Friday, July 16, 2010



Millions swear by fish oil pills but now some experts say they're a waste of money - so who's right?

They are so popular and the object of so much research that we would expect a few positive effects by chance alone. And a few positive effects are all that have been shown.

Some of the claims below are extravagant: "It's also not disputed that fish oil is essential for unborn babies' brains". My wife took no fish oil and ate no fish that I can remember while she was pregnant with our son and he is now doing his Ph.D. in mathematics. Where did we go wrong?

I also note that London Metropolitan University figures prominently below. They seem to be something of a haven for food faddism


Are omega-3 fatty acids vital for our health or simply today's version of snake oil? Over the past few years we've read of the fantastic benefits of omega-3s, found in fish oils.

Last week scientists reported that women who take fish oil supplements reduce their risk of breast cancer by a third. But while experts agree omega-3 pills can cut the risk of heart disease and are vital for brain development in the womb, opinion is divided over other benefits.

Tom Sanders, professor of nutrition and dietetics at Kings College London, and Professor Amanda Kirby, specialist in developmental disorders at the University of Wales, have dismissed many - but not all - of the benefits of omega-3 pills.

However, neuroscientists and nutritionists recently told a London conference that many Britons' health is at risk as they aren't getting enough omega-3 from fish.

'There's an epidemic of brain and mental disorders in the UK, such as ADHD, depression and cerebral palsy, which cost the Government £77 billion a year,' says Professor Michael Crawford of the Institute of Brain Chemistry at London Metropolitan University. 'The evidence shows the lack of omega-3 from fish in our diet is a major factor.'

This clash of scientific opinion makes things confusing - do we need fish oil pills or not? Here we look at the evidence to help you make the right choice...

WHY DO SOME EXPERTS DISMISS FISH OIL PILLS?

The reputation of omega-3s as a panacea has made them a popular supplement. Found naturally in oily fish, such as mackerel and sardines, they are added to many foods from eggs to orange juice, while capsules are found on chemists' shelves.

Official bodies, such as the Food Standards Agency (FSA), say you can get enough from eating oily fish. But not everyone likes oily fish, so millions have taken omega-3 in a pill form.

Such pills are the best-selling supplements in Britain. Professor Sanders says we're wasting our money. The results of recent trials testing the benefits of fish oil pills on the brain found them no better than a placebo.

A trial of 450 school pupils by Professor Kirby found no difference in reading, spelling or handwriting between those who got fish oil for a year and those on a placebo. Another trial failed to show that fish oil supplements helped keep elderly patients' minds sharp.

Other studies have proved equally disappointing. The results of a review of research into the benefits of omega-3 on children with ADHD were too inconsistent to draw any conclusions.

A review of the effects on depression and mental health problems found no benefit. Professor Crawford disputes this. Since the Seventies, he believed the rise in heart disease was down to lack of omegas. 'I predicted that a lack of good fats was going to eventually show up as damage to the brain. That is what is happening.'

But haven't studies shown that supplements don't boost mental performance? 'If you want to have a big impact on the brain, the crucial time is just before and after birth,' says Crawford. He dismisses the trial that found no effect on primary school pupils.

'The way the benefit was measured was very wishywashy,' he says. 'It relied on the mothers' opinion.' More reliable, he says, is evidence presented at the recent conference, which showed a measurable effect of fish oil on children's brains.

Robert McNamara, associate professor of psychiatry at the University of Cincinnati College of Medicine, gave healthy eight to ten-year-old boys a dose of either 0.4 grams or 1.2 grams of omega-3 fatty acids or a placebo every day for eight weeks.

When he then scanned their brains while they were doing a task requiring them to focus, he found the areas needed for attention were more active in those who'd had the fish oil, but not the placebo.

Omega-3 supplements might also benefit adults at a high risk of developing a psychotic disorder, a study published in the Archives Of General Psychiatry found. Only five per cent of the patients who took a daily 1.2 gram omega-3 supplement later became seriously mentally ill, while more than a quarter of those in the placebo group progressed to severe psychosis.

SO WHAT ARE FISH OILS GOOD FOR?

Even sceptics agree that some of the claims for fish oil have good evidence to back them up. The strongest of these is that omega-3s cut the risk of heart disease if you have had a heart attack. It's also not disputed that fish oil is essential for unborn babies' brains.

Evidence that it reduces pain and inflammation if you have arthritis is also strong. The jury is out on other claims. Omega-3s have been tried as a treatment for asthma, with limited success.

Results are better for macular degeneration, which damages the centre of the eye and can lead to blindness. One study of more than 3,500 patients in 2006 found those eating the most fish cut their risk of developing the disease in half.

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Having a big head may help you fight dementia

Hmmmm ... A number of complications here: 1). High IQ people have bigger heads; 2) People with autism have bigger heads. Those two may be connected if autism is caused by an overdeveloped cerebral cortex, which is one of the more plausible theories. I think the results below simply show that the more you have to start with, the longer it takes you to lose it

Being called big-headed is somewhat of an insult, but a new study suggests people with larger heads may be better protected from the ravages of dementia.

Scientists found that large-headed individuals with Alzheimer's have better memory and thinking skills than sufferers with smaller heads.

The difference can be seen even when the amount of brain cell death is the same in both groups.

Study leader Robert Perneczky, from the Technical University of Munich in Germany, said: 'These results add weight to the theory of brain reserve, or the individual capacity to withstand changes in the brain.

'Our findings also underline the importance of optimal brain development early in life, since the brain reaches 93 per cent of its final size at age six.'

Head size is one way to measure brain reserve and growth, he said.

While brain growth is partly determined by genetics, it is also influenced by diet, infections and inflammation.

'Improving prenatal and early-life conditions could significantly increase brain reserve, which could have an impact on the risk of developing Alzheimer's or the severity of symptoms of the disease,' said Dr Perneczky.

The researchers looked at 270 people with Alzheimer's who underwent tests of memory and thinking skills. They were also given magnetic resonance imaging (MRI) scans to assess their levels of brain cell death.

Measurements were taken of the circumference of patients' heads to determine head size.

The results, published in the journal Neurology, showed that having a big head was associated with better test performance despite brain cells dying off because of Alzheimer's.

Specifically for every one per cent of brain cell death, an additional centimetre of head size was linked to a six per cent improvement in memory.

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