Zinc is an essential trace element that functions in the body as a co-factor for several enzymes or as a structural element for a variety of proteins. It is well-known that zinc deficiency can result in growth retardation, delayed wound healing, and high incidence of infection; the latter points are due to its importance for the immune system. Zinc is crucial for the functioning of virtually all immune cells. For example, zinc is an essential component of thymulin, a thymic hormone involved in maturation and differentiation of T-cells. Zinc supplementation has been shown to promote regulatory T-cell development therefore having a positive effect on immune system. The fundamental elements of zinc for the immune system has been known since the 1960s and the corresponding mechanistic knowledge has been expanding ever since. Many studies have shown the importance of zinc in supporting and enhancing immune system. They have also demonstrated the importance of maintaining an adequate zinc status in elderly population. As we age, our immune system is more susceptible to weakening, which can lead to serious health problems. In order to limit this decline, it is essential to maintain healthy immunity through a diet rich in phytochemicals and essential nutrients. Consequently, maintaining an adequate zinc level in the body can limit the decline in immune function and reduce the risk of getting ill as we age.*
Echinacea - is probably the most common herbal supplement associated with the prevention and treatment of colds. This plant is promoted as an immune-system stimulant. There are three different species of Echinaceacurrently used for medicinal purposes: three species of Echinacea, namely E. purpurea, E. angustifolia and E. pallida, have been used in medicine for centuries for common cold and coughs. There are many studies that support these immunomodulatory effects. Anti-viral and anti-microbial effects have also been demonstrated, supporting its use in traditional medicine.
Echinacea preparations are extensively used for the management of the common cold. But despite its popularity, clinical studies on Echinacea have produced mixed results (possibly in part of the poor characterization of the extracts and the use of different species and/or plant parts used in the various trials). To address this issue, a study investigated a highly standardized Echinacea extract with a specific phytochemical profile to evaluate the effect of Echinacea in enhancing the immune response. The study was conducted among participants with respiratory ailments and determined whether alone or in combination with the influenza vaccine, echinacea extract could influence the occurrence of symptoms suggestive of influenza infections. Results from this study showed a statistically significant tendency for the Echinacea extract to be more efficacious that the vaccination alone. Some parameters of immune function were also positively altered. The authors also noted fewer respiratory complications when the echinacea preparation was given either alone or in combination with the vaccine. The authors concluded that with excellent tolerability of the extract, combined with positive preliminary results on immune function, echinacea extract could represent a potential clinical benefit and be used for improving the immune response to influenza vaccine.
Elderberry - Sambucus nigra, or European elderberry, is a tall tree-like shrub, native to Europe, Asia, and North Africa, and naturalized in the United States. Various parts of the elder have long been used in traditional medicine. The berries were used traditionally as a food to make elderberry wine and pies, and as a flavoring or dye. Currently, extracts of the berries are used primarily as antiviral agents for colds, influenza, and Herpes virus infection. Research has also demonstrated Sambucus nigra has immune-modulating, antioxidant, and insulin-stimulating properties.
A clinical study evaluated the safety (risk) and efficacy (benefit) of Echinacea purpurea extract in the prevention of common cold episodes in a large population over a 4-month period. More than seven hundred healthy subjects were allocated to rec
ive either an alcohol extract from freshly harvested E. purpurea (95% herbal and 5% root) or placebo.
Participants were required to rate cold-related issues in a diary throughout the investigation period. Nasal secretions were sampled at acute colds and screened for viruses. Based on the results, Echinacea reduced the total number of cold episodes, cumulated episode days within the group, and pain-killer medicated episodes. Echinacea inhibited virally confirmed colds and especially prevented enveloped virus infections (P < 0.05). Echinacea showed maximal effects on recurrent infections, and preventive effects increased with therapy compliance and adherence to the protocol. The authors concluded that compliant prophylactic intake of E. purpurea over a 4-month period appeared to provide a positive risk to benefit ratio.
