Tuesday, 15 December 2015

19. Chemo, Superbugs and Diet

     The ultimate superbug that is resistant to the ultimate antibiotic has reached Europe in an apparently inexorable global spread from China.
     In November the medical journal Lancet Infectious Diseases reported that researchers in China had discovered bacteria with a dangerous new antibiotic-resistance gene that is spreading from livestock to people in China. This newly identified gene, called MCR-1, is on a mobile piece of DNA known as a plasmid that can copy itself and jump from bacterium to bacterium, spreading antibiotic resistance; the modern superbug.
     Mobile resistance genes spread quickly in the modern world of global traffic; riding in people, animals, and food across continents. MCR-1 bestows resistance to the antibiotic colistin, which, although it has been around for 50 years, is considered the last drug available to treat some deadly infections. It actually fell out of favour due to kidney toxicity and was largely replaced by aminoglycoside antibiotics such a streptomycin, which might explain why it is still effective.
     Colistin is used extensively in animal agriculture in China, where this superbug first appeared and made its jump from animals to humans, and has now been found on a person in Denmark.  
Colistin is also approved for use in factory farming in the European Union and unless action is taking quickly to ban the indiscriminate use of it and other antibiotics in animal agriculture and aquaculture, our livestock production facilities will become breeding grounds for colistin resistant and other multidrug resistant bacteria that will inevitably enter into our food supply and humans.
     Antibiotics such as colistin are essential infection suppressors in chemotherapy treatment, which indiscriminately kills not only cancer cells but also the patient’s immune system. If we cannot contain the spread of bacteria resistant to colistin, and other antibiotics, we could face increasing numbers of untreatable infections afflicting cancer patients at a time when they are at their most vulnerable. Transplant patients taking immuno-suppressant anti-rejection drugs are equally at risk.
     That being said, we need to concentrate on four things to stop cancer:  cancer prevention, research into effective treatment for pre-cancerous states, seek alternative cures to chemotherapy, and make more sensible use of our available antibiotic arsenal
There is some movement in this direction:
Prevention: There is a growing understanding of the importance of lifestyle and diet on prevention of a number of cancers, as advocated in this blog. Carcinogenic pesticides are now understood to cause inflammation leading to cancers such as bowel cancer when introduced into the human food chain via animal feed. There is a growing awareness of the effects of pesticides on our health  and increasing demand for Non-GMO and organic food in our shops and supermarkets.
Treatment: As noted elsewhere under Research, the University of Manchester Viral Oncology Research Laboratories announce encouraging research results into an effective answer to cervical cancer at its treatable pre-cancerous stage.
Cure: Associated US companies AddVie and J & J have just announced excellent trial results for a new drug that significantly reduces death risk and disease progression vs chemotherapy in late stage leukaemia patients.
Further Reading 
Gene Watch  GM crops and foods in Europe and UK.  
GM Freeze  Where to buy non-GM fed animal produce UK.
Non-GMO Shopping Guide USA Listing.
Soil Association  Anti-biotics, farm animals and the need for change.
The Lancet Infectious Diseases :  Colistin resistance: a major breach in our last line of defence.
Breastcancer.orgHow Chemotherapy Affects the Immune System.
Manchester 1824 :  HIV Drug used to reverse effects of virus that causes cervical cancer.
Reuters  Trials Drug cuts death risk vs chemo.

Thursday, 3 December 2015

18. Frankenfish are here! Farmed Salmon and Cancer

The U.S. Food and Drug Administration (FDA) has now approved the first genetically modified food animal for farming; an Atlantic salmon inserted with genes from Chinook salmon and eelpout (an eel-like fish) to make it grow twice as fast as natural wild salmon. The genetically modified salmon's sex hormones have also been manipulated to ensure they're all female and sterile. 

Eelpout fishing: Photo Eelpout fun 

This strange 'Frankenstein with scales' or 'poefish', named after Frankenstein's creator Edgar Alan Poe, has been created for factory-farming in tanks on land. It opens the floodgates to many other edible farmed animal species including chicken, pigs, cows and other fish species now waiting in the genetic engineering pipeline.
Remarkably, the US Food and Drug Administration will not require additional labeling to identify this culinary aberration when it appears in our shops, which it surely will when land-based fishmeat manufacturers and their supermarket outlets latch on to the economics of shorter production cycles and reduced feed costs for 'poefish' production. This fishmeat is produced in "facilities that resemble warehouses, eliminating any interactions between the farmed fish and the external environment", to quote the website of Aquabounty Technologies.  
Believe it or not, as far as the FDA are concerned, this 'poefish' is classed as a drug, not a fish, "because the recombinant DNA construct introduced into the animal meets the definition of a drug." But, because this 'poefish' is allegedly nutritionally equivalent to conventionally farm-raised Atlantic salmon, it doesn't need to be labeled either as a drug or as a genetically engineered product.  So presumably it will just be labeled as 'farm-raised'

 Photo: Kruger Kaldnes RAS and Veolia Water Technologies 

Which brings me at last to my blog:
 Diet, Nutrition, Farmed Salmon and Cancer. 
Wild salmon absorb carotenoid from eating pink krill, giving the salmon's  otherwise grey meat its distinctively appealing pink colour. Farmed salmon get no krill in their cage pens so are fed canthaxanthin, a chemical pigment manufactured by pharmaceutical giant Hoffman-La Roche.
The European Commission scientific committee on animal nutrition issued a warning about the pigment and urged the industry to find an alternative. But the British Food Standards Agency took the position that normal consumption of farmed salmon poses no health risk and has not banned the pigment from animal feed. Cancer can strike some years after the seeds have been sown however, so one wonders whether the FSA took this incubation time factor into account. 
Scientists are far more concerned however with studies that show that farmed salmon accumulate significantly more cancer-causing PCBs and toxic dioxins than wild salmon thanks to their pellet feed cocktail, which contains higher concentrations of fish oil than wild salmon normally consume. Man-made contaminants, PCBs, dioxins  and insecticides make their way into the ocean and are absorbed by marine life. These pollutants accumulate in fat that is distilled into the concentrated fish oil extracted from sardines, anchovies and other ground-up fish to form the pellets fed to the farmed fish.  It takes 4.5 kilo of wild fish to produce 1 kilo of fishmeal pellets fed to a farmed salmon.  
                                                         Photo: Picjumbo

Thanks to their concentrated fishmeal, farmed salmon are far fattier than their wild cousins, but they contain less of the beneficial omega-3 fatty acids. They also ingest a cocktail of chemicals  antibiotics, pesticides, and other carcinogenic chemicals.  Pesticides like teflubenzuron are given to the farmed salmon in their sea cages to combat the sea lice which infest their overcrowded pens, (up to 90,000 fish in an area just 100ft by 100 ft is not unknown. The mess they make leaches out into the sea to create a major industrial seaboard pollutant that seriously impacts both on local wild sea life and migrating salmon; a vicious circle. 
A residue of the toxic cocktail ingested by the caged fish remains in the plastic shrink-wrapped farmed salmon steak which you buy in your supermarket.  It will not be long before it is a genetically engineered faux-pink 'poefish' on your plate, masquerading as farmed, or even wild, salmon. Unless, that is, you buy certified 'wild caught' salmon when it is in season, and has survived the sea louse pollution from fish farms in its migration from and return to its spawning river. 
Further Reading 
AquaCounty Technologies   Modern Genetics and Aquaculture
Los Angeles Times  Fish farms become Feedlots of the Sea.
About.com  What's Wrong with Fish Farms?
Mercola.com   FDA Approves Genetically Engineered Salmon
ABC News  Frankenfish. GMO Salmon declared safe to eat
Wikipedia    Sea lice which parasitize salmon farms and interact with wild fish.

Wednesday, 11 November 2015

17. Cooking Oils and Cancer - a new study

     Experiments at De Monfort University, recently published by the Daily Telegraph have shown that corn and sunflower oil used in frying can release dangerously high levels of toxic chemicals known as valdehydes, which have been linked to cancer, and heart disease and dementia. Experiment leader Dr Martin Grootveld, a professor of bioanalytical chemistry and chemical pathology at the University has stated that  “a typical meal of fish and chips” fried in these vegetable oils contained up to 200 times more aldehydes than are considered safe. Olive oil, butter, and coconut oil, on the other hand, contained far lower levels of aldehydes.
During his appearance on BBC’s Trust Me, I’m a Doctor, Dr. Grootveld gave volunteers sunflower oil, vegetable oil, corn oil, cold-pressed grapeseed oil, olive oil, butter, goose fat, and lard, and asked the participants to cook foods with them every day. Leftover oil from their cooking was collected and sent to the lab at De Montfort University where they found that sunflower oil and corn oil produced aldehydes at the highest levels, and that it was actually safer to use olive oil, butter, lard, or coconut oil.
     "People have been telling us how healthy polyunsaturates are in corn oil and sunflower oil. But when you start… subjecting them to high amounts of energy in the frying pan or the oven, they undergo a complex series of chemical reactions, which results in the accumulation of large amounts of toxic compounds.” Dr Grootveld commented. 
     “Sunflower and corn oil are fine as long as you don’t subject them to heat, such as frying or cooking,” Grootveld said in a press release. “It’s a simple chemical fact that something which is thought to be healthy for us is converted into something that is very unhealthy at standard frying temperatures.” Olive oil, meanwhile, is much better “because lower levels of these toxic compounds are generated, and secondly, the compounds which are formed are less threatening to the human body.
     For years we have been subjected to official health advice not to use butter or lard for cooking. These  experiments however show that both are very good for frying purposes.  I myself will stick to light olive oil for cooking, and a stronger flavoured virgin olive oil for use in salads.  

The following article in Stuff.co.nz expands on the issues and is well worth reading.  

Stuff.co.nz    Vegetable Oil and Cancer                                                                                                

Friday, 14 August 2015

16. Obesity and Cancer

We all know that smoking is one of the leading causes of cancer - you can't buy cigarettes without being reminded of this on the packet. Within the decade however, obesity will overtake smoking as the lead cause of cancer according to specialists at the recent American Society of Clinical Oncology (ASCO) conference in Chicago. They pointed out that spiralling rates of obesity meanws that cancer, once seen as a disease of old age, is now being diagnosed up to twenty years earlier.                              

We now know that excess weight increases your risk of cancer significantly.  The risk of prostate, colon, womb and all other gynaecological cancers, particularly breast cancer, is elevated, due to the hormone imbalances associated with obesity, which fuel tumour growth.             

The intimate relationship between obesity and cancer does not stop there however, according to Dr. Eric Horwitz, radiation oncology lead researcher at the Fox Chase Cancer Center - American Oncologic Hospital, Philadelphia. His studies have found a correlation between obesity and increased risk for both cancer relapse and spread.  Overweight survivors of prostate cancer treatment were found to have a three percent higher rate of relapse compared to their slimmer counterparts. They also had seven percent higher odds of the cancer spreading.

        Further Reading
        Daily Telegraph   Obesity and Cancer
        American Society of Clinical Oncology (ASCO)  Obesity and its   impact on breast cancer.
        Fox Chase Cancer Center  Ongoing cancer clinical trials.
        Rocketswag  Overweight or obese?

Thursday, 23 July 2015

15. Deep Fried Mars Bars and French Fries

Deep Fried Mars Bar by Xian from Lancaster

     Recent nutritional studies by researchers at Tehran and Toronto universities into dietary patterns and breast cancer risk show that healthy eating was associated with eliminating three-quarters of the odds of breast cancer, whereas less healthy eating was associated with up to nearly eight times the odds. Included in the unhealthy eating pattern was the consumption of deep-fried foods, which have previously been linked to breast cancer, pancreatic cancer, lung cancer, oral and throat cancers. Researchers at the Fred Hutchinson Cancer Research Centre in Seattle found that regular intake of deep fried foods, in this instance French fries, chicken, fish, and doughnuts appeared to contribute to the progression of prostate cancer as well.
      The problem lies in the heat of deep fry oil, which can generate potentially carcinogenic compounds, when chicken and fish are cooked at high temperature. Deep-fried plants, on the other hand, can form acrylamide.
     Acrylamide intake has been associated with risk of endometrial cancer, ovarian cancer, lung cancer, kidney cancer, and throat cancer. The level of cancer risk associated with French fries depends on how long and hot they’re fried and to avoid the generation of carcinogenic compounds and acrylamide, cooking temperature and cooking time should be as low and as short as possible.
     Despite promises by the food industry to the European Food Safety Authority of self-regulation and control of fry times there appears to have been little change to date.
     Blanching potatoes before deep frying reduces the formation of acrylamide but potato chip manufacturers and chippies complain that this reduces flavour and leaches away some vitamin C, though if you are relying on potato chips for your daily dose of vitamin C, you probably won't be thinking too seriously about cancer producing compounds.
     As with all dietary advice, moderation is the key word.  An occasional deep fry-up is not going to give you cancer, though a daily dip into deep fries may be shortening the odds – not only on cancer but obesity which is a quick route to a number of cancers – see my blog 14.
     No cancer risk study has yet been published on the consumption of that alleged Scottish delicacy, the Deep fried Mars Bar. I recently saw an online recipe for this, served with French fries….eat that dish too often, and cancer risk will be the least of your worries!

Further Reading

Friday, 17 July 2015

14. Sugar and Cancer.


     The Government's new guidelines on sugar consumption and obesity provide disturbing reading for those with a sweet tooth.  The report published today by the Scientific Advisory Committee on Nutrition, (SACN), recommends that no more than 5% of our daily energy in a healthy diet should come from sugars, including those 'free sugars' naturally present in unadulterated honey, fruit juice and other foods. This is a 50% reduction on the previous nutrition guidelines published back in 1991 and nutritionists warn that people conforming to the new guidelines, (which also recommend a 50% increase in fibrous foods consumed), will need to make extreme changes to their present diet.
     The problem with our sugar consumption has been that few have stuck even to the old guidelines of 10%, causing an obesity and diabetes crisis across the entire age spectrum, and the necessity of a new government strategy to tackle childhood obesity and tooth decay. 
     The chart below shows the recommended daily 5% sugar intake:

Maximum sugars intake per day (source: SACN report)

GramsSugar cubesTeaspoons (4g-6g in a teaspoon)
4 to 6 years 19 3 - 5 
7 to 10 years 24 4 - 6 
11 years and above30 5 - 7
      For a child under 11 years of age, 24g or 4-6 tsp of sugar recommended is the equivalent of just two bowls of a cereal like Frosties or  2/3rds of a can of coke and no other sugary food or drink at all for the day.   The 30g limit for adults is down from the old guidelines of 70g for men and 40g for women and is equivalent to one bar of chocolate a day and no other sugar.
     The Government organisation Public Health England, (PHE), is particularly focused on the childhood statistics which show one in three children aged 10 or 11 to be overweight or obese. They point to sweetened fruit juices, squash and fizzy drinks as being a major contributor to this.  
     PHE don't mention cancer in their deliberations but I will, since this blog is all about diet and cancer.  Excessive sugar intake must be regarded as a direct route to cancer because it leads to the Obesity'Clapham Junction' from which we travel on to at least 10  cancerous destinations.  Clinical studies have shown that obesity can lead to non-Hodgkin’s lymphoma, leukemia, multiple myeloma, and cancers of the kidney, colon, rectum, breast (in postmenopausal women), pancreas, ovary, and prostate. 
     So cut out those fizzy drinks and beware the sugar content when you buy tomato based pasta sauce, coleslaw, flavoured water, low fat yoghurt and French Fries! 

Update 11.11.15. 
I have followed Jamie Oliver's campaign to reduce sugar intake by persuading the government to introduce a sugar tax. I confess I thought the idea had merit, but the results of a sugar tax imposed in Denmark make me wonder.
Check out this <iframe src="https://embed.theguardian.com/embed/video/commentisfree/video/2015/nov/11/sugar-tax-facts-need-to-know-video" width="560" height="315" frameborder="0" allowfullscreen></iframe> youtube before you make up your own mind.

Dr. Ian Hampson, Reader in Viral Oncology, Institute of Cancer Studies, University of Manchester, comments:  
     One of the most obesity-related cancers in post-menopausal women is endometrial (uterine) carcinoma which is increasing rapidly.        
     In the UK the incidence has increased by half from early 1990's and in 2012 there were 8,500 cases in the UK (23 women every day).  This is actually the cancer which has the strongest link to obesity with type II diabetes also being a major contributory factor. 
     The problem is that obesity disturbs and de-regulates the effects of insulin and this in turn leads to a greater risk of cancer. Curiously, if the process is reversed by exercise, diet etc this often cures the type II diabetes and the risk of cancer also declines!

Further Reading
Association of Obesity and Cancer Risk in Canada
Obesity and Cancer Risk: Recent Review and Evidence
Obesity and post-menopausal breast cancer 

Monday, 22 June 2015

13. Diet and Cancer: a clinical research problem.

     It struck me very early on when writing this blog on nutrition and cancer that I had stepped into a virtual minefield; a field sown in the shifting sands of informed opinion that is littered with the bones of once-considered truths that have since been abandoned by dieticians in the light of new and often apparently conflicting evidence. Clinical research on nutrition and cancer prevention is regrettably sparse and is sadly lacking in trial depth in comparison to similar research and trials on drugs for a cancer cure. I wondered why this should be and invited Dr. Ian Hampson of the Institute of Cancer Sciences at the University of Manchester to discuss this anomaly.  This is his illuminating reply: 

     Diet is one of many environmental factors that combine with the genetic hand we have been dealt to promote the development of cancer. The problem with nutrition and diet, however, is that we keep getting it wrong.
     We are now beginning to appreciate that early foetal or newborn dietary programming must be taken into account, (see link to the US National Library of Medicine below).  It seems that the diet to which we are exposed in early life, and even in the womb, fixes the goalposts for what our bodies regard as normal. Our response to nutrients in early life can therefore influence how we will respond to these in later life. This in turn determines our susceptibility to many cancers and, indeed, to a whole range of diseases.  Superimpose this on the worldwide differences in youth and adult lifestyles, diet, exercise and ethnicity and you have created a complex equation, which probably explains why there are so many conflicting studies and calls for further research. It also explains why the success of clinical trials that embrace all parts of this equation would be impossible within a reasonable human timeframe, ethnic spectrum and realistic budget.
      Our newfound appreciation of the impact of early foetal and newborn nutrition and diet on our susceptibility to cancer and other diseases in later life does however open up the possibility of some disease preventive control in the future by the administration of prenatal or postnatal dietary supplements.  But that calls for yet further research!
     Meanwhile, eat a diet which is abundant in fruits, vegetables, whole grains, nuts, legumes and olive oil. Choose fish and poultry, lean sources of protein, rather than red meat, which contains more saturated fat.  This is what is known as the Mediterranean diet.  Also observe moderation in all things! Even exercise – too much is actually bad for you!
Dr Ian Hampson,
Reader in Viral Oncology,
University of Manchester

I was interested to read Dr Hampson's Mediterranean diet recommendation in his final paragraph.  The 'Mediterranean diet'  has  recently been pronounced as beneficial, not only in risk reduction of a growing number of cancers such as uterine cancer, (see my blog  12),  but is also associated with good general health, a healthy heart and weight control or obesity - itself a potential cause of some 22 different cancers according to studies published in The Lancet, including liver, colon, ovarian, breast and prostate cancers, (see my blog 3).

Further reading