Saturday, December 15, 2007

On The "Benefit" of Fruits And Veggies In Cancer

Although a low-fat, high-fiber diet rich in fruit and vegetables has been associated in some studies with decreased cancer risk, findings published in the Journal of the American Medical Association suggest that adding more produce to one's diet may not offer a corresponding benefit. In the study conducted at University of California, San Diego, by John P. Pierce, PhD, and colleagues, among survivors of early stage breast cancer, adoption of a diet that was very high in vegetables, fruit, and fiber and low in fat did not reduce additional breast cancer events or mortality during a 7.3-year follow-up period:
[...] ... women in the early stages of breast cancer who ate substantially more than five servings a day of fruit and vegetables did not have an advantage over their counterparts who followed the five-a-day plan when it came to progression of the disease: The aim of the study, which was carried out at the University of California, San Diego, was to determine whether a diet very high in veggies, fruit and fiber and low in fat would lower three types of risk among women who had been treated for early stage breast cancer:

* risk of recurrence

* risk of new primary breast cancer

* risk of death from all causes

John P. Pierce, PhD, of UCSD and colleagues conducted the randomized controlled trial with 3,088 women between 18 and 70 years old who were previously treated for early stage breast cancer.

About half the women participated in a program that included phone counseling, cooking classes and newsletters that advocated daily targets of five vegetable servings plus 16 oz. of vegetable juice; three servings of fruit; 30 grams of fiber; and 15 percent to 20 percent of energy intake from fat. The other half received printed information describing the "five a day" diet.

During the four-year span of the study, the group that received the extra intervention ate 65 percent more vegetables, 25 percent more fruit, 30 percent more fiber and 13 percent less fat than the comparison group. Both groups of women received similar clinical care.

Breast cancer events occurred in 518 study participants during the study period -- 256 in the intervention group and 262 in the comparison group. Deaths numbered 315, with 155 occurring in the intervention group and 160 in the comparison group.

The results suggested no significant advantage in preventing the recurrence of breast cancer based on demographics, earlier dietary patterns, type of tumor or type of treatment. Researchers followed the women in the study group for 7.3 years and found no evidence that the low-fat diet extra high in fruit, vegetables and fiber was any more helpful in preventing cancer recurrence or death than the five-a-day diet.



The study immediately above is one of many showing that type of diet does not affect cancer. See also here, for instance. But what about total calorie intake? Do fatties get more cancer? We might think so from the article below. There is a lot of weasel wording in the article but one is still left with the impression that fat ladies get more breast cancer. That is an absolute lie. It has been known for some time that they get LESS breast cancer

Diet and breast cancer risk reduction

By Linos E & Willett WC.

The association between diet and breast cancer risk has been investigated extensively and has led to some recommendations for prevention. Research suggests that maintaining a healthy weight may reduce the risk for breast cancer after menopause. Additionally, alcohol increases the risk for breast cancer even at moderate levels of intake, and women who drink alcohol also should take sufficient folate, which can mitigate this excess risk. Interesting questions for future research include the role of soy products, red meat, energy balance, and vitamin D, with particular attention to timing of exposure in early life. Breast cancer is a heterogeneous disease, and dietary factors may differentially affect certain breast cancer subtypes; future studies should therefore attempt to characterize associations according to tumor characteristics.

J Natl Compr Canc Netw. 2007 Sep;5(8):711-718


Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correla-tion coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic condi-tions and lynchings in Raper's data. Raper had the misfortune of stopping his anal-ysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic conditions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.


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