Neue Studie: Rotes Fleisch und Darmkrebs

[zyko]

Titel: Meat consumption and risk of colorectal cancer.

Forscher: Chao A, Thun MJ, Connell CJ, McCullough ML, Jacobs EJ, Flanders WD, Rodriguez C, Sinha R, Calle EE.

Institution: Epidemiology and Surveillance Research, American Cancer Society, Atlanta, Ga 30329-4251, USA.

Quelle: The Journal of the American Medical Association (JAMA). 2005 Jan 12;293(2):172-82.


Zusammenfassung: CONTEX Consumption of red and processed meat has been associated with colorectal cancer in many but not all epidemiological studies; few studies have examined risk in relation to long-term meat intake or the association of meat with rectal cancer. OBJECTIVE: To examine the relationship between recent and long-term meat consumption and the risk of incident colon and rectal cancer. DESIGN, SETTING, AND PARTICIPANTS: A cohort of 148 610 adults aged 50 to 74 years (median, 63 years), residing in 21 states with population-based cancer registries, who provided information on meat consumption in 1982 and again in 1992/1993 when enrolled in the Cancer Prevention Study II (CPS II) Nutrition Cohort. Follow-up from time of enrollment in 1992/1993 through August 31, 2001, identified 1667 incident colorectal cancers. Participants contributed person-years at risk until death or a diagnosis of colon or rectal cancer. MAIN OUTCOME MEASURE: Incidence rate ratio (RR) of colon and rectal cancer. RESULTS: High intake of red and processed meat reported in 1992/1993 was associated with higher risk of colon cancer after adjusting for age and energy intake but not after further adjustment for body mass index, cigarette smoking, and other covariates. When long-term consumption was considered, persons in the highest tertile of consumption in both 1982 and 1992/1993 had higher risk of distal colon cancer associated with processed meat (RR, 1.50; 95% confidence interval [CI], 1.04-2.17), and ratio of red meat to poultry and fish (RR, 1.53; 95% CI, 1.08-2.18) relative to those persons in the lowest tertile at both time points. Long-term consumption of poultry and fish was inversely associated with risk of both proximal and distal colon cancer. High consumption of red meat reported in 1992/1993 was associated with higher risk of rectal cancer (RR, 1.71; 95% CI, 1.15-2.52; P = .007 for trend), as was high consumption reported in both 1982 and 1992/1993 (RR, 1.43; 95% CI, 1.00-2.05). CONCLUSIONS: Our results demonstrate the potential value of examining long-term meat consumption in assessing cancer risk and strengthen the evidence that prolonged high consumption of red and processed meat may increase the risk of cancer in the distal portion of the large intestine.


Diskussion: Bis dato existiert eine ganze Palette an Studien, die einen Zusammenhang zwischen dem Konsum von rotem Fleisch und dem Auftreten von Kolorektalkrebs (Darmkrebs) statistisch nachweisen. Diese neue Studie der American Cancer Society (ACS) ist eine der größten und umfassendsten Arbeiten auf diesem Gebiet. Die Forscher sammelten Daten von insgesamt 148.610 Probanden und verglichen ihre Nahrungsgewohnheiten von 1982 und 1992 mit der Inzidenz von Darmkrebs bis zum 31.08.2001.

Zum Stichtag wurden insgesamt 1667 Fälle von Kolorektalkrebs unter den Probanden diagnostiziert. Dabei wiesen die Forscher einen deutlichen Zusammenhang zwischen dem Konsum von rotem und bearbeitetem Fleisch und der Häufigkeit der Erkrankung nach. Diejenigen Probanden, die am meisten bearbeitetes Fleisch aßen, hatten im Vergleich zu denjenigen, die am wenigsten bearbeitetes Fleisch aßen, ein doppelt so hohes Risiko an Darmkrebs zu erkranken. Die Probanden, die am meisten rotes Fleisch aßen, hatten ein um 40% höheres Darmkrebsrisiko. Unter bearbeitetem Fleisch sind hier Produkte wie Schinken, Salami, Speck und Wurstwaren zu verstehen. Im Gegensatz dazu hatten die Probanden, die am meisten Fisch und Geflügel aßen, ein 20-30% niedrigeres Risiko.

Die Substanzen, die letztendlich für das häufigere Auftreten der Krankheit verantwortlich sind, konnten bisher nicht genau identifiziert werden. Die Forscher dieser Studie stellten die Mutmaßung auf, dass es sich bei den Verursachern des Darmkrebses um Eisen, um Giftstoffe, die beim braten entstehen und um die zum Konservieren benutzten Nitrite und Nitrate handeln könnte.

Folgendes gibt mir daran besonders zu denken: Die High-Risk-Probanden aßen durchschnittlich "nur" 85g rotes Fleisch pro Tag. ein hartgesottener Ketofreak nimmt womöglich im Durchschnitt ein Vielfaches dieser Menge pro Tag zu sich. Zusätzlich kommt der hohe Fettgehalt der ketogenen Ernährung zum tragen, der an sich einen weiteren unabhängigen Risikofaktor bei der Entstehung von Darmkrebs darstellt.

Quelle: http://www.zyko.de/su2101_.html

Die leckersten Sachen sind immer die ungesündesten

beachtet bitte den letzten absatz, den ich da verzapft habe. die high-risk-typen aßen NUR 85g rotes oder bearbeitetes fleisch. man muss kein ketarier sein, um diese menge zu sich zu nehmen. ein gestandener bodybuilder mit einer vorliebe für rindfleisch hat garantiert einen höheren tagesdurchschnitt. oder ein bayrischer bodybuilder, der in seiner mittagspause jeden tag 2 dicke leberkässemmeln isst...

[chillsolutions]

naja, esse eh fast nur schwein und geflügel, aber irgendwas ist da bestimmt auch ungesund

Ich glaube, zu viel darüber nachdenken verursacht Gehirnkrebs
Danke trotzdem, immer wieder interessant sowas

[zyko]

naja, esse eh fast nur schwein und geflügel, aber irgendwas ist da bestimmt auch ungesund

schwein ist rotes fleisch.

[Battle Royal]

Naja es gibt ca 0,0003% neue Darmkrebserkrankungen pro Jahr ... also was solls? die Chance ist gering und ich kann auch morgen vom Auto überfahren werden

[chillsolutions]

naja, esse eh fast nur schwein und geflügel, aber irgendwas ist da bestimmt auch ungesund

schwein ist rotes fleisch.

NEEEEEEEEEEEEEEEEEEEEEEEEEEEEEIIIIIIIIIIIIIIIIIIII IIIIIIIIINNNNNNN



ach verdammt

[bernhard_12345]

ich esse kein rotes fleisch, also bekomm ich keinen darmkrebs!
denn ich bin FARBENBLIND!
@chillsolutions:
wird schon alles wieder gut, sterben müss ma doch alle mal
gruß

[bernhard_12345]

achja und zyko:
HAB GEGLAUBT DAS BÄREN NUR FISCH UND SEEROBBEN FRESSEN und keine kühe und schweine!
gruß

[moroheuz]

Also eines kann ich euch sagen.... so ein schwachsinn von was man alles krebs bekommen kann.

Ich empfehle die da die NEUE GERMANISCHE MEDIZIN.

wenn einer angst vor krebs hat da rein...

dann ist alles etwas entspannter.

denkt einfach an die dioxinverseuchte eier ..... vielleicht gibt es gerad e nicht mehr genug für alle.... (die freilaufenden hennen sind ja auch begrenzt )

also bringt man sowas um den konsum wieder zu verlagern..

also immer locker bleiben

[Elric]

Ich bin echt verwundert, dass ich immer noch lebe.

Esse viel Eiweiß - angeblich ungesund
Trinke viel Wasser - angeblich auch nicht so toll
Trinke regelmäßig milch -wird auch oft abgeraten
Esse auch rotes Fleisch
etc.

Irgendwie müsste ich schon ein Wrack sein, wenn man den ganzen Berichten glauben soll.
Es ist schon erstaunlich, dass die menschliche Rasse noch lebt - bei den vielen Risikofaktoren müsste man schon tot sein, bevor man überhaupt ins fortpflanzungsfähige Alter kommt.

[Milchknilch]

http://www.westonaprice.org/mythstruths/mtbeef.html

Does beef cause cancer?
What about the accusation that beef causes cancer, in particular cancer of the colon? The genesis of this myth involves more than just muddied thinking, but actual skulduggery. In 1965 an influential physician, Ernst Wynder, took the data for the mostly processed vegetable oils, called them animal fat (which they were not) and compared them with worldwide colon cancer mortality.6 The table he produced showed high rates of colon cancer in European countries and low rates of colon cancer in Japan, and concluded that there was a positive effect, in other words, that saturated fat, the kind found in beef, caused colon cancer. What the data actually showed was that consumption of polyunsaturated vegetable oils, not saturated animal fats, was associated with the incidence of colon cancer. And Wynder forgot to mention that Asians have much higher rates than Americans of other types of cancers, particularly cancers of the liver, pancreas, stomach, esophagus and lungs.
Then in 1973, William Haenszel and his colleagues from the National Cancer Institute reported the findings from a study that relied on dietary recall and lacked matched controls—in other words, a very poorly designed study.7 The researchers stated that they found a relationship between beef and colon cancer that fit the earlier work of Wynder. Actually, what they really found was that those westernized Japanese Americans who said they consumed lots of macaroni, green beans and peas, as well as beef, had the highest rates of colon cancer; while traditional Japanese Americans who said they consumed lots of dried cuttlefish, Chinese peas, bamboo shoots, rice and fermented soy products had the highest rates of colon cancer. This second-rate and inconclusive study is firmly fixed in the consciousness of the scientific community as providing evidence for the assertion that beef causes colon cancer.
Two American studies conducted in the 1990's have found a higher risk of colon cancer among those who eat red meat.8 However, no study done in Europe has ever shown an association between meat consumption and cancer.9 This suggests that European sausage and luncheon meat, included in the rubric of "meat consumption," are prepared by traditional methods that require few additives, while the similar products in the United States contain many carcinogenic preservatives and flavorings. Unfortunately, the American Cancer Society's 1996 recommendation that Americans cut down on their consumption of meat—particularly fatty meat—in order to avoid cancer makes no distinction between fresh meats and those that have been embalmed with modern chemicals.
While two US studies have implicated meat consumption as a cause of colon cancer, there are several that contradict these findings. In 1975, Rowland Philips compared Seventh-Day Adventists physicians, who do not eat meat, with non-Seventh Day Adventist physicians, and found that the vegetarian doctors had higher rates of gastrointestinal and colon-rectal cancer deaths.10 National Cancer Institute data show that Argentina, with very high levels of beef consumption, has significantly lower rates of colon cancer than other western countries where beef consumption is considerably lower.11 A 1997 study published in the International Journal of Cancer found that increased risk of colon and rectal cancer was positively associated with consumption of bread, cereal dishes, potatoes, cakes, desserts and refined sugars, but not with eggs or meat.12 And a 1978 study published in the Journal of the National Cancer Institute found no greater risk of colon cancer, regardless of the amounts of beef or other meats ingested.13 The study also found that those who ate plenty of cruciferous vegetables, such as cabbage, Brussels sprouts and broccoli, had lower rates of colon cancer. So just because it's all right to eat beef doesn't mean you shouldn't eat your broccoli.
Actually, we know one of the mechanisms whereby colon cancer is initiated, and it does not involve meat per se. Colon cancer occurs when high levels of dietary vegetable oils and hydrogenated fats, along with certain carcinogens, are acted on by certain enzymes in the cells lining the colon, leading to tumor formation.14 This explains the fact that in industrialized countries, where there are many carcinogens in the diet and where consumption of vegetable oils and carcinogens is high, some studies have correlated meat-eating with colon cancer; but in traditional societies, where vegetable oils are absent and the food is free of additives, meat-eating is not associated with cancer.
Riding piggy back on the alleged association of beef with colon cancer are supposed links with other cancers, such as breast cancer. Here the evidence shows a similarly inconsistent pattern. Cancer is a disease of rich countries where numerous factors can be fingered—altered fats, fabricated foods, low levels of protective nutrients, high levels of carcinogens—and rich countries consume lots of beef. But association is not the same as cause. Countries where there are more telephones have more cancer, but that does not mean that telephones cause cancer. Fat consumption in general also gets the blame for high rates of breast cancer. But a recent survey showed that women on lowfat diets have just as much breast cancer as those on high fat diets.15
High protein diets are said to cause osteoporosis and Americans are now being advised to avoid beef in order to protect their bones. Once again, it's important to look at the studies carefully. Research that showed a link with bone loss and protein consumption was done with purified protein powders.16 With meat, a natural protein food, there was no negative calcium balance. New evidence indicates that women who eat lots of meat had fewer hip fractures compared to those who avoided it.17
High protein diets are said to contribute to kidney problems but, again, the evidence is contradictory. Although protein restriction can be helpful for those who are suffering kidney failure, there is no evidence that eating meat causes kidney disease.18 The fat-soluble vitamins found exclusively in animal fats are very important for healthy kidney function.

http://www.westonaprice.org/traditio...rean_beef.html

For while Korean cuisine is heavily influenced by China, it differs in one important respect – a reliance on beef as the main meat.

...

According to National Cancer Institute data, Korean women have one of the lowest cancer rates in the world (64.9), slightly lower than that of Japan (78.1) and China (88.6), and considerably lower than that of the United States (109.7). For Korean men, the cancer rate falls in the lower middle range (150.3), almost equal to that of Japan and China and slightly lower than that of the United States (150.3) Rates for colon and rectal cancer for beef-eating Koreans are very low, as are rates for lung cancer, breast cancer and cancers of the reproductive organs. But Koreans have the highest rate of stomach cancer in the world. Irritants added to foods – such as talc in white rice – may account in part for high rates of stomach cancer, as well as the prevalence of smoking and consumption of alcoholic beverages, especially among Korean males. Koreans have a relatively high rate of liver disease, also possibly due to consumption of alcoholic beverages without the protective benefits of adequate saturated fat in the diet. The rate of ischemic heart disease is relatively low, about 21 per 100,000, compared to 66.8 in the United States. Average life span in Korea is 70 for men and 77.7 for women.