Some brief comments which reinforce the recent WHO conclusion on red meat as a carcinogen specifically pork and bacon by using world cancer statistics and a newly developed regression technique  by             Dr Chris Barnes, Bangor Scientific and Educational Consultants    email manager@bsec-wales.co.uk  First published without reference list November 2015. 

Abstract

World cancer statistics and a result from the author’s  prevoius work on cancer and internet penetration and cancer and alcohol are used to support the recent WHO conclusion that rad meat, especially pork and bacon may be carcinogenic.      However, the  result here casts doubt on the assumption that all red meat, especially Lamb is carcinogenic.  It should be stressed that the differences are more than likely due to preservatives employed and not any genetic  feature of the animals   concerned.  A hypothesis is  developed and to some extent supported that preserved pork is a major cause of CRC worldwide.  Red meat, especially lamb may not be so dangerous as suggested by the WHO.   High solar U/V levels and vegetarian diets  would appear to be protective against CRC.  The proscriptions of early religions such as Judaism  and Islam that pork is ‘unclean’ or at least unsafe if preserved appear to be have been vindicated.  

 

Introduction

The WHO has recently branded all red meats but especially preserved meats such as pork and bacon as carcinogenic with respect to especially colon cancer.   Of course this notion is by no means new.   The conclusion is usually arrived at by either the results of animal studies i.e. the feeding of such   meats  or their contained preservatives to animal models or by small to medium scale   excess risk meta-analysis studies on groups of meat eaters and vegetarians    after diagnosis.  Anecdotally, CRC is the second most prevalent major killer in the developed world.  

 

Mechanisms

A suggested mechanism is that  heme iron has a catalytic effect on (i) the endogenous formation of carcinogenic N-nitroso compounds and (ii) the formation of cytotoxic and genotoxic aldehydes by lipo-peroxidation. The former will be highly exaggerated in red meats preserved with nitrate or nitrite such as cured hams, pork  and bacon.   See Basdtide et al (2011).[1]

 

 

World studies

Following a striking discovery that internet penetration correlates extremely well with total cancer incidence world-wide,(Barnes 2015)[2] the present author has recently pioneered new methods using multiple  sequential regression to make comparisons of cancer aetiology in the same realm.   The technique was validated, inter-alia, by independently deducing that Saudi Arabia was shown to have 53%  Internet Penetration yet to have significantly lower cancer rates than predicted by that penetration.  At the time, zero alcohol consumption and good vitamin D status particularly in males  was suggested to account for this. The evidence was strongly backed up by considering the comparative size of the Saudi outlier for the three cancers Breast, Prostate and Bowel.  The rank in order of lowest expected cancer probability ( largest negative outlier)  with respect to the     model was Prostate, Bowel, Breast.   This also confirmed the importance of vitamin D status in these three cancers.   The notion is as follows.  Saudi males get far more exposure to sunlight than Saudi females. As a result their Prostate cancer is far lower than expected.  The bowel outlier is central because both males and females suffer from bowel cancer but only males will have the Vitamin D advantage.  The breast outlier is so small as to be lost in the general scatter and indeed  for breast cancer negative outliers  from several other countries are comparable to or even outlying the one for Saudi Arabia, reflective of the general poor vitamin D  status of the great majority of Saudi women who will not receive much sunlight directly to skin because of traditional/ religious dress code rules.      

 

In a second paper, ‘Using an Internet Penetration Algorithm and multiple sequential linear regressions to establish excess cancer incidence and cancer radiation and other aetiologies, by Dr Chris Barnes, Bangor Scientific and Educational Consultants, Bangor, Gwynedd.  E-mail doctor.barnes@univ.bangor.ac.uk’ the effect of alcohol was looked at more closely, see Barnes 2015 (a) [3].

http://drchrisbarnes.co.uk/pen3_files/image010.png

The R^2 for the above regression  suggests that globally some 29% of cancer incidence could be alcohol related.  Up to 21% of cancer deaths worldwide could potentially be related to alcohol.   At the time of writing I stated that these figures are quite comparable, hence tending to support/justify the new technique  I had developed. What is extremely clear is that there is significantly less chance of cancer in general associated with zero alcohol consumption. The ‘zero’ point above being the data for Saudi Arabia.

 

Some Support for the WHO, the  Saudi  Outlier and Pork!    

What is apparent from the above is that the point on the graph due to Saudi Arabia is a significant negative outlier, this can by deduced even by visual inspection alone.   The author’s technique over-estimates the amount of cancer due to alcohol worldwide by some 8%.    What was overlooked, is that due to religious convention the country which consumes no alcohol also consumes no pork.  Thus is it feasible that pork consumption alone accounts for the difference. Colorectal cancer ( CRC ) is known to account for between 9-10% of cancer worldwide.  The present hypothesis is that this neatly accounts for the above difference and since although Saudi Arabia consumes some red meat this is mainly in the form of lamb. Thus  I would further suggest that the risk of eating red meat alone, without nitrate preservative i.e. something like Lamb or Beef  is significantly smaller    than that for nitrate /nitrite preserved red meat, (the latter being musically the case  for pork, bacon ,sausages etc.) possibly 10 fold so.   

The result for pork, which in its various forms is usually persevered,  is in support of the WHO findings.  However, the WHO concluded that the risk of red meat in general is only slightly less than that for processed meat.  The result derived here would tend not to support that latter conclusion.

 

 

 http://www.indox.org.uk/sites/indox.org.uk/files/GLOBOCAN_MAP2_Fig1Colorectal.pnghttps://anthonycollinsfilm.files.wordpress.com/2012/07/map.gif

 

A more closer inspection of CRC rates across the world is instructive.  CRC rates actually seem to be as low in some countries which   only have up to 30% Muslim population as those with 100%.  I propose that these countries,  such as India and some of those of central Africa enjoy a higher solar u/v index and thus prospective cohorts studied will have better vitamin D  status due to sunlight and not needing to rigorously adhere to any  whole body covering  dress code. A high vitamin   D  status is known to be  highly protective against several cancers, CRC included and presumably balances out the status quo as it were.  

 

Conclusions and further work  

A hypothesis has been developed and to some extent supported that preserved pork is a major cause of CRC worldwide.  Red meat, especially lamb may not be so dangerous as suggested by the WHO.   High solar U/V levels and vegetarian diets  would appear to be protective against CRC.  The proscriptions of early religions such as Judaism  and Islam that pork is ‘unclean’ or at least unsafe if preserved appear to be have been vindicated.  

1.     http://www.ncbi.nlm.nih.gov/pubmed/21209396

2.     http://drchrisbarnes.co.uk/Internet1.htm]#

3.     http://drchrisbarnes.co.uk/pen3.htm

4.