4 Science-Backed Ingredients To Boost The Immune System

4 Science-Backed Ingredients To Support The Immune System

In addition to your general diet and lifestyle, there are certain nutrients and minerals that may be beneficial to take as supplements, which have been shown to have supportive effects on your immune function. Here we take a look at four of our science-backed ingredients to support healthy immune system function.

IMUNI Immune Defence is a unique formulation designed to maintain healthy immune system function and support the immune system to fight illness. Containing antioxidants that help reduce free radical damage to body cells and helps maintain optimal vitamin D and zinc levels in the body. 

Quercetin is a well-known antioxidant and an abundant ‘flavonoid’ found in several foods derived from plants. Flavonoids are natural compounds obtained in the human diet from the ingestion of plant products, that have been widely recognised for their antioxidant properties discovered more than 40 years ago. Quercetin is the most abundant flavonoid in the human diet and is derived from plant-based food products including onions, apples, blueberries, kale, broccoli, tea and red wine. Scientific evidence has demonstrated Quercetin’s physiological properties for a range of mechanisms, including antioxidant effects. Quercetin’s antioxidant activity means that it can help reduce free radical damage to body cells, as well as helping to maintain immune system health and function.

Zinc is an essential micronutrient which plays a role in the regulation of immunity, including the normal development and function of cells involved in healthy immune system function.

Zinc deficiency can result in impaired immune system function and has been recognised as relatively common in low to middle income countries. An Australian sample of 497 Tasmanian adults also demonstrated that zinc deficiency was particularly prevalent in older men with 18% of men over the age of 50 and 30% of men over the age of 70 considered to have suboptimal zinc status. The 2011-2012 National Nutrition and Physical Activity Survey conducted by the Australian Bureau of Statistics found that more than one third of Australian adult men (aged 19+) had inadequate zinc intake below the Estimated Average Requirement (EAR). Inadequate dietary zinc intake was found to be less common in Australian women, with between 7.8% and 13.5% of adult women found to have inadequate zinc intake.

It is important to note that excessive zinc intake can increase the risk of adverse effects, including acute symptoms such as nausea, as well as chronic adverse health effects. Zinc intakes above 150mg per day have been associated with copper and iron deficiencies as well as reduced immune system function. 40mg of elemental zinc is equivalent to the Upper Level of intake (UL) as defined by the National Health and Medical Research Council (NHMRC). Higher amounts can increase the risk of adverse effects.

Vitamin C, also known as ‘ascorbic acid’ or ‘ascorbate’, has long been recognised for its important role supporting healthy immune system function as well as its antioxidant properties, protecting against oxidative stress and free radical damage to body cells. It is likely that all of the biochemical and molecular functions of vitamin C relate to its antioxidant properties. Interestingly, research also suggests that co-administration of vitamin C with Quercetin exerts a synergistic action due to the capacity of vitamin C to recycle Quercetin into its active form, potentially increasing its bioavailability and antioxidant activity.

According to some scientific research, blood plasma concentrations of vitamin C tend to increase with doses of up to 1000mg per day, with doses above this level tending not to significantly influence plasma levels. For those people with adequate intakes (i.e. near ‘steady state’ plasma concentrations), 200mg of vitamin C per day tends to achieve plateau concentrations in the blood, meaning that higher amounts are likely to saturate blood levels and excess vitamin C will be excreted in the urine. Additionally, absorption characteristics are such that smaller doses of vitamin C (e.g. 250mg per day) are more completely absorbed than larger single doses, suggesting that taking smaller doses more than once per day might be more beneficial in terms of bioavailability. While an Upper Level of intake (UL) has not been established, expert bodies recommend adults should take no more than 1000mg per day to minimise the risk of adverse effects.

Vitamin D3 - Maintaining optimal levels of vitamin D may assist in supporting general health and wellbeing, including immune system health. Vitamin D plays an important role in the immune response as an immune modulator. Vitamin D receptors have been identified on various immune cells including macrophages, monocytes, dendritic cells, and T and B lymphocytes.

Vitamin D deficiency is relatively common with nearly a third of Australians over the age of 25 shown to have low levels of vitamin D. This finding was demonstrated in a large population-based study conducted in 2012 which assessed vitamin D levels in more than 11,000 Australians. Vitamin D deficiency was found to affect 31% of Australians, with the highest incidence in women (39% were deficient in vitamin D overall). The study also found that nearly sixty percent of women were found to be deficient in vitamin D over the period of winter to spring, and 73% of Australians had vitamin D levels less than 75 nmol/L - the level classified as ‘vitamin D insufficiency’.

There are many plausible reasons to explain why such large proportions of the population are afflicted by suboptimal vitamin D status including:

  • Greater amount of time spent indoors at work and home
  • Increased adherence to sun protection (SPF 15+ sunscreen blocks 99% of vitamin D synthesis in the skin)
  • Higher proportion of people adhering to plant-based diets (vitamin D levels are higher in animal products overall)
  • Lower levels of vitamin D in conventional diets (mushrooms for example are typically grown in dark growing rooms precluding exposure to sunlight which is essential for vitamin D synthesis)
  • A growing elderly and institutionalised population with lower exposure to sunlight
  • Rising rates of obesity are also likely to be partially responsible for suboptimal vitamin D status

The safest way to optimise your vitamin D level is to consider seeing your GP for a blood test and to supplement accordingly to attain levels of 100 nmol/L (this is the suggested general target for optimal beneficial effects of vitamin D). In general, the total daily requirement of vitamin D (from sunlight and diet combined) is around 4000 IU to maintain levels above 100 nmol/L. Evidence suggests that excessive exposure to the sun to obtain these levels may increase skin cancer risk, and therefore dietary supplementation may be beneficial. In Australia, the maximum daily dose of vitamin D recommended for general use is 1000IU per day unless advised otherwise by your doctor.


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