Artist’s rendition of astronauts on Mars. (NASA)

Traveling into deep space could accelerate the onset of Alzheimer’s disease, an incurable form of dementia, according to a new report.

The NASA-funded study assessed how cosmic radiation would impact the astronauts throughout their trip in deep space. The effect of cosmic radiation on the human body has been a  concern for the US space agency as it plans manned missions into deep space, such as one to a distant asteroid in 2021, and another to Mars in 2035.

Earth’s magnetic field usually keeps us, and those in low Earth orbit, safe from the perils of cosmic radiation. However, beyond Earth’s protective magnetic fields, space travelers are exposed to a constant barrage of radiation.

With adequate warning, such as in the case of solar flares, steps can be taken to protect astronauts from dangerous forms of radiation. However, other forms of cosmic radiation, which occur without warning, cannot be blocked as effectively.

“Galactic cosmic radiation poses a significant threat to future astronauts,” said M. Kerry O’Banion,  a professor in the University of Rochester Medical Center (URMC) and senior author of the study. “The possibility that radiation exposure in space may give rise to health problems such as cancer has long been recognized. However, this study shows for the first time that exposure to radiation levels equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer’s disease.”

Artist’s illustration of the shape and function of the Earth’s magnetic field that protects us from harmful cosmic radiation (NASA)

In the past,  scientists studied the impact of cosmic radiation on a living being’s cardiovascular and musculoskeletal systems, as well as potential risks of contracting various forms of cancer.But the new study,  published in  PLOS ONE, examined the possible effects of space radiation on neurodegeneration, a gradual loss of brain structure or function.

For this study, researchers wanted to find out what role, if any, cosmic radiation plays in accelerating the biological and cognitive indicators of Alzheimer’s disease, especially in those  predisposed to developing the illness.

They specifically wanted to learn more about the impact of radiation from high-mass, high-charged (HZE) particles, which come in many forms and travel through space with the force of exploding stars.

Instead of examining hydrogen protons, which are produced by solar flares, the researchers decided to study iron particles. They say HZE particles, such as iron, when combined with their high rate of speed, are able to go through solid objects, like a spacecraft’s walls and protective shielding.

“Because iron particles pack a bigger wallop, it is extremely difficult, from an engineering perspective, to effectively shield against them,” said O’Banion. “One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.”

Brain affected by Alzheimer’s Disease (left) vs normal brain (right) – (US Dept of Veterans Affairs)

The researchers exposed mice to various doses of radiation, including levels that would be similar to what astronauts would experience during deep space voyages.To evaluate the cognitive and biological impact of the radiation exposure, the mice were then put through a series of experiments in which they had to recall objects or specific locations. Researchers observed that the radiation- exposed mice were much more likely to fail these tests, suggesting neurological impairment, earlier than the symptoms would typically appear.

Along with symptoms of neurological damage, the researchers found that the mice’s brains also showed signs of vascular changes and had a greater than usual buildup of beta amyloid, the protein “plaque” that gathers in the brain and is one of the characteristics of Alzheimer’s Disease.

“These findings clearly suggest that exposure to radiation in space has the potential to accelerate the development of Alzheimer’s disease,” said O’Banion. “This is yet another factor that NASA, which is clearly concerned about the health risks to its astronauts, will need to take into account as it plans future missions.”

British scientists have found you can lose weight without dieting – by replacing high-fat foods with their low-fat counterparts.

Writing in the British Medical Journal,  researchers from the University of East Anglia found that people who switched out high-fat foods with low-fat substitutes lost about 1.6 kg over six months without any additional dieting.

They also found lowering fat in your diet provides additional health advantages, such as lowering blood pressure and bad cholesterol levels.

The researchers believe their findings could play a role in dietary recommendations to help in the worldwide battle against obesity. The WHO and other public health organizations say obesity is a major risk factor for high blood pressure, cardiovascular disease, diabetes, some cancers and musculoskeletal disorders, such as the highly disabling degenerative disease of the joints, osteoarthritis.

A display of high fat foods such as cheeses, chocolates, lunch meat, french fries, pastries, doughnuts, etc. (Photo: US National Cancer Institute)

Looking to update its guidelines on total fat intake, the WHO recently commissioned a study to evaluate the relationship between the amount of fat and fatty products  consumed in daily diets and various indicators of body fatness such as total weight, waist size and/or body mass index (BMI).

For their study, the researchers evaluated 33 trials in North America, Europe and New Zealand, involving 73,589 participants of various ages and states of health.

Researchers compared the waistline measurements and weight of participants who ate a reduced-fat diet with those whose diet included the usual amounts of fat for at least six months.

Along with the loss of 1.6 kg of bodyweight, they also found that the participants reduced their total BMI by 0.56kg/m² – kg per square meter -and cut their waist circumference by 0.5cm.

Nutritionists recommend foods with protein (eggs/lean meat), whole grains, and fruits (or vegetables) for a healthy breakfast (Photo: Kenji Ross via Flickr/Creative Commons)

Wondering if the weight reduction by those in the group that consumed few fats was due in part to the additional time, attention and support they received, compared to those in the normal fat intake group, researchers looked to studies where both groups were given equal time and attention and found that the weight reduction did not disappear suggesting that the weight loss was really due to lower fat intake.

“The effect isn’t dramatic, like going on a diet. The research specifically looked at people who were cutting down on fat, but didn’t aim to lose weight, so they were continuing to consume a normal amount of food,” said Dr. Lee Hooper, who led the research. “What surprised us was that they did lose weight, their BMI decreased and their waists became slimmer. On top of this, they kept their weight down over at least seven years. There isn’t a specific goal, the more fat you cut down, the more your weight falls.”

Illustration of the interior of ’55 Cancri e’ — an extremely hot planet with a surface of mostly graphite surrounding a thick layer of diamond, with a molten iron core at the center. (Image: Haven Giguere)

Scientists have found a planet outside of our solar system which could be a true diamond in the rough.

This gem of a planet is twice Earth’s size, according to the US-Franco team that found it, and its surface appears to be covered in graphite and diamond.

Researchers estimate that at least one-third of the new planet’s mass could be diamond.

The gemstone planet, called ’55 Cancri e’, has a radius twice that of Earth’s and a mass that’s eight times greater, making it a “super-Earth.”  The planet is one of five found orbiting ’55 Cancri’, a sun-like star about 40 light years from Earth.  Located in the constellation of Cancer, scientists say the star can be seen with the naked eye.

Astronomers first spotted the planet last year as it was transiting its star, which allowed them to measure its radius for the first time.  Using that information, along with their most recent estimate of its mass, researchers used computer modeling to speculate on the chemical composition of the planet.

Previous research revealed that the host star, 55 Cancri, has more carbon than it does oxygen, leading the US-French team to confirm that significant amounts of carbon and silicon carbide, with only a small amount of water ice, were available during the planet’s formation.

Star map showing the planet-hosting star 55 Cancri in the constellation of Cancer. The star is visible to the naked eye. (Image:Nikku Madhusudhan using Sky Map Online)

Astronomers initially assumed the diamond planet’s chemical composition was similar to Earth’s and that 55 Cancri e contained a substantial quantity of super-heated water.  However, according to Yale University researcher Nikku Madhusudhan, the new research suggests the planet has no water at all and is primarily made up of carbon – such as graphite and diamond – as well as iron, silicon carbide, and, possibly, some silicates.

The identification of a carbon-rich super-Earth means scientists can no longer assume that all distant rocky planets have chemical elements, interiors, atmospheres or biologies similar to Earth, according to Madhusudhan.

Which means there could be other gemstone planets out there just waiting to be discovered.

Do you ever wish you could take a pill that would erase a really traumatic memory or at least help take the emotional pain away?

A recent study suggests researchers might be on to something like that.

The team from the Centre for Studies on Human Stress at the University of Montreal says the drug metyrapone could help those suffering from conditions such as Post-traumatic stress disorder.

On the “Science World” radio program this weekend, we talk with the study’s lead author, Marie-France Marin.

She tells us that metyrapone doesn’t actually eliminate the memory, but it does reduce the brain’s ability to re-record the negative emotions associated with bad memories.

Listen to the interview here… 

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Other stories we cover on the “Science World” radio program this week include:

• A somber anniversary as AIDS hits the 30-year mark
• World health experts now say cell phones might cause cancer
• China rejects Google claims that hackers in that country spied on email accounts
• How technology is helping to improve access to health care in Senegal
• Who would win a chess match in an Earth versus Space contest