Plant-Based Diets: A Powerful Weapon Against Cancer

Most, if not all, of you will have heard about how a plant-based diet helps in the battle against cancer, but how important is it? An NBC News article published in November 2017, stated that a new American Cancer Society (ACS) report had revealed that 42% of cancers (45% of cancer-related deaths) were preventable, with tobacco topping the list of causes, accounting for 19% of cases (28.8% of deaths). Obesity comes in second at 7.8% (6.5% of fatalities), alcohol at 5.6% (4% of deaths), UV radiation at 4.7% (1.5% of fatalities), physical inactivity at 2.9% (2.2% of deaths), poor diet at 1.9% (2.7% of fatalities) and Human Papillomaviruses infection at 1.8% (1.1% deaths). Since the National Cancer Institute states that inherited mutations (i.e. genetics and thus a non-preventable cause) play a role in only 5%-10% of cancers, it does leave a huge black hole of around 45% of cancers with no identifiable cause, even if you include the impact of difficult-to-measure causes like stress, toxins and air pollution.

Could this mean that the percentages attributed to some of these causes, particularly poor diet, are inaccurate? I think the answer has to be ‘yes’.  I found it interesting that the report also concluded that “the combination of excess body weight, alcohol intake, poor diet, and physical inactivity accounted for the highest proportion of all cancer cases in women and was second only to tobacco smoking in men.” Since obesity is largely due to excessive consumption of highly-processed foods with no or limited nutritional value, the percentage of ‘poor diet’ as a cause of cancer increases. The by-product of this is, of course, that obese people will simply not be able to exercise. The ACS report goes on to say “These four combined risk factors also accounted for the second highest proportion of cancer deaths in both men and women.”

A diet rich in fruits and vegetables, particularly those which are organically grown, is likely to not only increase your chances of preventing cancer or healing it should you be diagnosed, but will enable you to feel an awful lot healthier too. This was shown in a ground-breaking study in 2014 which analysed the findings of 343 peer-reviewed publications on the differences in composition between organic and conventional crops. The study, led by Carlo Leifert, Professor of Ecological Agriculture at Newcastle University, and published in the British Journal of Nutrition found the following:

  • Pesticide residues four times less likely in organic crops than in conventionally grown ones. 
  • Concentrations of the toxic heavy metal, cadmium, 48% lower in organically grown crops (cadmium is one of only three metal contaminants that the European Commission has set maximum contamination levels for in food, with mercury and lead being the other two). 
  • Up to 69% higher levels of some key antioxidants, like polyphenolics, which numerous studies have linked to a reduced risk of certain types of cancer.

As Professor Leifert concludes, “The organic vs non-organic debate has rumbled on for decades now but the evidence from this study is overwhelming – that organic food is high in antioxidants and lower in toxic metals and pesticides”. 

Fruits and vegetables grown through intensive farming methods are treated with a vast number of synthetic chemicals which can be hazardous to human health. According to The Soil Association, the UK’s leading food and farming charity and organic certification body ‘almost 300 pesticides can be routinely used in non-organic farming and these are often present in non-organic food people eat despite washing and cooking’. These include herbicides (e.g. Chlorpropham which can cause damage to organs with prolonged exposure, insecticides (e.g. Cypermethrin used to kill caterpillars and which comes with the warning ‘may be fatal if swallowed and enters airways’), fungicides (e.g. Fenhexamid coming with the warning ‘wash concentrate/dust from skin or eyes immediately’), plant growth regulators (e.g. Benzyladenine which is harmful to aquatic life) and weed killers (e.g. Glyphosate identified as ‘probably carcinogenic’ by the World Health Organisation). Organic farmers, on the other hand, are only permitted to use 20 pesticides and those which they do use are derived from natural ingredients like citronella, clove oil and pyrethrin found in the chrysanthemum flower.

At a 2017 Royal Society of Medicine conference, Professor Leifert,  presented startling data on the huge increase in the number of such chemicals being used since the 1970s when, for instance a potato was treated with 5.3 active ingredients compared with 30 today; a x 5.8 increase. A leek or onion bought in 2014 had been exposed to an average of 32.6 active ingredients compared with just 1.8 in 1974; a x 18 rise. Wheat – ground into flour and used in multiple products from bread to thickening ready-meal sauces – was treated with just 1.7 active ingredients in 1974, rising to 20.7 in 2014; a x 12 increase. The real danger to human health lies in the toxic residue which remains in fruit and vegetables on the supermarket shelves despite these pesticides being declared safe according to Maximum Residue Levels (MRLs). The problems are two-fold. Firstly, these MRLs are applied to pesticides individually, not collectively, and so the impact of a “cocktail effect” cannot be measured, and secondly, the effect of eating a succession of different pesticides is also not considered. Therefore, the risks to human health rise considerably when one factors in the huge number of different pesticides with which our fruit and veg are treated these days.      

Organic fruits and vegetables are sometimes difficult to get hold of and do tend to be more expensive than conventionally-grown crops, but if you can buy them, you should try and do so. The evidence for improved health in organically-grown crops is there: higher concentrations of cancer-fighting antioxidants, less cadmium and less pesticide residues.

So, go onEat The Rainbow!

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