Poultry – high in fat with a bit of cancer on the side
Beef is well known for its harmful nutritional effects, and lately has even been found to be a significant factor in premature death. In comparison, poultry is often suggested as a healthy and dietetic alternative to beef. However, along with the moral reasons to avoid poultry, whose production involves even greater cruelty than in beef production, you should know that it isn't especially healthful either.
"Lean" meat – 22% fat
First, let's examine poultry's nutritional composition: Is it really low-fat? This question is critical in the determination of poultry's nutritional value, since animal fat has been found in a series of studies to be a cause of diseases, especially heart disease and elevated cholesterol, as a result of its high saturated fat content. Therefore even conservative bodies such as the USDA (the American ministry of agriculture, which is in charge of national nutritional recommendations) recommends reducing the consumption of animal fat.
Some say that poultry is lean meat, and that the fat content can be reduced by removing the skin. However, in practice a substantial part of the fat does not reside in the skin but rather accumulates in body organs, especially the legs. Due to poultry's inability to move around in the coops, and due to their deficient diet, they fatten up quickly, similarly to the pathology known among people; for poultry that suffer from obesity, the muscles get filled with fat. In recent years, along with the increased industrialization of farming, poultry has become even more fatty. A review of poultry composition published in Cambridge University's 2009 study in the journal Public Health Nutrition shows that the fat content of poultry rose in hundreds of percentage points over the years, from 8% in 1970 to the huge amount of 22%-23% in 2004. The researchers point this out as one of the likely causes for the large increase in obesity in the Western world.
The connection between poultry consumption and obesity received yet another confirmation in a study published in the prestigious American Journal of Clinical Nutrition. In the study, which included 373 thousand participants, a significant connection was found between meat consumption and obesity – and surprisingly, the influence of poultry's consumption on body weight was found to be even stronger than that of consumption of red meat (fresh or processed). The connection remains significant even after neutralizing variables such as physical exercise, age, sex, and even the total daily caloric intake.
Carcinogens on the grill
In research by the European Prospective Investigation into Cancer and Nutrition (EPIC), one of the biggest and most important studies in the field of the connection between health, nutrition and life habits, which examined no less than 411 thousand participants over eight and a half years, they found an increased rate of lymphoma among those who consumed large amounts of poultry. The researchers are undecided on whether to attribute this result to the carcinogenic viruses found in poultry (such as ALV, which we will address later on), to the dioxin toxins that it contains, or to its antibiotic residues*. Poultry contains not only carcinogenic viruses but also an abundance of other carcinogens (mostly of the HCAs type). Most of the carcinogens are created in the muscle tissues (the protein) in the meat at high temperatures or in long cooking – barbeque, grilled chicken, and even skillet-fried chicken breast. The carcinogenesis of these substances is the result of significant changes that they cause in the cellular DNA. A pilot study found an increased amount of these carcinogens in the urine after eating fried chicken breast. The presence of these carcinogens in the urine indicates that they have passed through the blood stream.
In another study, a statistically significant connection was found between cancer of the urinary bladder and the consumption of poultry without the skin. The risk for getting this type of cancer rose to 50% among examinee's who consumed five servings of poultry a week. It should be noted that such a connection has not been found to the consumption of poultry with the skin. Generally, considering the large number of ingredients in the diet, it is difficult to isolate the influence of a single ingredient and to prove a causative connection between itself and cancer. In any event, a number of studies have proved that vegetarians have a lower risk for cancer**, as it seems this is due to the combination of avoiding meat and its products and a high consumption of healthy foods with significant anti-cancerous potential. Fruits, vegetables, and legumes have been found in a long series of studies to reduce the risk for cancer, among other illnesses, due to plant fiber and phytochemicals content, which can neutralize biochemical processes with cancerous potential.
Chicken legs hygiene: food poisonings and urinary tract inflammations
According to the veterinary services report 2010, an animal food source lab found salmonella in 31.2% of the poultry samples. In another part of the report dealing with microbiology and poultry diseases, it was documented that out of the 8,000 samples taken, only 10% were not contaminated with any kind of bacteria and 85% of the samples were contaminated with E-coli (a type of bacteria which is naturally found only in the digestive system).
A study from 2010 found that this germ is constantly found in the poultry's digestive system, breathing system, and on the skin and feathers, and is becoming more common as the hygiene and crowdedness worsen in the coop. This phenomenon occurs because on factory farms the chickens wallow in their own feces, and as a result their whole body gets covered in these germs. In other words, finding E-coli in 85% of the samples indicates that poultry consumption is bound with the consumption of poultry feces. The Center for Disease Control of the American ministry of health estimates that each year some 48 million Americans (one of every six Americans) suffer from food poisoning, out of which 128 thousand are hospitalized and 3,000 die directly from the poisoning itself. The most sensitive population is that with the weakest immune system – pregnant women, children, the elderly, and the sick. Among those hospitalized, 35% were poisoned by salmonella and 28% die as a result of the salmonella poisoning. In Israel, too, salmonella prevalence is high: according to the Ministry of Health in the year 2009, 1,517 cases of salmonellosis were diagnosed. The prevalence of the disease is especially high among infants up to the age of 4.
E-coli bacteria which are frequently found in poultry have also been found to cause urinary tract inflammations in two Canadian studies from 2010 and 2012, which examined outbreaks of urinary tract inflammations which reached epidemic proportions in some locations. Isolation of the inflammation-causing bacteria revealed specific substrains of E-coli of the ExPEC strain. In these patients, the researchers found that the bacteria's genetic sequences were very similar to those found in frozen meat samples and in preprocessed chicken bodies from slaughterhouses at the time of the disease outbreak. In the past it was assumed that the germs reach the urinary bladder from the patients' anus, but these studies may indicate the poultry industry as the origin of the germs in the intestines. A further confirmation of this claim is found in a study from 2005, which found a genetic resemblance between the E-coli strain which causes urinary tract infections and the E-coli which causes the colibacillus disease, which kills chickens in the poultry and the egg industries.
A comprehensive review on the subject from 2010 in the International Journal of Environmental and Public Health widely refers to this subject, emphasizing the high prevalence of antibiotic-resistant E-coli bacteria among poultry. One of the reviewed studies found that 97% of the E-coli isolated from diseased chickens were resistant to antibiotics of any type and 87% were resistant to a number of types of antibiotics. The researchers also quote a long series of studies which found a high prevalence of antibiotic-resistant E-coli germs in poultry samples. One of the reasons for the high prevalence of germs and of the colibacillus disease is the overcrowding and the filth in the coops. Yet the industry would usually prefer the "solution" of feeding the animals with antibiotics over improving the chickens' living conditions.
In order to establish a direct link between the consumption of poultry and urinary tract inflammations, further studies are needed. But these studies undoubtedly point out a distressing connection between common diseases on factory farms and the high prevalence of E-coli pathogens in humans, causing food poisonings and urinary tract inflammations, which in some cases are even resistant to antibiotics.
Arsenic and other toxic metals
Once in a while, articles are published in the media about various toxic substances in animal products, in poultry among others. For instance, last year channel 2 revealed a report by the veterinary services' committee for trace chemicals in food, according to which 17% of all the poultry livers sampled contained cadmium (a toxic metal) in quantities which exceed the permitted levels. A few years earlier, the state comptroller's report revealed that poultry were fed with a growth inducer which contained arsenic (a carcinogen). Nowadays, too, growth inducers containing various toxins are being used. Accurate data about the amounts of toxins in poultry are hard to obtain because of deficient supervision by the veterinary services (they sample only 0.002% of the poultry slaughtered for food), which received criticism in Judge Zeiler's report.
Cancer for every worker
The pathogens found in poultry present a risk not only to consumers but also to the hard-working laborers employed in the poultry industry. Proff. Eric Johnson from the UNT's Health Science Center's Department of Epidemiology has been studying the health of workers in slaughterhouses and meat processing plants in the United States for dozens of years. Among his findings: In a followup on 2,500 workers in slaughterhouses and processing plants in Baltimore, he found an increased risk for mortality from cancer (such as myeloma and cancers of the pharynx, esophagus, lung, and liver), diabetes, thyroid gland problems, neurological complications (such as senility), cardiovascular diseases, abdominal inflammations, kidney and urinary tract diseases, and a series of less familiar diseases. According to the study, the main reason for the increased rate of illness is the various viruses found in poultry, to which the workers are exposed. The main virus mentioned was ALV (Avian Leucosis Retrovirus), which causes lymphoma and other cancer types in poultry, and to which an elevated level of antibodies was found among the workers.
* The researchers state that the findings concerning an increased risk for lymphoma due to poultry consumption are surprising compared to previous studies, and raise a few hypotheses:
- Toxins and carcinogens such as dioxins are found among others in poultry and in milk, but since the study did not find a connection between lymphoma and milk consumption, it appears that this theory should be renounced.
- There is an intensive use of antibiotics on factory farms, both for treating diseases and as a growth catalyst. Direct consumption of antibiotics at high frequency among people has been found to be related to an elevated risk for lymphoma (NHL). However, for the moment it is unclear whether the consumption of poultry which was treated with antibiotics causes the same effect.
- A number of studies have found a decreased risk for NHL type lymphoma with prolonged cooking, and the researchers mention that the presence of carcinogenic viruses in meat, especially if incompletely cooked, reinforces this finding. This hypothesis therefore sounds convincing; however, as mentioned above, prolonged cooking may also result in the creation of other carcinogens, and is therefore inadvisable.
** The most prominent research in the field was published in the British Journal of Cancer in 2009 and examined the incidence of cancer among 61,566 participants over 12 years. The research showed that the risk for various types of cancer is 12% lower for vegetarians than meat-eaters.
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