Sunday, June 30, 2013

Children who eat lots of chicken are less likely to develop bowel cancer later in life

And red meat did no harm!

At the end of the article below, the authors express some appropriate humility about the generalizability of their chicken findings.  In a major departure from epidemiological convention, they allow that correlation might not be causation!

Teenagers who regularly eat chicken are less likely to develop bowel cancer when they get older, new research shows.  Scientists found poultry reduced adolescents’ risk of a bowel tumour by around 20 per cent and cancer of the rectum by up to 50 per cent.

The research, by experts at Harvard University School of Public Health in Boston, U.S., shows chicken appears to reduce the development of adenomas, harmful growths which are a precursor to cancer.

The study is the first to show that bowel cancer risk later in life can be influenced by the type of meat eaten as a teenager.

Diets high in fat and red meat, as well as lack of exercise, are thought to be among the main risk factors.

Researchers wanted to see if meat consumption relatively early in life had any impact on cancer risk decades later.  This is because the development of bowel cancer is a slow process that can take several decades.

They tracked nearly 20,000 women who took part in a long-running research project called the Nurses’ Health Study 2, which began back in the late nineties.

At the start of the study, all the women had given details of dietary habits during childhood and adolescence.  They were then monitored to see how many over the following decade were diagnosed with adenomas.

The results, published online in the American Journal of Epidemiology, showed that women who ate the most chicken during their teenage years were the least likely to have the pre-cancerous growths.

However, the researchers also found those that ate the most red meat were no more likely to get cancer than those who consumed the least, while eating fish did not appear to have a protective effect.

Although the study was confined to women, it’s likely that the findings apply to both sexes.

Researchers admitted there is no obvious explanation for why poultry appears to have a protective effect and said the findings could be skewed by the fact they relied on women remembering what they had eaten years earlier.

In a report on their findings they said: ‘There is no well-established plausible mechanism to explain it.

But it is possible that poultry intake during adolescence is simply a marker of a healthy diet or lifestyle that may track through the course of life.’


Tofu rots your brain

Reasonable data below too  -- thus giving the conclusions some weight

Brain Aging and Midlife Tofu Consumption

By Lon R. White et al.


Objective: To examine associations of midlife tofu consumption with brain function and structural changes in late life.

Methods: The design utilized surviving participants of a longitudinal study established in 1965 for research on heart disease, stroke, and cancer. Information on consumption of selected foods was available from standardized interviews conducted 1965–1967 and 1971–1974. A 4-level composite intake index defined “low-low” consumption as fewer than two servings of tofu per week in 1965 and no tofu in the prior week in 1971. Men who reported two or more servings per week at both interviews were defined as “high-high” consumers. Intermediate or less consistent “low” and “high” consumption levels were also defined. Cognitive functioning was tested at the 1991–1993 examination, when participants were aged 71 to 93 years (n=3734). Brain atrophy was assessed using neuroimage (n=574) and autopsy (n=290) information. Cognitive function data were also analyzed for wives of a sample of study participants (n=502) who had been living with the participants at the time of their dietary interviews.

Results: Poor cognitive test performance, enlargement of ventricles and low brain weight were each significantly and independently associated with higher midlife tofu consumption. A similar association of midlife tofu intake with poor late life cognitive test scores was also observed among wives of cohort members, using the husband’s answers to food frequency questions as proxy for the wife’s consumption. Statistically significant associations were consistently demonstrated in linear and logistic multivariate regression models. Odds ratios comparing endpoints among “high-high” with “low-low” consumers were mostly in the range of 1.6 to 2.0.

Conclusions: In this population, higher midlife tofu consumption was independently associated with indicators of cognitive impairment and brain atrophy in late life.


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