Thursday, December 01, 2011

Fish could protect against Alzheimer's (?)

As it has not yet been through peer review or published, it is very hard to follow this report below about some very elderly people. The article below makes much of the fish not being fried but the research itself does not appear to have examined that. The study appears to be of regular fish eaters without reference to how the fish was cooked. So does the study itself contradict the assertions in the article below? It would seem so.

And note that the fish-eating was ascertained by self report. Knowing that fish-eating is often recommended, it might have mostly been the savvy oldsters who said they ate a lot of fish, whether they did or not. So being more switched on to start with may have been what retarded the development of Alzheimers.

Just the usual epidemiological crap

Eating fish could protect against Alzheimer's disease and memory loss – but only if it is baked or grilled, researchers have claimed.

A study by US scientists found that elderly people who eat fish at least once a week are three to five times less likely to develop the conditions than people who did not.

But it is essential that the fish is cooked in a manner that preserves the vital Omega-3 fatty acids which help protect the brain, researchers said.

Grilling or baking the meat provides the maximum levels of Omega-3, which increase blood flow to the brain, reduce inflammation and limit the build-up of harmful plaques which precedes Alzheimer's.

In contrast fried fish has very low amounts of Omega-3 and consequently offers no protection whatsoever against dementia and age-related memory loss, known as Mild Cognitive Impairment (MCI).

Researchers from the University of Pittsburgh studied a group of 260 healthy volunteers with an average age of 76.

In a study to be presented at the Radiological Society of North America annual meeting tomorrow (WED), they questioned the participants about how regularly they ate fish.

Brain scans carried out ten years later showed that those who did not eat fish regularly had suffered much more shrinkage in key areas of the brain linked to working memory.

A further five years on, they found that 31 per cent of non-regular fish eaters had gone on to develop Alzheimer's or MCI, compared with between three and eight per cent of those who ate fish at least once a week.

Dr Cyrus A. Raji, who led the study, said further studies could help identify whether Omega-3 supplements yielded similar effects, and whether some types of fish offered better protection than others.

He said: "We know from other studies that salmon gives the maximum amount of Omega-3 fatty acids so it is very possible, but we did not look at which fish people were eating in the study.

"Studies like this definitely justify trials that will look at Omega-3 fatty acid supplements. Having said that, I would speculate that taking supplements is no substitute for a lifetime of eating fish."

Dr Simon Ridley, head of research at Alzheimer’s Research UK, said: "This study suggests that eating fish on a weekly basis may reduce the risk of cognitive decline, but it is not clear whether other underlying factors may have contributed to the lower risk in people who eat fish.

"As a number of controlled studies using fatty acids from oily fish have failed to show benefits for dementia, there is a clear need for more conclusive research into the effects of dietary fish on our cognitive health."

Dr Anne Corbett, research manager of the Alzheimer's Society, added: "This moderately sized study adds weight to existing evidence suggesting that eating fish reduces your risk of developing cognitive decline.

"However, this research did not account for lifestyle factors such as other foods or exercise which could also have had an effect. The best way to lessen your chance of developing dementia is to eat a healthy diet including fruit and vegetables along with taking regular exercise and giving up smoking."


Radiation from WiFi connections can reduce sperm activity in up to a quarter of men, study finds

This was research done under totally unnatural conditions so is more of a stunt than a serious study. Any effect was probably due to heat, not the wireless signal. Laptops do get hot to a degree

Working on a laptop wirelessly may hamper a man’s chances of fatherhood. In a study, sperm placed under a laptop connected to the internet through wi-fi suffered more damage than that kept at the same temperature but away from the wireless signal.

The finding is important because previous worries about laptops causing infertility have focused on the heat generated by the machines.

In the latest study, researchers took sperm from 29 men aged 26 to 45 and placed them either under a wi-fi connected laptop or away from the computer. The laptop then uploaded and downloaded information from the internet for four hours. At the end of the experiment, 25 per cent of the sperm under the laptop had stopped moving and 9 per cent showed DNA damage.

By comparison, just 14 per cent of samples kept away from the wi-fi stopped moving. And just 3 per cent suffered DNA damage, the journal Fertility and Sterility reports.

The wireless connection creates electromagnetic radiation that damages semen, the scientists, from the United States and Argentina, believe.

Lead researcher Conrado Avendano, of Nascentis Medicina Reproductiva in Cordoba, said: ‘Our data suggest that the use of a laptop computer wirelessly connected to the internet and positioned near the male reproductive organs may decrease human sperm quality.

‘At present we do not know whether this effect is induced by all laptop computers connected by WiFi to the internet or what use conditions heighten this effect.’

A separate test with a laptop that was on, but not wirelessly connected, found negligible EM radiation from the machine alone.

The findings fuel concerns raised by a few other research teams. Some have found that radiation from mobile phones creates feeble sperm in the lab, for example.

And last year urologists described how a man sitting with a laptop balanced on his knees can crank up the temperature of his scrotum to levels that aren't good for sperm.

So between the heat and the radiation from today's electronic devices, testicles would seem to be hard-pressed.

However, Dr Robert Oates, the president of the Society for Male Reproduction and Urology, has managed to father two kids despite having both a laptop and an iPad. He told Reuters Health he doesn't believe laptops are a significant threat to male reproductive health.

Remarking on the new study, he said: ‘This is not real-life biology, this is a completely artificial setting. ‘It is scientifically interesting, but to me it doesn't have any human biological relevance.’

He added that so far, no study has ever looked at whether laptop use has any influence on fertility or pregnancy outcomes.

‘Suddenly all of this angst is created for real-life actual persons that doesn't have to be,’ said Oates, also of Boston Medical Center. He added: ‘I don't know how many people use laptops on their laps anyway.’

According to the American Urological Association, nearly one in six couples in the U.S. have trouble conceiving a baby, and about half the time the man is at the root of the problem.

While the impact of modern technology is still murky, lifestyle does matter, researchers say.

Earlier this month, a report in Fertility And Sterility showed that men who eat a diet rich in fruit and grains and low in red meat, alcohol and coffee have a better shot at getting their partner pregnant during fertility treatment.


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