Tuesday, May 24, 2011

Does fat shrink your brain?

Being an epidemiologist sure seems to! Working class people are more likely to be fat and they are dumber anyway. That alone could account for the epidemiological findings.

The gastric bypass study is more interesting but we are not told why some had surgery and some did not. Almost certainly those who had surgery were more distressed and that may have included a greater incidence of sleep apnoea and other things -- such as depression -- that DO impede alertness

Just last month, researchers at the Karolinska Institute in Sweden declared the risk of dementia in later life is 71 per cent higher for overweight people, and around four times greater for those who were obese in middle age.

The problem, say scientists, is fat, as it causes the brain to shrink.

‘We know that a fatty diet clogs our arteries and is bad for our heart, and it does exactly the same thing to blood vessels in the brain,’ explains Paul Thompson, professor of neurology at the University of Los Angeles and an expert in this field.

His team found the brains of overweight and obese subjects were, on average, between 4 and 8 per cent smaller than the brains of those who were at a healthy weight. ‘This is because blood can’t get through so easily to the brain — it’s starved of oxygen and the brain cells eventually die, he says.’ This has the effect of prematurely ageing the brain.

The researchers, who examined brain scans of nearly 100 people aged over 70, concluded the brains of overweight people were on average eight years older than those of their healthy counterparts. ‘We based this on the fact that the average person loses 0.5 per cent of their brain a year,’ says Professor Thompson. ‘The overweight people had already lost 4 per cent more than someone of a normal weight, so they were effectively eight years older.’

The news was worse for obese people: ‘They had lost 8 per cent of their brain, so they were 16 years older. It won’t kill you, but there will come a point when it’s noticeable — when about 10 per cent of your brain tissues have died,’ he adds.

And for the obese, there is more bad news: the scans also revealed the areas where the shrinkage was most pronounced were those responsible for reasoning and judgment and the processing of long-term memories.

Whether you’re obese or just overweight, the researchers believe a shrunken brain is less resilient to damage from the abnormal protein clumps in the brain called plaques that kill brain cells and cause Alzheimer’s. ‘It may be that you are building up plaques in the brain and then being obese tips you over the limit into having Alzheimer’s,’ says Professor Thompson.

To support this, other research has shown obese individuals have less grey matter and more white matter than people with healthy BMIs.

‘Obese people, or those who have a binge-eating disorder, may also have differences in the structure of some parts of the brain compared with their thinner counterparts,’ says Dr Goldstone. ‘Some studies have shown subtle differences in how dense and well organised the grey or white matter in the brain of obese people and those who are not.’

But could losing weight or having obesity surgery improve memory and cognitive functioning once again? The evidence emerging suggests it may well do, according to researchers at Kent State University, Ohio.

The memories of 150 overweight people were tested before some of the participants underwent gastric bypass surgery. Around 12 weeks after surgery, those who’d had the operation showed improvements in memory, moving from a score of mildly impaired into the normal range. The improvements were not mirrored in the patients who didn’t have surgery.

Tests included the ability to recall words, problem solving and reaction times.

So what is causing the improvement in these people’s brains? ‘Research has shown that when people gain weight they tend to have more problems learning and recalling new information, problem solving and co-ordination,’ says John Gunstad, associate professor in the department of psychology, who led the research. ‘It’s a really big challenge to work out why, but it’s thought the changes in blood pressure and glucose levels that accompany weight gain might also be to blame.

‘In addition, obese people are more likely to suffer from sleep apnoea, which affects concentration during waking hours. ‘There are a whole host of possible factors. What we do know is that losing weight seems to enable the brain to function normally again.’


The Facts of Lunch: Federal School Regulations Aren’t The Answer

There is nothing wrong with fighting childhood obesity but fighting it at the federal level with ineffective methods that could cost each school district over $100,000 in budget increases isn’t going to cut it.

Every school district is different and it would be more appropriate to make these decisions at the state and local level so that the best options for each individual district can be provided for those particular students.

Regulators at the U.S. Department of Agriculture mistakenly assume their preliminary new federal rules to make school lunch healthier will naturally result in healthier kids. For many schools, the less tasty meals will be wasted, leaving oversized garbage cans full of costly fruits, veggies and hyper healthy portions the schools paid a pretty penny for.

And by schools, I mean the state taxpayers who have no say in what kind of regulations populate their local school districts. The total cost for the new rules is estimated to reach $6.8 billion, according to the Department of Agriculture.

Not only will the schools be adding more fruits and veggies, they will be adding more expensive products to ensure freshness – an unnecessary extravagance for most districts within this already expensive upgrade.

And the latest proposal? Removing white potatoes – meaning school lunches would absent tater tots and French fries – beloved staples of the school lunch tray for generations. Schools in Texas are even dishing out $2 million to install cameras that will monitor the calorie intake of students. The lunch trays will include bar codes for researching purposes. What a waste of taxpayer dollars.

The House subcommittee on Early Childhood Elementary and Secondary Education held a hearing Friday on the USDA’s preliminary regulations, which are an extension of President Obama’s Healthy, Hunger-Free Kids Act, signed last year.

The truth is that limiting the amount of nutrient-empty food available to students is a no-cost way to help fight childhood obesity. In a testimony on federal food programs, Heritage’s Robert Rector said:

Changing the composition of foods offered by schools may have positive results on children’s weight and would not impose added costs on the taxpayer.

A great many schools are already adopting this sort of policy. What is needed here is flexibility and experimentation. There is, no need for mandatory national standards, nor for the U.S Congress to assume the role of national “cookie czar,” dictating food policies for local schools. Such a usurpation of power would be unwise and unwarranted.

Instead of the federal government attempting mandate standards for every faceless school district in the country, they should look to state and local education leaders for direction on what policies work in different areas. A school district in southern Texas is not going to need the same things as one in inner city New York. Why doesn’t the federal government make that connection?

America is fighting record debt right now – cutting costs at every available corner. Implementing this kind of unnecessary federal regulation while we are attempting to reconcile our economy is an irresponsible move at the wrong time.


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