Immune System Strengthening

Synopsis:
Background
Nutrients for Supporting Immune System
Suggested Supplementation
References

 

Age, stress, and poor nutrition can sap our immune system of its effectiveness. Influenza provides one example; during young adulthood, when the body can mount a robust immune response to this common virus, influenza is rarely fatal. Among the elderly, however, the virus is associated wigth significant rates of death and hospitalization (Nichol 2005).

The impact of aging on the immune system is profound. As people age, a number of critical immune system components including cellular response, antibody production, and response to vaccines are reduced or slowed. At the same time, susceptibility to infection and cancer is increased. Some of this increased susceptibility to disease is linked to chronic inflammation, which is associated with many disorders of aging (Ershler 2000; Hamerman 1999; Taaffe 2000).

Age, however, is not the sole culprit in reduced immune function. There is no question that exercise, stress, and nutritional status play an important role in maintaining a healthy immune system.

We believe that all aging people should take action to bolster their immune systems. This includes reducing negative psychological stress, exercising regularly, and eating a healthy diet as well as consuming nutrients that have been shown to enhance immune response and promote health.

 

The Immune System: How it Works

The immune system is an elegant and complex set of components that combine to fight disease, infection(s), and various pathogens. A healthy immune system distinguishes organisms in the body as “self” or “non-self.” An intact immune response identifies pathogens as “non-self” and rapidly destroys them. A depressed immune system, by contrast, will allow invading organisms to flourish.

When the immune system mistakenly recognizes a “self” cell as “non-self” and mounts an immune response, it can result in an autoimmune disorder (eg, rheumatoid arthritis).

In general, the body has two primary defense mechanisms: natural immunity and acquired immunity. Natural immunity is the “first responder” to attack. Natural immune response relies on various white blood cells and physical barriers to block or immediately attack any foreign invader and attempt to destroy it.

Acquired immunity, on the other hand, involves antibodies created in response to specific foreign antigens. This sort of response requires a few days for the body to recognize the invader and manufacture antibodies against it. Once the body has manufactured a particular antibody for a specific invader, the immune system response is faster and more effective the next time that invader appears (Janeway 1999; Beers 2004).

The natural immune system relies on a host of weapons to protect the body, including various kinds of white blood cells (see Table 1). These natural defenses include the following organs, chemicals, and processes:

Physical and chemical barriers: The body's first lines of defense are the skin and mucous membranes, which prevent the entrance of many pathogens. There are also many secondary barriers. For example, tears, sweat, and saliva combat some bacteria; also, the hydrochloric acid as well as protein-digesting enzymes secreted by the stomach are lethal to many, but not all pathogens (Janeway 1999; Beers 2004).

Inflammation and fever: Inflammation is a nonspecific response to infection or tissue injury. The four signs of inflammatory response are redness, swelling, heat, and pain. Inflammation begins when cells release certain cytokines, including interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) (Janeway 1999; Beers 2004).

 

Inflammation, Free Radicals, and Cytokines

Although acute inflammation is an important immune system response, chronic inflammation has also been linked to many diseases, including heart disease. Besides being associated with pro-inflammatory cytokines, inflammation may be related to the overproduction of free radicals (Janeway 1999), which are unstable and can cause damage to the body.

At high concentrations, free radicals can damage fats, proteins, and nucleic acids. They can also cause cell death, gene mutations, and cancer (Moslen 1994). Several diseases may be the result of cellular and genetic damage caused by free radicals, including several immune disorders (Moslen 1994).

In order to reduce the damage caused by elevated free radicals and cytokines (both part of the natural immune system), the body fights back by producing antioxidants and hormones (eg, cortisol) to suppress the immune system (Grimble 1996). Antioxidants are valuable because they pair with unstable free radicals, thereby limiting the damage free radicals can inflict on other cells.

 

Nutrition, Immunity, and Your Genes

Researchers are just beginning to understand how genes affect nutrition and overall immunity.

The association between diet and chronic diseases such as atherosclerosis, diabetes, obesity, and cancer is well known (Jenkins 1997; Jenkins 1999; Jenkins 2000; Kaput 2004). Nutrients supplied by food are an important variable in gene expression. Deficiency of some essential nutrients can alter metabolism and the structure of DNA (Kaput 2004). A well-studied example of the relationship between genetics and diet is type 2 diabetes. This condition is associated with a sedentary lifestyle, being overweight, and ethnicity. Although some individuals are genetically predisposed to this condition, many can control symptoms through exercise and a change in diet (Kaput 2004).

In the future, genetic testing might be able to help in the creation of nutritional programs tailored to each individual's genetic makeup; thus, may help people fight disease and stay healthy.

 

 

A healthy immune system grows ever more important as we age, and immune status is closely associated with nutrition, exercise, and stress reduction.

Vitamin D

Adults (and children) with higher vitamin D levels contract substantially fewer cold, flu, and other viral infections (Ginde 2009; Karatekin 2007; Cannell 2006). Vitamin D downregulates the expression of pro-inflammatory cytokines while upregulating the expression of antimicrobial peptides in immune cells (Schauber 2007). This biological mechanism explains why Vitamin D confers such dramatic protection against common illnesses.

Glutathione boosters

Glutathione is probably the body's most important cellular defense against free radical damage. It is a free radical scavenger and major antioxidant.

Low levels of glutathione are linked to many diseases. Malnutrition and aging (Cai 2000) deplete glutathione. Glutathione is also involved in one of the major liver detoxification pathways.

Glutathione is produced in the body, but not easily absorbed when taken orally. Instead, glutathione precursors may be used by the body to increase glutathione (Bounous 2000). Glutathione precursors include glutamine and S-adenosyl-L-methionine (SAMe) (Devlin 2002). It can also be upregulated by lipoic acid as well as vitamins C and E.

Glutamine

Glutamine is the most abundant amino acid in the body (Roth 2002). Glutamine depletion causes downregulation of glutathione levels in the body (Roth 2002), and dietary supplementation increases these levels (Roth 2002). Glutamine has immunoregulative activities (Roth 2002; Li 1995). Lymphocytes and macrophages use glutamine at a very high rate (Newsholme 1994). Glutamine stimulates lymphocyte production and killer immune cell activity (Rohde 1995, 1998, 1996; Jurectic 1994).

Glutamine depletion slows wound healing and increases the risk of organ failure under certain conditions (Wilmore 1991). Endurance athletes whose muscles do not fully recover between workouts have decreased glutamine levels (Shephard 1998; Castell 1998). Some scientists believe that intense physical exercise or stress due to trauma, burns, or sepsis (blood infection) forces the body into glutamine debt, which temporarily compromises immune function (Newsholme 1994).

S-adenosyl-L-methionine (SAMe)

S-adenosyl-L-methionine (SAMe) is a natural amino acid present throughout the body. It is crucially important because it is involved in dozens of chemical reactions, including the synthesis of DNA and RNA, proteins, melatonin, creatine, and many others. SAMe is an important energy source (Osman 1993) and intrinsically related to the synthesis of glutathione.

Antioxidants and Coenzyme Q10

Because of their ability to scavenge free radicals, antioxidants are important immune-system boosters. Supplementation with antioxidants like vitamins C, E, and B vitamins may improve immune function (Grimble 1997), and supplementation with vitamin A stimulates antibody-mediated immune responses (Cantorna 1995).

Vitamin E is a powerful fat-soluble antioxidant. It protects cellular membranes of the immune system and other cells by trapping free radicals, and enhances the effectiveness of lymphocytes (Kaminogawa 2004).

Vitamin C (ascorbic acid) is a key component of the immune system and antioxidant defense (Kagan 1991, 1992; Peters 1993). It prevents the production of free radicals and reduces DNA damage in immune cells. Moreover, vitamin C downregulates the production of pro-inflammatory cytokines and participates in recycling vitamin E (Schwager 1998).

B vitamins indirectly contribute to antioxidant defenses and have considerable influence on immune function. Vitamins B12 and B6 are cofactors in the creation of cysteine, a key component in glutathione synthesis. Deficiencies in B vitamins and vitamin E create abnormalities in immune response (Murrary 2000).

Lipoic acid is a potent antioxidant with antiviral, free-radical-quenching, and immune-boosting qualities. It is unusual because it is soluble in both fat and water (Kagan 1992), and is active in both its oxidized and reduced forms (Bustamante 1998). Lipoic acid is able to regenerate other antioxidants (eg, vitamins C and E) and raise glutathione levels significantly (Packer 1995, 1997; Scholich 1989; Fuchs 1993).

Coenzyme Q10 (CoQ10), synthesized from the amino acid tyrosine, is present in high quantities in the heart muscle. CoQ10 has shown a wide range of benefits. It is an essential cofactor in the production of adenosine triphosphate (ATP), which is the primary source of energy for all the body's cells. Levels of CoQ10 decline naturally as humans age, which may be related to increased lipid peroxidation. CoQ10 is a powerful antioxidant and scavenger of free radicals. It inhibits lipid peroxidation and works synergistically with vitamin E (Alleva 1995). CoQ10 has an important role in the stimulation of the immune system and improves several parameters of immune function (Folkers 1985).

Whey protein

Whey protein is isolated from milk. Proteins in whey are highly available to the body, and whey protein contains potent antioxidants. Its antioxidant activity is due to its high concentrations of glutamate and cysteine, which are precursors to glutathione (Walzem 2002). Whey also contains several substances that enhance the immune system, including the following:

• Beta-lactoglobulin, which modulates lymphatic responses (Guimont 1997)
• Alpha-lactalbumin, which has a direct effect on B and T lymphocytes and has the ability to reduce oxidative stress
• Lactoperoxidase, which reduces toxic hydrogen peroxide (Sundberg 1991; Ha 2003)

Lactoferrin, a major component of whey protein, also acts as an antioxidant (Steijns 2000). It can inhibit the absorption of bacteria through the intestinal wall. Whey protein can activate natural killer cells (Nishiya 1982). In the laboratory, lactoferrin inhibited metastasis of cancer cells in mice (Marshall 2004) and increased IL-2 and natural killer activity (Watanabe 2000).

Minerals

Metallic micronutrients such as copper, zinc (Prasad 2000), and selenium influence the activity of antioxidant enzymes and can reduce oxidative stress. Among children, deficiencies of zinc, copper, and selenium have been linked to immune deficiency and infection (Cunningham-Rundles 2005).

Selenium is involved in several key metabolic pathways (Rotruck 1973; McKenzie 1998, 2000). Glutathione peroxidase, the enzyme that recycles glutathione, depends on the presence of selenium for its antioxidant activity (Arthur 2003). Although plant food is a major dietary source of selenium (eg, garlic is rich in selenium), the highest concentration of dietary selenium occurs in meat.

Zinc deficiency is linked to impaired immune function, partly because of decreased T lymphocyte and B lymphocyte function. Zinc has shown the ability to decrease inflammation and the production of IL-2 (Tanaka 2005). Copper and zinc together have been shown to stimulate internally produced antioxidants such as glutathione and superoxide dismutase (SOD) (Kuppusamy 2005).

Polyunsaturated Fatty Acids

Polyunsaturated fatty acids, such as the omega-3 fatty acids found in fish oil and flaxseed oil, have been studied for their anti-inflammatory action (Kaminogawa 2004). Polyunsaturated fatty acid reduces the inflammatory response caused by TNF-α (Johnson 1993; Pedersen 2000).

Omega-3 fatty acids have also been shown to:

• Counteract suppression of the cellular immune system (Pedersen 2000)
• Suppress TNF-α production and have an anti-inflammatory effect (Grimble 2002)

Probiotics

The gastrointestinal tract relies on live bacteria (microflora) to help support a robust immune response. These probiotic bacteria help prevent foreign bacteria and allergens from passing through the intestinal wall and are important to the overall health of the intestinal immune system (Marteau 2001; Conway 1987; Robins-Brown 1981). Probiotics are found in foods such as yogurt and kefir, which enhance the microflora in the gut by providing additional probiotic bacteria (Fuller 1991; Isolauri 2001). The most commonly used probiotic bacteria are lactobacillus and bifidobacterium, found in yogurts.

Probiotics also strengthen the intestinal immunological barrier. Lactobacillus stimulates natural immunity by improving phagocytic and natural killer immune cell activity (Kaminogawa 2004).

Grape Seed Extract

Chemicals in grape seeds known as proanthocyanidins have potent antioxidant and immune-boosting properties (Ashraf-Khorassani 2004; Bagchi 1997; Bagchi 1998). They increase the activity of internal antioxidants such as glutathione and SOD (Peng 2000).

The antioxidants in grape seed extract are twice as potent as vitamin E and four times as potent as vitamin C (Bagchi 1997; Bagchi 1998). In laboratory studies, proanthocyanidins increased the power of natural killer cells, enhanced the production of IL-2, and decreased production of IL-6 (Cheshier 1996).

Green Tea Extract

Green tea extract, which contains a class of compounds known as catechins, has become increasingly popular as scientists learn more about its antioxidant and free radical–scavenging abilities. One of the most potent catechins in green tea is epigallocatechin-3-gallate (Chen 2002). Green tea extract is also rich in vitamins C and B (Hasegawa 2002; Hasegawa 1998).

Green tea has a positive influence on lipid metabolism and exerts anticancer effects. Green tea modulates the inflammatory processes and protects against DNA damage (Lin 1998). The catechins from green tea demonstrate considerable antioxidant activity (Chen 2002) and are potent free radical scavengers (Zhong 2003; Jimenez-Lopez 2004).

Andrographis

Healers in Asia and India have long prescribed the bitter herb Andrographis paniculata for the treatment of ailments ranging from infections and inflammation to colds and fevers (Ji 2005). Researchers have isolated a number of the herb’s active ingredients. Chief among these are andrographolides, which are phytochemicals believed to exert their effects, in part, on tissues of the blood cell-producing bone marrow and/or spleen. One such compound, andrographanin, enhances the ability of certain white blood cells to recognize and neutralize foreign cells (eg, tumor cells and viruses) (Ji 2005).

Beta Glucan

Beta glucans can naturally boost the immune system by optimizing its response to diseases and infections. Because the body does not produce beta glucans naturally, the only way to get them is through outside sources. Studies have shown that beta glucans act as immunomodulator agents, meaning they trigger a cascade of events that help regulate the immune system, making it more efficient. Specifically, beta glucans stimulate the activity of macrophages, which are versatile immune cells that ingest and demolish invading pathogens and stimulate other immune cells to attack (National Institute of Allergy and Infectious Diseases 2012). Macrophages also release cytokines, chemicals that when secreted enable immune cells to communicate with one another. In addition, beta glucans stimulate lethal white blood cells (lymphocytes) that bind to tumors or viruses, and release chemicals to destroy it.

 

 

• Comprehensive multivitamin: Per label instructions
• Selenium: 200 – 400 mcg daily
• Zinc: 30 – 90 mg daily
• Vitamin D: 5000 – 8000 IU daily (depending upon blood levels of 25-OH-vitamin D)
• Vitamin C: 1000 – 5000 mg daily
• Garlic extract: 1200 mg daily
• Andrographis Extract: 25 – 150 mg daily 30 minutes before a meal
• Beta Glucan: (highly purified Beta 1,3/1,6 Glucan): 100 – 600 mg daily 30 minutes before a meal
• Whey protein isolate: 20 – 40 grams daily
• CoQ10: 100 – 200 mg daily (Ubiquinol form of CoQ10)
• Lactoferrin (apolactoferrin): 300 mg daily
• Probiotics: Per label instructions
• Fish oil (with olive polyphenols): providing 1400 mg EPA and 1000 mg DHA daily
• Grape extract (containing seed and skin extracts): 150 mg daily
• Green tea extract (standardized to 98% polyphenols): 725 mg daily
• R-lipoic acid: 300 – 600 mg daily

 

 

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