tomatoes linked to lower stroke risk
Researchers suggested that lycopene, in addition to its ability to attack free radicals, may also reduce inflammation and cholesterol, improve immune function, and prevent blood from clotting. All of these may help reduce ischemic strokes, which are caused by clot-caused blockages in blood flow to the brain.
https://www.health.harvard.edu/blog/lycopene-rich-tomatoes-linked-to-lower-stroke-risk-201210105400