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.”

The amount of space junk floating around the Earth grows every year, and increasingly can pose risks to spacecraft orbiting the planet.

This computer generated graphic provided by NASA shows objects in Earth orbit that are currently being tracked. Space junk has made such a mess of Earth’s orbit that experts say we may need to finally think about cleaning it up. (AP)

In the United States, NASA’s Orbital Debris Program (ODP) at the Johnson Space Center in Texas, keeps an eye on the ever-expanding junkyard of space.

“We define orbital debris as any man-made object orbiting the Earth that is no longer serving a useful purpose,” says Gene Stansbery, project manager for the ODP. “That can be anything from very large rocket bodies and dead satellites that are no longer useful, all the way to very tiny particles that are eroded from the painted surfaces of spacecraft or rockets, the entire size range.”

In the weightless and friction-free environment of orbit, it’s not so much the size of all this junk floating in the Earth’s orbit, but also the speeds at which it travels, according to Stansbery.

“If you look at orbital velocities and the average collision velocity, you’re talking on the order of 11 kilometers a second,” he says. “So even a small paint fleck can damage a sensitive component for spacecraft.”

An example occurred during STS 7, when a window for the space shuttle had to be replaced for the first ever time after being damaged by a .2 millimeter paint fleck. If that level of damage can be caused by a particle that small, one can imagine the threat posed by larger orbiting refuse.

Given that space exploration has been an on-going venture since the 1950s, there’s a lot of old stuff circling the planet, and much of it can pose serious risks.

“The Department of Defense has a world-wide network that can track objects down to about 10 centimeters in size in low Earth orbit,” says Stansbery. “For those objects, there’s about 22,000 that they’re tracking. You go down to about one centimeter and larger, you’re talking about 500,000, and if you get smaller than that and you’re talking into the millions.”

Some of that stuff, especially in low-Earth orbit, will eventually fall back to the planet, much of it burning up on re-entry. However, for junk found at higher altitudes, around 1,000 kilometers or so, Stansbery says it could remain in orbit for decades, maybe even hundreds of years. For altitudes even higher than that, junk could remain for centuries…or longer.

A white arrow points to damage on a piece of a solar array from the Russian space station Mir. The array had been damaged by a miniscule piece of space junk. (AP)

Major collisions are rare, but they do happen. On Feb. 10, 2009, two large satellites, the Iridium 33 and the Kosmos 2251, collided at a speed of about 42,000 kilometers per hour. The collision spread about 1,000 pieces of debris capable of being tracked across the skies, where much of it remains.

In March of this year, one of those pieces came uncomfortably close to the International Space Station. So close, in fact, that as a precaution, the ISS’ six-member crew waited for a time in the Soyuz emergency exit capsule, just in case a collision occurred and they had to abandon ship.

More worrisome, says Stansbery, is that the crew only had 24 hours notice of the possible collision. “Unfortunately, that is too short a time to plan a re-avoidance maneuver for the space station,” he says.

The threat posed by space junk isn’t new; space scientists have been concerned about it since the 1970s. However, with more rockets taking off, more satellites in the sky, and more spacecraft – such as from China or private firms like SpaceX and Blue Origin – the skies are getting more crowded all the time.

This week on VOA’s “Science World” radio program, you can hear the complete interview with Gene Stansbury on space junk, as well as other features on the science behind children’s snack food choices, the lingering effects of the Gulf of Mexico oil spill on corral communities, and a new web-based computer program that helps doctors save lives. Take a look at the right hand column for scheduled times.

(Written by Doug Bernard,  Digital Frontiers Editor)

After being injected with an opiate-like chemical produced in the human brain, laboratory rats ate twice the normal amount of sweet fatty food. (Photo: Alexandra Difeliceantonio)

Are you on a diet but  having a hard time resisting that candy bar or cheeseburger?  The problem  might really be in your head.

Researchers have found that an opium-like chemical produced in the brain might explain why some people overeat sweet and fatty foods.

“This means that the brain has more extensive systems to make individuals want to over consume rewards than previously thought,” says Alexandra DiFeliceantonio of the University of Michigan, Ann Arbor, who led the study. “It may be one reason why over-consumption is a problem today.”

The researchers found  a region of the brain called the neostriatum, located near the middle and front of the brain, which is best known for  controlling motor movements. It also produces the opiate-like chemical called enkephalin, which  DiFeliceantonio says sparks and intensifies the urge to consume pleasant rewards.

To make their findings, DiFeliceantonio and her team injected some of the morphine-like drug directly into the neostriatum of their lab rats.  After the injections, the rats were fed candy-coated chocolate. The rodent test subjects ate more than twice the number of chocolates than they would normally have eaten.

The researchers also found the levels of enkephalin – the opium-like chemical manufactured by the neostriatum – surged when the rats began to eat the  candy. And while the enkephalins, or comparable drugs, didn’t actually make the rats enjoy the candy more, they did increase their cravings and compulsion to eat them.

“The same brain area we tested here is active when obese people see foods and when drug addicts see drug scenes,” says DiFeliceantonio. “It seems likely that our enkephalin findings in rats mean that this neurotransmitter may drive some forms of overconsumption and addiction in people.”

DiFeliceantonio says the findings  reveal a lot about our tendency to binge and could eventually lead to the development a drug that  blocks the impulse to overeat.