Health News Worldwide
1. New hope for wrinkles
A new anti-aging ingredient developed by Australian researchers is expected to be available in skin products next year. The new additive - gamma glutamyl cysteine (GGC) - is a precursor for an effective antioxidant known as glutathione, which has a broad range of potential health benefits.
Glutathione is the body's key defense for detoxifying harmful compounds implicated in cancer, diabetes, aging along with other diseases and degenerative conditions.
After nine years in development, researchers Dr Wallace Bridge and Dr Martin Zarka, of the University of New South Wales have established a new, cost-effective process for manufacturing GGC.
The process has been licensed to pharmaceutical company, Biospecialties Australia. A newly-expanded manufacturing plant at Newcastle, New South Wales, will produce GGC.
It is expected that GGC will be used as an active ingredient in foods, health care, toothpastes, dietary supplements and cosmetics as well as in skin repair anti-aging creams. Natural dietary sources of GGC are available, including milk whey protein and garlic. However, GGC is present only in relatively dilute concentrations. This new, pure GGC product will potentially allow for more efficacious dosages and product formulations. Given the rapidly increasing interest in glutathione, it is likely a pure GGC supplement would have significant market potential.
A moderate exercise program may reduce the incidence of colds. A study published in the November issue of The American Journal of Medicine, led by researchers at Fred Hutchinson Cancer Research Center, found that otherwise sedentary women who engaged in moderate exercise had fewer colds over a one year period than a control group.
Subjects in a group of 115 overweight and obese, sedentary, postmenopausal women were randomly assigned to either a moderate exercise program (45 minutes per day, five days per week and comprised of mostly brisk walking) or to a once-weekly 45 minute stretching session. Both the exercisers and the stretchers filled out questionnaires every 3 months on the number of episodes of allergies, upper respiratory tract infections (colds and flu) and other infections. Subjects were taught how to distinguish various forms of infections and were followed for one year.
Over 12 months, the risk of colds decreased modestly in exercisers and increased modestly in stretchers. In the final three months of the study, the risk of colds in stretchers was more than 3-fold higher than that of exercisers. More stretchers than exercisers had at least one cold during the 12-month study period (48.4% vs 30.2%), and among women reporting at least one cold, stretchers tended to report colds more frequently than exercisers.
Senior author Cornelia M. Ulrich, PhD, of the Hutchinson Center, writes, "Our trial is the first to report on the effects of a year-long, moderate-intensity exercise training program on the incidence of upper respiratory tract infections. Although we did not find an effect overall on upper respiratory tract infections, our study suggests that moderate-intensity training can reduce the risk of colds in postmenopausal, nonsmoking, overweight or obese women. This finding is of clinical relevance and adds a new facet to the growing literature on the health benefits of moderate exercise." 3. Do low-fat foods make us fat?
Recent Cornell studies in movie theatres, holiday receptions, and homes showed people eat an average of 28% more total calories when they eat low-fat snacks than regular ones. "Obese people can eat up to 45% more," reports lead researcher Brian Wansink (Ph.D.), in the book, Mindless Eating: Why We Eat More Than We Think.
"People don't realize that low-fat foods are not always low-calorie foods," says Wansink. Fat is often replaced with sugar. Low-fat snacks are an average of 11% lower in calories, but people wrongly believe they are around 40% lower.
In one study, two groups of people attending a holiday open-house were given identical regular chocolates that were labeled as either "Regular" or as "Low-fat." People served themselves an average of a third more of the candies, which would have translated into 28% more calories if they had actually been low-fat. A second study showed this is because "people believe they will feel less guilty eating the low-fat foods, so they tend to overindulge, says Pierre Chandon, co-author and marketing professor at INSEAD in France. Fat is often replaced with sugar.
The complete set of research studies, published in the November issue of the Journal of Marketing Research, was cited by the Economist as one of two significant noteworthy studies published that month. It is titled, "Can ‘Low-Fat' Foods Lead to Obesity""
For policy makers and companies, the message is that new "low-fat" foods are unlikely to solve the obesity solution. People are very likely to over eat a low-fat foods – even if they don't like them as much as the regular versions.
For dieters, there's also clear message. As Wansink advises in the book Mindless Eating, "Stick with the regular version, but eat a little bit less. It's better for both your diet and your taste buds." 4. Teens Who Take Multivitamins Have Healthier Lifestyles
Teenagers who take a daily multivitamin supplement have a healthier diet and lifestyle than those who don't take vitamins, reports a study in the December Journal of the American Dietetic Association.
As part of the Child and Adolescent Trial for Cardiovascular Health (CATCH), the researchers analyzed data on height, weight, diet, and health behaviors for more than 2,500 U.S. high school seniors. Their goal was to discover whether teens who took vitamin supplements differed in terms of diet, exercise, and other health habits. The lead author was Lindsay Reaves of University of Minnesota School of Public Health.
Twenty-five percent of the teens reported taking a daily multivitamin supplement. Females were more likely to take vitamins than males, and whites more likely than minority members.
Vitamin use was related to some important differences in lifestyle behaviors, with vitamin users having healthier lifestyles. Adolescents who took vitamins had a lower rate of smoking, 29 vs 33 percent; and were less likely to be overweight, 31 vs 37 percent.
Teens who took vitamins were also more physically active, including higher rates of participation in team sports and other organized sports. Vitamin use was also linked to a lower rate of television watching—less than 60 percent of vitamin users watched an hour of TV per day, compared with 70 percent of nonusers. The differences remained significant after statistical adjustment for other factors.
Taking vitamins was also associated with a healthier diet, as reflected by an overall "food index score." Adolescents who took vitamins actually consumed more calories, but got more of their calories from carbohydrates and protein and less from fats. Vitamin users ate more fiber; had more daily servings of whole grains, fruits and juices, and vegetables; and ate more fish. Although teens who took vitamins, had more desserts, they ate fewer fried foods and drank fewer soft drinks.
The American Dietetic Association recommends a diet including a wide variety of foods as the best strategy for optimal health and lower risk of chronic disease. Like adults, many adolescents take regular vitamin and mineral supplements. The new study is one of the first to look at the relationship between vitamin supplement use among teens and diet and lifestyle factors such as physical activity and overweight.
"Adolescents who use multiple vitamin supplements have healthier dietary and lifestyle behaviors than non-users," the researchers write. They remind dietitians to ask teens about vitamin use—what types of supplements they take, how often, and why. Teens with a healthier diet are more likely to take vitamins, and thus are probably at lower risk of having poor nutritional status.
However, "Supplements are not substitutes for healthy dietary patterns," the researchers conclude. "Adolescents should be encouraged to adopt such healthy patterns, rather than rely on dietary supplementation for adequate nutrient intake." 5. Exercise when young may reduce risk of fractures later in life.
When kids are running and jumping, they aren't just having fun, according to IUPUI researchers.
Running and jumping during childhood is more than child's play; it provides lifelong benefits for future bone health and appears to reduce the risk of fractures later in life according to a Journal of Bone and Mineral Research study by Indiana University-Purdue University Indianapolis (IUPUI) researchers. The study is now available in an advance online edition of the journal and will appear in a print edition in 2007.
"Our study demonstrates that exercise when young may reduce the risk of fractures later in life, and the old exercise adage of 'use it or lose it' may not be entirely applicable to the skeleton," said the study's principal investigator, Stuart J. Warden, assistant professor and director of research in physical therapy at the Indiana University School of Health and Rehabilitation Sciences at IUPUI.
Researchers exercised the right forearms of 5-week-old female rats for a few minutes three times a week for seven weeks. The left forearms were not exercised. Bone quantity and structure of the rats' right and left forearms were assessed before and after exercise. Researchers did not exercise the rats for the next 92 weeks -- virtually their entire lifespan. At that point, their forearm bones were assessed again for bone quantity and structure, as well as strength.
All procedures were performed following approval of the Institutional Animal Care and Use Committee of Indiana University.
"We knew that exercise increases bone size and strength, and that the skeleton is most responsive to exercise during the crucial growing years around puberty when you reach adult size and strength," Warden said. "We also knew that bones are not as responsive to exercise when you are older."
What was not known, however, was if the skeletal benefits of exercising while young would last a lifetime, Warden said. In other words, he said, "can you use activity while young to offset the risk of osteoporosis, or the risk of bone fractures, later in life."
The study determined the answer to that question is, "Yes," Warden said.
The researchers found that the rats retained all of the skeletal exercise benefits they obtained while young even though they hadn't exercised for the rest of their lives, Warden said.
"We found the exercise resulted in a lifetime increase in bone size in the right forearms of the rats and the bones of the left forearms never caught up in size," he said.
How big a bone is determines how resistant it is to bending, or how strong it is, he said.
As humans age, bone loss occurs from the inside surface of the bone outward, Warden noted. Exercising while young lays down additional outside layers of bone. This results in a bigger bone than otherwise would be the case.
"With more bone layers on the outside, you have more bone to lose," Warden said.
By making the right forearm bones bigger during growth in their study, the researchers found these bones to be stronger, or more resistant to fracture, than left forearm bones despite exercise being ceased a lifetime ago.
The study demonstrates the importance of childhood exercise that stimulates the skeleton, like basketball or jumping, Warden said. Short periods of exercise several times a week are all that is needed to stimulate bone development in children, he added.
The message to older adults, however, remains the same. Even though the best time to gain lifetime bone health benefits is while people are young, exercising when people are older is essential to maintain bone mass and balance, as well as maintain aerobic fitness, all of which aid in reducing the risk of low-trauma (osteoporotic) fractures associated with aging.
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