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.”

Eating breakfast may help keep you from getting fat and making poor food choices (Photo: Angela de Março via Flickr/Creative Commons)

Skipping breakfast sets the brain up to make poor food choices later in the day, according to a new study.

Scientists from the MRC Clinical Science Centre at London’s Imperial College, compared the brain scans and eating patterns of people both after eating breakfast and when they were fasting.

They found that those who avoid breakfast may overeat throughout the rest of the day, often choosing high-calorie or junk food over healthier selections.

The researchers studied the magnetic resonance images (MRIs) of 21 volunteer test subjects who didn’t eat anything before coming in for their tests.  On one those visits, the volunteers were first given a 750-calorie breakfast before the researchers ran the MRI scans.

On another visit to the research center, the test subjects weren’t fed any breakfast, but were always served lunch after each scanning session.

“Through both the participants’ MRI results and observations of how much they ate at lunch, we found ample evidence that fasting made people hungrier, and increased the appeal of high-calorie foods and the amount people ate,” said Dr. Tony Goldstone, who led the study.

Researchers believe the brain’s orbitofrontal cortex (highlighted in this MRI image) might play a key role in influencing food choices. (MRI Image: Paul Wicks via Wikimedia Commons)

While examining the MRIs of volunteers who hadn’t eaten breakfast, the scientists found a variation in the pattern of activity in the orbitofrontal cortex, that’s the area of the brain located right above the eyes that can affect decisions concerning the appeal and reward value of food.

When participants who were fasting or didn’t eat any breakfast were shown pictures of high-calorie food,  the MRIs showed that that portion of the brain was “activated,” a reaction less strong when they had eaten breakfast.

After studying and comparing the MRI scans over a period of time, the researchers were able to use the brain scans to predict which of their test subjects would be the mostly likely to respond strongly to high-calorie foods.

To Goldstone and his colleagues, these findings suggest  the orbitofrontal cortex may play a key role in influencing people in making their food choices.

They also say their research complements previous studies that show fasting may not be the best way to lose weight, since doing so tends to create a “bias” in the brain that makes us seek a high-calorie food reward.

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)

Eating a healthy breakfast doesn’t necessarily mean sitting down to a formal meal or even eating traditional breakfast foods like cereals or eggs.

You can mix up the food items you want to eat for breakfast and that could also include eating some of those tasty leftovers from the previous night’s dinner.

Here are some tips and suggestions on healthy breakfast choices from the Academy of Nutrition and Dietetics:

• Include some lean protein, such as eggs, cheese, deli meat, peanut butter, Canadian bacon or yogurt
• Pair that lean protein with a whole-grain carbohydrate food, such as a whole-grain cereal, bread, waffles, pancakes or oatmeal
• Be sure to include fruits and vegetables to your breakfast  Top off yogurt with some fruit or chop up some veggies to add to your omelet
• To save time, nutritionists suggest prepping breakfast the night before

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.

Turns out obesity isn’t just a health issue;  all of that overeating could seriously cut into the future world food supply.

According to a new study from Great Britain, if the current worldwide obesity epidemic continues unabated, maintaining enough food to feed the world could actually become a much more serious challenge.

Right now, the world’s population is over seven billion, and growing.  The more people there are, the more food and resources are needed.

According to the London School of Hygiene & Tropical Medicine,  the weight of the human population should be taken into consideration – in addition to the number of people in the world -  when determining future food security and environmental sustainability.

Using data from various studies, researchers determined the world’s adult population weighs 287 million metric tons, or 287 billion kilograms.

Separately, we each weigh an average of 62 kilograms, but that average varies from country to country.

Researchers estimate 15 million of that 287 metric tons is due to those who are overweight, while 3.5 million metric tons are due to obesity.

North Americans have the highest body mass of any continent, according to the study, with an average body mass of 80.7kg.

While North America has only about six percent of the world’s population, it contributes 34 percent of the world’s biomass.

Asians, on the other hand, whose average weight is 58 kilograms, make up around 61 percent of the world’s population, but they’re only responsible for roughly 13 percent of the world’s biomass.

Among nations,  the United States came in as the “heaviest” country, while Eritrea was the “lightest”.

The researchers also looked at how those who are overweight and obese impact the total weight and averages.

Keep in mind that there is a difference between being overweight and obese.

You’re considered to be overweight when you weigh more than the weight that is appropriate for your height and bone structure or have a Body Mass Index (BMI) of 25 or greater.

If you have BMI of 30 or more, medical experts consider you to be obese.

Experts say that up to half of all food that is eaten is burned up by various physical activities.  But as your weight rises, your energy requirements increase as well, because it takes more energy to move a heavy body.

Even when at rest, those who have a bigger body mass burn more energy.

So, the bigger you are, the more energy you’ll need; the more energy you need means you must eat more; the more food eaten by a growing world population could  then, in turn, impact affect food supplies and future food security.

Soybeans being harvested (Photo: Jake was here via Wikimedia Commons)

The domino effect of a heavier populace can also affect environmental sustainability.  Because in order to feed, cool or warm and transport a heavier population, more natural resources, such as fossil-fuels, will be needed and consumed.

Sarah Walpole, a practicing medical doctor who co-authored the study,  worries people from developing nations, who tend to be thinner than those in developed countries, will be most at risk of food insecurity.

“If our global consumption for food or our demand for food are increasing, it going to be those poor populations that feel the impact most,” she says.

One of the areas researchers want to study next is the impact the global child population has on the world’s total human biomass.

Dr. Walpole joins us on this week’s radio edition of “Science World.”  Check out the right column for scheduled air-times or listen to the interview with Dr. Walpole below.

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

• Kenyan conservationists preserve endangered sea turtles
• Ocean levels rising faster on US coasts than elsewhere in the world
• 2009 swine flu deaths were much higher than first reported
• Crisis mapping helps first-responders do their jobs in times of disaster
• Gastric Bypass Surgery, Alcohol Not a Good Mix for Some

Little girl snacks on cotton candy (Photo: AP Photo/Carolyn Kaster)

Attitudes, relationships, intentions and personal behavior control are all factors which influence whether children reach for junk food rather than opting for healthy snacks, such as fruit and vegetables.

A University of Cincinnati study finds intentions are a major factor behind a child’s snack choices. This is driven by several variables, such as the child’s attitude toward eating healthy or unhealthy foods, as well as the social or peer pressure the child feels.

While we all love to snack from time to time, we don’t always go for the healthier choice, opting instead for junk food, which is  high in calories but low in nutritional value.

Children are no different when it comes to snacking, but as awareness of childhood obesity continues to rise, researchers and public health officials are increasing their scrutiny of children’s eating habits, including what they choose to eat as snacks.  Zeroing in on the problem of obesity in children is an important public health concern and could help prevent future health threats such as diabetes and heart disease.

The study points to the strong influence of parents, teachers and other adults kids know and trust.  If a parent or teacher has good snacking or eating habits, this can influence what the child eats well, too.

The amount of control children feel they have over snacking is another factor influencing snack choice; in other words, if they are given the freedom to choose their own snacks rather than having them already selected for them.

Published in the International Quarterly of Community Health Education, the study looked at the eating and snacking behaviors of 167 fourth- and fifth-grade elementary schoolchildren in the Cincinnati, Ohio, area over a 24-hour period.

The study did find that snacking was a major part of the children’s caloric intake, about 300 calories a day from foods like chips, candy and cookies.  These so-called high-calorie, low-nutrition foods made up around 17 percent of the kids’ daily caloric needs.  Only 45 calories of the study group’s daily intake came from healthy snacks like fruits and vegetables.

Healthy choice - boy eating an apple (Photo: AP Photo/Jacqueline Arzt)

Researchers also examined whether children thought selecting lower-calorie snacks over the high-calorie versions was a good idea; how confident there were in knowing how to pick the lower-calorie snack foods; and whether they were influenced or felt pressure from their parents, teachers or friends in picking the lower-calorie snacks.

The demographics of the children in the study group were varied and included a mix of boys and girls, Caucasians, African-Americans, Hispanics and Asian-Americans.

There are also differences in snack choices along the lines of gender and ethnicity.  Girls in the study tended to eat more of the high-calorie snacks, taking in an average of 348.3 calories a day, while boys consumed around 238.8 calories each day.

African-American children ate the smallest amount of high-calorie snacks, at 221.6 calories a day. Hispanic children consumed 297.6 snack calories daily, followed by Caucasian children who ate 282.3 calories a day. Asian-American children who took in about 280.8 calories a day.

Among the ethnic groups measured, the study also finds that both Hispanic and Asian-American children consume more of the healthier snacks, such as fruit and vegetables, than both Caucasian and African-American children.

The study’s authors say their research suggests more care and concern should be given to what foods children choose for their snacks, because they’re relatively cheap and easy for children to buy.

You can listen to what Dr. Paul Branscum, one of the study’s authors, says about the study, what it revealed and how important it is to the future health of our children to pay attention to their choices of snack foods and encourage healthier eating habits.

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