How could phytochemicals defend our cells against abnormalities?
This page highlights the published laboratory data highlighting potential mechanism for certain foods for background information only and does not imply Pomi-T® has specifically demonstrated these effects:
The most commonly cited effect of phytochemicals is via their anti-oxidant properties, protecting the DNA from oxidative damage resulting from ingested or environmental toxins [Porrini, Parada, McLarty, Sonn]. They work by either moping up free radicals directly or supplying nutrients or the main anti-oxidant enzymes; superoxide dismutase, glutathione or catalase. A league table used to be produced by the FDA which measures foods ability to absorb damaging oxygen species – this is called the Oxygen Radical Absorbance Capacity ORAC but this has now been removed because it has now been recognised that the antioxidant properties is only one part of the story.
Green and black tea, rich in epigallocatechin gallate (EGCG), has been shown to block ornithine decarboxylase, an enzyme that signals cells to bypass apoptosis [Mclarty, Porrini, Liao]. Green tea inhibits the proliferation of unhealthy cells, block de-differentiation and angiogenesis [Yang].
Curcumin gives turmeric its yellow colour, slows down the growth of unhealthy cells by blocking the cell cycle, increasing apoptosis, preventing the invasion and migration of cells [Somasundaram, Shah, Zhang, Iqbal]. It has cox-I mediated anti-inflammatory properties [Handler], and inhibits the growth of stem cells that give rise to damaged cells [Kakarala].
Pomegranate, rich in ellagic acid, inhibits the proliferation of damaged cells and induces apoptosis in laboratory studies [Retitig, Lansky, Malik, Khan, Barber, Choi]. As a natural anti-oxidant, it has a protective effect against cell damage.
Broccoli, rich in isothiocyanate and sulforaphane, inhibit growth and promote apoptosis of unhealthy cells [Sarkar]. In humans, regular intake down-regulates genes associated with unhealthy cell growth and up-regulates genes linked to the suppression of unhealthy cells [Gasper, Moysich, Joseph, Heinen].
What is evidence that polyphenol rich diets are beneficial to health?
Diets rich in polyphenols, the natural plant-based phytochemicals found in healthy foods, have been linked with lower risks of chronic illnesses [Denny, Elments, Karppi, Rezai-Zadeh, Porrini]. A healthy lifestyle including a polyphenol rich diet has been linked to a slower rate of PSA progression amoung men [Ornish].
Boosting the diet with a daily nutritional supplement
Food supplements can be split into two main categories. Those which extract chemicals from foods and concentrate them into a pill and those which concentrate selected whole foods:
Supplements containing extracted chemicals.
By far the largest categories of these supplements contain minerals and vitamins although some can contain extracted polyphenols such as lycopene, saw palmetto and genistein.
However, long-term vitamin and mineral supplementation should be discouraged unless they are used for correcting a known deficiency, and future studies should include detailed micro-nutrient testing.
Whole food supplements
Interventional studies of polyphenol-rich food supplements are gaining momentum as, instead of extracting chemical micro-nutrients, they concentrate whole foods as a convenient way to boost the daily intake of polyphenols. They are however, scarce, often under-powered, non-randomised, and have multiple overlapping interventions making the results difficult to interpret [Posadzki]. Despite these drawbacks, there are some interesting data emerging. In a small study of American men, a tea extract was linked with a beneficial effect on PSA [McLarty]. In a phase II study, PSA doubling time was significantly prolonged and markers of oxidative stress improved upon regular consumption of pomegranate juice [Pantuck]. In two further phase II studies, one from USA and the other from Italy, men had pomegranate seed extract, and similar effects on PSA were observed [Carducci, Paller].
Although polyphenol-rich supplements are showing some promise, not all polyphenols help defend our cells against abnormalities, and those that do, have different benefits in different combinations amongst different individuals [Parada, Greenhall, Moysich, Porrini]. The largest and scientifically robust evaluation was the pomi-t study. This double blind RCT involved 200 men showing a 63% difference in the rate of rise of PSA [Thomas ASCO 2013].
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Choi C, Liao Y; Wu S; Leu Y; Shen Y. The structure of pomegranate has no hormonal component (2006). Mass Spec Food Chem, 96; 4, 562.
Denny A, Buttriss J. Plant foods and health: focus on plant bioactives. 2007. EU Information Resource (EuroFIR) Consortium. Contract FOOD-CT- 2005-513944
Elmets CA, Singh D, Tubesing K, et al. Cutaneous photoprotection from ultraviolet injury by green tea polyphenols. Journal of the American Academy of Dermatology 2001; 44(3):425–432.
Gasper AV et al (2005) Glutathione S-transferase M1 polymorphism and metabolism of sulforaphane from standard and high-glucosinolate broccoli. Am J Clin Nutr 82: 1283–1291.
Handler N, Jaeger W, Puschacher H, Leissser K, Erker T. Synthesis of noval curcumin analogues and their evaluation as selective cyclooxygenase-1 inhibitors. Chem Pharm Bull. 2007 55(1): 64-71
Iqbal M, Sharma SD, Okazaki Y, Okada S (2003) Dietary supplementation of curcurmin enhances antioxidant phase II metabolosing enzymes in mice. Pharmacol Toxicol; 92 (1); pp33-8.
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Shah BH, et al (1999). Inhibitory effect of curcumin, on platelet-activating factor through inhibition of thromboxane formation and Ca2+ signaling. Biochem Pharmacol., 58(7): 1167–1172.
Tsang C, et al. Intake of pomegranate influences urinary glucocorticoids, BP and homeostasis model assessment of insulin resistance in human volunteers. (2102) J Nut Sci, 1, pp 1-9