As people age, the immune system begins a process of restructuring and immune organs begin to slow, reducing their ability to fully function as they go through physiological involution. Innate immunity is a non-specific system including physical barriers such as skin, stomach acid, and mucosal membranes.

The result is an overall reduced ability for immune cells to recognize antigenic variation, diminishing the ability of the immune system to recognize and fight pathogens. Aging in the immune system also corresponds with an increased secretion of cytokines (the immune system’s chemical messengers) and a reduction in macrophages and natural killer cells. (Macrophages are white blood cells that kill invading pathogenic microorganisms, remove dead cells, stimulate immunity and tissue repair, and produce inflammatory and antimicrobial compounds.)

This cascade of changes causes “inflammaging”—a chronic, low-grade inflammation associated with senescence. Inflammaging occurs throughout the tissues and organs, disrupting the gut microbiota. Since the digestive system is the most important immune system in the body, this can lead directly to a gradual weakening of immune function.

Microbial diversity in the gut decreases with age, which is partially associated with dietary changes and restrictions along with the shifts in innate immune function previously described. As the gut microbiome changes, the body can enter a state of dysbiosis. However, enriching the diet with regimens of prebiotics, probiotics, postbiotics, and other ingredients can establish greater microbial diversity in the gut and has been reported to improve immune function in the aging population.

Rebuilding the system

Dietary fiber is important not only as a prebiotic compound, but also for immune health in seniors. Oligosaccharides, pectin, and inulin have been reported to improve epithelial cell barrier integrity among other improvements to innate immunity and gut health.

Reduced fiber consumption in the diet reduces microbial diversity in the gut and can increase incidence of inflammation and pathogen establishment. Oligosaccharides have been linked to benefits in the innate immune system, including improvements in atopic dermatitis as well as anti-allergenic and anti-inflammatory effects.

Oligosaccharides, specifically fructo-oligosaccharides and galacto-oligosaccharides, have an immunomodulatory effect, beginning with a prebiotic impact on the gut microbiome. Fructans such as inulin also have an immunomodulatory effect, stemming from reinforcing the gut microbiome as a prebiotic fiber.

Not only do these compounds provide a nutrient source for gut microbes, but also when they are paired with probiotics such as Bifidobacterium and Lactobacillus species, gut dysbiosis diminishes and epithelial integrity improves. Fructans and fructo-oligosaccharides are available from a variety of food ingredients, including artichokes, garlic, bananas, onions, and other produce.

Galacto-oligosaccharides are found in most legumes and other foods such as cashews. While these foods contain effective prebiotics, there are other products—such as postbiotics—that aid in boosting the immune system and mitigating the impact of immunosenescence.

Beyond biotics

Antioxidants are known to help alleviate health concerns such as high blood pressure, inflammation, high cholesterol, and even to reduce symptoms of diabetes, anxiety, and depression. Not only are antioxidants a postbiotic compound produced by healthy gut microbes, they can be added to the diet in the form of common vitamins.

Chia seeds are a great source of antioxidants, polyunsaturated fatty acids, and amino acids. Quercetin phenolic glycosides and kaempferol phenolic glycosides are two flavonols found in high concentrations in chia seeds that not only have an antioxidative effect, but also provide anti-inflammatory, antimicrobial, anti-Alzheimer’s, anti-arthritic, and anticancer properties.

Quercetin, specifically, has a higher bioavailability than many other phytochemicals. This impressive phenolic compound is available from fruits (especially red and purple fruits and vegetables, including berries, tomatoes, and red onions), kale, red wine, and black tea.

Quercetin has a positive impact on cardiovascular health by inhibiting angiotensin-converting enzyme activity and improving the hypertensive response to angiotensin. It also has anti-inflammatory, antihypertensive, and vasodilator effects. These are mediated by quercetin’s ability to scavenge free radicals and oxidative compounds.

While oxidative compounds are important in the destruction of pathogens, there are multiple pathways in the body that contribute to overproduction of these compounds. This not only increases the rate of aging but also can ultimately be detrimental to organ systems and overall health.

Quercetin taken in combination with zinc can have a synergistic effect, improving zinc uptake while boosting the activity of quercetin. While both men and women should consider a quercetin supplement, NIH surveys and other studies indicate that men eat less produce than do women, therefore men tend to consume fewer quercetin-containing ingredients in their diet overall. So, it could be more beneficial for men to supplement their diet accordingly.

Taking heart

Adult men also should consider increasing their intake of CoQ-10. Also known as “ubiquinone,” CoQ-10 is a co-vitamin and powerful antioxidant. It indirectly mediates immune function by regulating cell metabolism and removing free radicals from cells. While CoQ-10 is endogenously produced, that production begins to decrease as early as age 35 and by age 50, supplementation can be beneficial to reduce vascular oxidative stress. It also helps to improve mood and energy levels in the elderly.

While senior men and women can benefit from CoQ-10 supplementation, men are particularly susceptible to depleted levels of CoQ-10. Additionally, men tend to exhibit greater incidence of cardiovascular disease compared with women. Endogenous CoQ-10 production is disrupted when statin drugs are prescribed to alleviate the symptoms of cardiovascular diseases. This is especially critical in that CoQ-10 not only functions as an antioxidant, but it also is necessary for the regulation of heart function, vascular elasticity, and cellular energy production.

CoQ-10 can be found in a variety of food ingredients, including meat, poultry, and seafood; legumes; certain fruits and vegetables; and nuts and seeds. These foods also are good sources of the tocopherol form of vitamin E, a powerful antioxidant and an important component in the wound-healing process.

Another form of vitamin E, tocotrienol, is actually several hundred times more powerful an antioxidant than its “sister” tocopherol. Found in high concentrations in annatto, red palm oil, and rice bran oil, tocotrienol has been proven to improve cardiovascular health and reduce free radicals in the body.

Not only is vitamin E an essential vitamin, but tocotrienol and tocopherol alike are important nutrients in protecting against oxidative stress, neurodegeneration, and immune modulation.

Tocotrienol is most effective in the senior population as an aid to improved cognitive and cardiovascular function. It has been shown to reduce inflammation, arterial plaque formation, hypercholesterolemia, and the progression of osteoporosis, and alleviate the symptoms of Alzheimer’s disease and dementia. A number of studies also have demonstrated its ability to help induce apoptosis (cellular self-destruction) in cancer cells.

Bone and joint health

Post-menopausal women are at high risk for osteoporosis and are susceptible to severe bone breaks as a result. Although clinical studies continue to be conducted, there is promising evidence that tocotrienol supplementation helps regulate bone growth and bone cell turnover. Furthermore, studies of tocotrienol’s purported anticancer capacity include research that supports the improvement by 60% of the 5-year breast cancer specific survival rate.

Hydrolyzed collagen is an ingredient capable of reducing inflammation, improving symptoms of osteoporosis and promoting cartilage repair in damaged joints. Absorption of hydrolyzed collagen is greater than that of non-hydrolyzed collagen. Once absorbed, the amino acids and peptides from the hydrolyzed collagen stimulate both the nervous and immune systems.

This helps inhibit inflammation in articular cartilage in joint tissue and reduces the function of the osteoclast cells that break down bone. Hydrolyzed collagen can contain different amino acid profiles, which have different biological impacts on the body. This can lead to mixed results among the research studies comparing hydrolyzed collagen products.

While further research is needed, there is evidence supporting joint pain relief and improvement of articular cartilage in patients with osteoarthritis. In addition to osteoporosis, women are at higher risk than men for osteoarthritis.

Supplementation with hydrolyzed collagen could be beneficial to immune support of cartilage and bones. Studies pairing hydrolyzed collagen with glucosamine suggest the combination helps alleviate joint pain and improve joint function in as short a time as 90 days.

There is consistent evidence that hydrolyzed collagen also improves skin hydration, elasticity, and firmness while reducing the appearance of wrinkles. Bone and joint-supporting minerals such as calcium, potassium, phosphorus, iron, and zinc, as well as vitamin C also are needed for building and maintaining skin elasticity and structure. Combining hydrolyzed collagen with these ingredients can add a “beauty from within” component to a formulation targeting bone and joint support.

With the segment of persons over age 55 approaching 50% of the U.S. population, the need for immune-supporting foods and beverages targeting their demographic will only become more urgent. This also translates to greater opportunities for the product developers creating these products for a more active, engaged senior population.

Botanical Intervention

While the most prominent category in immune-supporting foods is that of cultured dairy, botanical ingredients also have a role to play. Cultures that rely on traditional medicine practices, such as Ayurveda and Traditional Chinese medicine, have a record of using specific herbs, flowers, spices, fungi, bark, roots, and rhizomes for immune health that stretches back thousands of years. Botanical ingredients can figure prominently in product developers’ efforts to create new foods and beverages that help the body protect itself against disease and dysfunction. To learn more, check out “Botanicals for Immunity Are Growing,” an interview with ethnobotanist, herbalist, and author Kerry Hughes, principal for EthnoPharm. View the video of the interview here, or listen to the podcast, here. You’ll find more videos, podcasts, and articles on botanicals for immunity from Ms. Hughes at www.preparedfoods.com. 

First Line of Defense

The skin doesn’t always receive fair recognition as an organ of immunity, but it is the first line of defense against exogenous assaults from the environment. However, as people age, dermal collagen degrades and the cells become less organized, leading to a cascading effect of slow degradation. The increased amino acid and peptide absorption in the intestine from consumption of hydrolyzed collagen accumulates not only in articular cartilage but also in the skin, forming new collagen fibers. This helps reduce the appearance of aging and improves the innate immune system by fortifying this important defensive barrier.

Ingredients for Seniors

Need a quick guide to important ingredients for supporting health and immunity in the over-55 set? Check out this infographic.