1. Red Meat and Cancer

     People have been banging on for some time now about the cancer risks of eating too much red meat or processed meat.  
     A recent Harvard University study published this year has shown that high quantities of red meat appear to raise the risk of breast cancer in women by 22%, while an earlier study showed that the risk of bowel cancer was raised by 33%. 

     The problem has been that nobody knew why large amounts of red meat had this effect on humans but not on other mammal carnivores. 

     New research on 'red meat derived glycans' at the San Diego Glycobiology Research and Training Center of the University of California, presented for publication in Proceedings of the National Academy of Sciences, appears to provide the reason for this health anomaly.  

     Red meats are evidently particularly rich in a sugar which is naturally produced by other mammal carnivores but not by humans. When humans eat large amounts of beef, pork or lamb therefore, their bodies trigger an immune response to the foreign sugar, producing antibodies which promote inflammation and possible progression not only to Cancer but also to Type 2 Diabetes, or cardiovascular disease which in turn lead to stroke and heart attack. 

     Red meat is accepted as a good source of protein, vitamin and minerals, but an increasing body of research suggests it is bad for long-term health if taken in large amounts.  So what do health experts consider "a large amount"?  Dieticians now recommend eating no more than 2.5oz (70g) a day. This is the equivalent of three slices of ham, one lamb chop or two slices of roast beef a day. And if you are a carnivore, at least one meatless day in the week would certainly be good for you.

                                                                                                                             

Further Reading.

Proceedings of the National Academy of Sciences USA.  Study on the  connection between red meat, inflammation and cancer progression. 
Nature Communications . Fat, Fibre and Cancer Risk.