Wednesday, March 23, 2011

Sufferers blame stress for breast cancer, despite no scientific link

The article below is quite sensible about stress so it is a pity that the authors are so positive about other dubious causes of cancer. Contrary to their assertions, for instance, some big studies show that fat women get LESS breast cancer

STRESS is often blamed for breast cancer despite no scientific proof of a link. And while many point to stress they also commonly overlook other lifestyle-related issues - such as smoking and obesity - where there is a clear link to the cancer. These are the key findings of research which took in the views of almost 1500 Australian breast cancer survivors.

It found just over four in 10 (43.5 per cent) believed there was a factor which contributed to their cancer and, among these women, more than half (58.1 per cent) blamed stress. The women also pointed to previous use of hormone therapy (17 per cent), a family history of cancer (9.8 per cent). Two per cent attributed their cancer to other lifestyle factors.

"It is concerning that only two per cent of the women in the study attributed their breast cancer to lifestyle factors such as diet, exercise and alcohol consumption," said Christine Bennett, chair of the Bupa Health Foundation Steering Committee which part-funded the study. "There is scientific evidence that being overweight, smoking and excessive alcohol are risk factors."

Women aged under 40 were more likely to believe there was a reason for their breast cancer.

Dr Bennett said that while the exact causes of breast cancer were unknown, studies into the effect of stress on the body and looking for potential triggers of breast cancer did not reveal a link. And despite commonly-held views to the contrary, there was "no scientific evidence that points to stress as a cause of breast cancer".

The Bupa Health Foundation and Well-Being after Breast Cancer Study and was led by Robin Bell, Deputy Director of the Women's Health Research Program at Monash University and Alfred Hospital. Professor Bell said it showed women often responded to a breast cancer diagnosis with a new resolve to improve their overall health, usually through improved exercise.

This was beneficial, she said, although women should be wary of making changes which could be counter-productive in the fight against cancer - such as removing all dairy products from the diet. "Cutting out dairy products may remove some fat from the diet but it could have a negative effect on the bone health of women who, due to some cancer treatments, are already at risk of osteoporosis," Prof Bell said.

Of those who blamed stress, Prof Bell said, the women could also feel a sense of mistaken guilt that they should have acted sooner. "If doctors are aware of this guilt, they will be in a better position to help women address their feelings and overcome their distress," Prof Bell said.

The research is published in the March edition of the journal Psycho-Oncology.


Aging brains not so decayed

Perhaps it’s out of a sense of panic but sometime in middle age we begin to develop the ability for bilateralisation — when faced with a perplexing problem, to use both sides of our brain instead of one.

One of the first scientists to spot this was Dr Cheryl Grady, a neuroscientist at the University of Toronto. In the early Nineties she observed the ageing brain with positron emission tomography (PET) scans. These measure changes in blood flow as brain regions activate, and Grady wanted to find out if an older brain acted in the same way as a younger one in routine tasks such as matching faces.

She assumed they’d be much worse and muster fewer brain cells. But to her surprise, the older adults performed just as well as the younger ones, and they consistently used more of their brains, not less. Older adults used their brains in a new way. They tapped into the same brain circuits as the younger adults, but they also recruited an additional region — their powerful frontal cortex, the front of the brain which is responsible for problem solving.

We have two frontal cortex, one on each side of the brain (known as hemispheres). Just a few years after Dr Grady’s discovery, another study found that while young people switched between sides, older adults used them both at once.

An intriguing aspect of this two-brain phenomenon is that it’s not the weakest brains that do this but the most capable who resort to this trick. It’s as if the best and the brightest older brains, accustomed to being held in the highest esteem, simply refuse to give in. As Grady herself concludes: ‘The higher the education, the more likely the older adult is to recruit frontal regions, resulting in better memory performance.’


Despite long-held beliefs that we become less clever as we age, there’s mounting evidence to suggest the contrary — that we become cleverer.

How can that be? How can we possibly be cleverer and be putting the bananas in the laundry basket and unable to remember why we’ve come to the hardware store?

One of the longest, largest and most respected life-span studies, the Seattle Longitudinal Study, was started in 1956 and has systematically tracked the mental powers of 6,000 people for more than 40 years.

Led by Sherry Willis, a psychologist, the study has found that people function better on cognitive tests in middle age, on average, than they do at any other time tested.

The abilities that Willis and her colleagues measured include vocabulary — how many words you can recognise and find synonyms for; verbal memory — how many words you can remember; number ability — how quickly you can do multiplication, division, subtraction, and addition; spatial orientation; perceptual speed — how fast you can push a button when you see a green arrow; and inductive reasoning — how well you solve logical problems.

What the researchers found is astounding. During the span of time that constitutes the modern middle age — roughly 40 through to the 60s — the people in the study did better on tests of the most important and complex cognitive skills than they had when they were in their 20s.

In vocabulary, verbal memory, spatial orientation, and, perhaps most heartening of all, inductive reasoning — people performed best, on average, between 40 and 65.

Top performance was reached a bit earlier for men, who peaked in their late 50s, while women’s scores kept climbing into their 60s.


It’s said that the true test of a human brain is its ability to figure out other human brains. And research shows that judgment does improve with age. Thomas Hess, a psychologist at North Carolina State University, has done studies of what he calls ‘social expertise’, which he finds peaks in midlife, when we are far better than those younger and older at judging the true character of others.

By middle age, we not only have more years of experience, but the brain cells devoted to navigating the human landscape turn out to be exceptionally durable.

Scanning studies show that parts of the brain that deal more with regulating emotion shrink less quickly than other areas as we age. And it’s that mix of emotional control, mental prowess, and life experience that helps us make the right calls.

David Laibson, from Harvard University, has done fascinating studies in the emerging field of ‘neuroeconomics’ — how people use their brains to make financial decisions — and he, too, finds we’re most adept at this in middle age.

When confronting complex money issues, such as mortgages or interest rates, those in middle age make the best choices; in fact, our economic judgment is best in our 50s.

It may be what holds the areas of the brain together that’s also important. This is known as the white matter, which is made up of myelin — the fatty outer coating of the trillions of nerve fibres. Myelin acts like insulation on a wire and makes the connections work.

This layer of fat, some experts believe, is what makes the brain work so well in middle age. Scan studies of the brains of men aged 19 to 76 have found that in two crucial areas of the brain, the frontal lobes and the temporal lobes — the region devoted to language — myelin continued to increase well into middle age, peaking, on average, at around 50, and in some, continuing to build into the 60s.


Many of us grew up dreading old age and its chronic disappointments. But what actually happens is that our moods get not worse but better.

I must say, this idea seemed more than odd to me at first. In the thick of middle age myself, cheeriness is not the first word that comes to my mind. But as we get older we actually react less to negative things — we know this thanks to scans of the amygdala, a small, primitive part of the brain that decides how we are going to react to a situation.

The amygdala’s default setting is pretty much to respond negatively. But now brain scans have suggested that our amygdalae respond less and less to negative stimuli as we age. Our brains, in some automatic way, begin to accentuate the positive and eliminate the negative.


No comments: