by Cliff Harvey PhD 

“Immunity” is a term that encompasses the specific immune responses to pathogens (like bacteria and viruses that make us sick) but most of us have a broader definition, which is simply how resilient we are to illness and infection.

When we look at immunity this way, we need to first understand the inter-related nature of the human body, its organs, tissues, and systems. They all work together to make sure that we are functionally healthily. And, they all require the right ‘mix’ of nutrients, from the ‘big guys’ of protein, carbohydrates, and fats, through to the ‘little guys’, the vitamins, minerals, and secondary nutrients like the various antioxidants we get from fruits, vegetables, and berries.

So, first up, we need to ensure that we are getting enough food overall to supply the fuel we need (calories), enough of protein, healthy fats, and appropriate levels of carbohydrate (determined by our genetic makeup), and enough vitamins and minerals to support all the functions of the body.

On this last point is where many of us miss out. Many Kiwis simply don’t get all that they require from food alone. Estimates from the New Zealand Ministry of Health ‘NZ Adult Nutrition Survey’ of 2008/2009 suggest that many New Zealanders are not getting the recommended amounts of many of the vitamins and minerals from their diets.1

Some of the key findings included:

  • Around 20% of people fail to get sufficient vitamins A, B1 and B6.
  • 8% of people fail to get sufficient B12.
  • Around 25% of people don’t consume enough zinc. Interestingly nearly 40% of males do not get adequate zinc from their diet.
  • 45% of people don’t get enough Selenium (a mineral lacking in New Zealand soils).

If you are lacking in any of these nutrients, your immunity is not going to be up to scratch!

Good Green Stuff provides these nutrients (and more) in an easy, once-daily, multi-nutrient drink, based on whole-food extracts.

Specific nutrients in Good Green Stuff for immunity


Zinc is an essential mineral commonly lacking in the diet, particularly of children and as we age. The immune system doesn’t work properly without adequate zinc,2, 3 and zinc supplementation is recommended, especially if you are prone to frequent infections.   

Taking a zinc supplement is likely to reduce the duration and severity of colds and flu-like viruses.4

Vitamin C

Vitamin C, or Ascorbic Acid, can help to reduce symptoms of colds and shorten their duration.5 Some studies also suggest that regular use through the cold season might help to prevent colds.6, 7 Regular and consistent use of Vitamin C gives the best effects (in other words, not just taking it when you start to feel a cold coming on!) Vitamin C appears to be especially useful for athletes for reducing post-exercise cold symptoms.

Panax Ginseng

Ginseng is a herb used extensively in traditional Chinese medicine and other traditional healing systems. Studies show that Ginseng can help to prevent the common cold, and if you do get one, it can help to reduce duration and severity.8-10  Seniors might especially benefit from ginseng for preventing flu-like illnesses.10


Probiotics are healthy bacteria that colonise the gut. They help to fight harmful bacteria and viruses that cause illness, reduce the chance of allergens and irritants entering the body, and directly help the body to modulate its immune responses. Specific Lactobacillus and Bifidobacteria can help to reduce colds, respiratory infections, and ear infections in children. 11, 12Probiotics are another supplement that seems to especially benefit athletes. A Lactobacillus supplement given to elite athletes over a 4-month reduced the number and severity of respiratory.13

Several studies show that probiotics and probiotics combined with either multivitamins or minerals help prevent colds and/or reduce their duration and severity in adults.14-16

Vitamin D

Vitamin D is an essential vitamin produced in the skin as a result of sun exposure. Many people do not get enough sun or eat enough vitamin D containing foods to preserve health and performance. Supplemental Vitamin D3 can help to prevent respiratory infections.17

Other immune-boosting herbs

Other herbs included in Good Green Stuff have a long history of use in traditional medicine systems for promoting improved immunity including ashwagandha, astragalus, and shiitake mushroom.



  1. University of Otago and Ministry of Health. A Focus on Nutrition: Key findings of the 2008/09 New Zealand Adult Nutrition Survey. Wellington: 2011.
  2. Fraker PJ, Gershwin ME, Good RA, Prasad A. Interrelationships between zinc and immune function. Fed Proc. 1986;45(5):1474-9.
  3. Chandra RK, Dayton DH. Trace element regulation of immunity and infection. Nutrition Research. 1982;2(6):721-33.
  4. Science M, Johnstone J, Roth DE, Guyatt G, Loeb M. Zinc for the treatment of the common cold: a systematic review and meta-analysis of randomized controlled trials. CMAJ : Canadian Medical Association Journal. 2012;184(10):E551-E61.
  5. Hemila H, Chalker E. Vitamin C for preventing and treating the common cold. The Cochrane database of systematic reviews. 2013;1:CD000980.
  6. Van Straten M, Josling P. Preventing the common cold with a vitamin C supplement: a double-blind, placebo-controlled survey. Advances in therapy. 2002;19(3):151-9.
  7. Sasazuki S, Sasaki S, Tsubono Y, Okubo S, Hayashi M, Tsugane S. Effect of vitamin C on common cold: randomized controlled trial. Eur J Clin Nutr. 2006;60(1):9-17.
  8. Predy GN, Goel V, Lovlin R, Donner A, Stitt L, Basu TK. Efficacy of an extract of North American ginseng containing poly-furanosyl-pyranosyl-saccharides for preventing upper respiratory tract infections: a randomized controlled trial. Cmaj. 2005;173(9):1043-8.
  9. McElhaney JE, Goel V, Toane B, Hooten J, Shan JJ. Efficacy of COLD-fX in the prevention of respiratory symptoms in community-dwelling adults: a randomized, double-blinded, placebo controlled trial. Journal of alternative and complementary medicine (New York, NY). 2006;12(2):153-7.
  10. McElhaney JE, Gravenstein S, Cole SK, Davidson E, O'Neill D, Petitjean S, et al. A placebo-controlled trial of a proprietary extract of North American ginseng (CVT-E002) to prevent acute respiratory illness in institutionalized older adults. J Am Geriatr Soc. 2004;52(1):13-9.
  11. Hatakka K, Savilahti E, Pönkä A, Meurman JH, Poussa T, Näse L, et al. Effect of long term consumption of probiotic milk on infections in children attending day care centres: double blind, randomised trial. BMJ. 2001;322(7298):1327.
  12. Rautava S, Salminen S, Isolauri E. Specific probiotics in reducing the risk of acute infections in infancy--a randomised, double-blind, placebo-controlled study. Br J Nutr. 2009;101(11):1722-6.
  13. Cox AJ, Pyne DB, Saunders PU, Fricker PA. Oral administration of the probiotic Lactobacillus fermentum VRI-003 and mucosal immunity in endurance athletes. Br J Sports Med. 2010;44(4):222-6.
  14. Winkler P, de Vrese M, Laue C, Schrezenmeir J. Effect of a dietary supplement containing probiotic bacteria plus vitamins and minerals on common cold infections and cellular immune parameters. International journal of clinical pharmacology and therapeutics. 2005;43(7):318-26.
  15. de Vrese M, Winkler P, Rautenberg P, Harder T, Noah C, Laue C, et al. Effect of Lactobacillus gasseri PA 16/8, Bifidobacterium longum SP 07/3, B. bifidum MF 20/5 on common cold episodes: a double blind, randomized, controlled trial. Clinical nutrition (Edinburgh, Scotland). 2005;24(4):481-91.
  16. Tubelius P, Stan V, Zachrisson A. Increasing work-place healthiness with the probiotic Lactobacillus reuteri: A randomised, double-blind placebo-controlled study. Environmental Health. 2005;4:25-.
  17. Laaksi I, Ruohola JP, Mattila V, Auvinen A, Ylikomi T, Pihlajamaki H. Vitamin D supplementation for the prevention of acute respiratory tract infection: a randomized, double-blinded trial among young Finnish men. The Journal of infectious diseases. 2010;202(5):809-14.


Leave a comment