The chemicals that plants naturally produce to protect themselves against diseases can also help to protect us from getting ill and may even assist our recovery from some diseases. It is not surprising then, that many of the therapeutic properties of herbal medicines are due to the presence of these plant chemicals (phytochemicals). For example tannins (one of these phytochemicals, also found in some teas), which are found in many plants including oak trees, have antifungal properties. They are astringent (drying and tightening) and this property of tannins deters fungi and moulds.
Plant Power
Plants produce more of these chemicals when they are under attack from insects or micro-organisms (fungi, bacteria and viruses), or when they are exposed to other stressors such as UV radiation. Researchers have found that the levels of these beneficial phytochemicals are considerably higher in organically grown fruits and vegetables than in equivalent plants that have been exposed to synthetic chemical pesticides. To exacerbate this effect, some chemicals in pesticides can actually inhibit the production of these phytochemicals rendering food produced with the use of pesticides of much less value in reducing our risk against a large number of diseases.
Golden Oldies
Older varieties of fruits and vegetables have been found to produce higher levels of these protective phytochemicals and because of this they are more resistant to disease than their modern cousins. This makes them a popular choice with organic growers. These chemicals give older plant varieties and wild herbs their stronger flavours including a bitter taste. Many medicinal herbs are also more bitter. Today, bitter is not a preferred flavour, in fact most people dislike it because we just are not used to it any more. But these bitter foods can provide many, many health benefits. The large seed/plant providers have seen to it that the food-plant varieties are rather bland or sweet in flavour to appeal to the modern palate. Manufacturing processes also remove the parts of plants that are bitter and with it most of the health giving properties. Interestingly, it is the bitter tasting plants such as bitter melon, that are often prescribed by herbalists to combat the diabetes resulting from too much sweetness in the diet.
Our Superfoods
So with these in mind, many of our organically grown fruit and vegetables could be considered superfoods because these chemicals provide us with:
- Antioxidants (protecting cells and DNA from damage by toxins, radiation, free/oxygen radicals),
- Anti-inflammatories,
- Antimicrobials and
- Neuroprotectives (which can help protect our brains from ageing).
Plants with the highest levels of these chemicals are usually strongly coloured - red, purple, green, yellow and orange – which is why it’s always important to have a variety of colours on your plate!
Written by Dianna Tawharu (Naturopath). Dianna is the head Naturopath at our Wakefield St store. For more information, get in touch at [email protected]
References:
- https://www.niwa.co.nz/sites/niwa.co.nz/files/uz_nz_and_grapes.pdf
- Zoratti, L; Karppinen, K; Escobar, AL; Haggman, H; Jaakola, L;. (2014). Light-controlled flavonoid biosynthesis in fruits. Front.Plant.Sci
- Cook, M,D; Myers, S,D; Blacker, S,D; Willem, M,E;. (2015). New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists. European J Applied Physiology. 115(11): 2357-2365.
- http://www.orthokennis.nl/artikelen/bitter-is-better-an-introduction-to-salvestrols
- Daniel O, Meier, MS, Schlatter J, et al. (1999). Selected phenolic compounds in cultivated plants: Ecologic functions, health implications, and modulation by pesticide. Environmental Health Perspectives. 107:1
- Kruger.E; Josuttis, M;. (2014). Effects of Growing And Climate Conditions on Berry Yield and Nutritional Quality. https://www.actahort.org/members/showpdf?booknrarnr=1017_43
- Barbara Shukitt-Hale, B; Galli, R,L; Meterko, V; Carey, A; Bielinski, D,F; McGhie, T; Joseph, J,A;. (2005). Dietary supplementation with fruit polyphenolics ameliorates age-related deficits in behavior and neuronal markers of inflammation and oxidative stress. AGE. 27(1): 49-57.
- Potter, G.A; Burke, M.D;. (2006). Salvestrols–Natural Products with Tumour Selective Activity. J Orthomolecular Medicine 21:1
- https://doi.org/10.3389/fpls.2014.00534