Archive for June, 2010

Herb shows no added benefits for women’s bones

Wednesday, June 30th, 2010

Exercise may help older women maintain their bone density, but adding the supplement black cohosh to the routine does not bring any extra benefits, a new study suggests.

Researchers found that among 128 postmenopausal women they studied for one year, those who were randomly assigned to regularly exercise generally maintained their bone density. In contrast, women who were assigned to a “wellness” group that got only light, infrequent exercise showed a decline in their bone density, on average.

But while exercise appeared to help women hang on to their bone mass, the herb black cohosh showed no added effects. Among exercisers, those who were randomly assigned to take the supplement each day showed no bone-density advantage after one year.

Black cohosh extracts are marketed as a “natural” form of hormone replacement therapy and most commonly used to treat hot flashes and other symptoms of menopause. Some lab research, but not all, suggests the herb may have estrogen-like activity in the body.

The new study appears to be the first to look at the effects of black cohosh on bone density, according to lead researcher Michael Bebenek of the University of Erlangen, in Germany.

While in theory, a substance with estrogen-like effects could protect women’s bone density, the benefits of black cohosh for bone health is “still doubtful,” Bebenek told Reuters Health in an email.

He and his colleagues report the findings in the medical journal Menopause.

For their study, the researchers recruited 128 women who had gone through menopause within the past one to three years.

They randomly assigned 86 women to an exercise program that interspersed six weeks of higher-intensity activities designed to protect bone mass — like high-impact aerobics and strength training — with 10 weeks of more-moderate exercise designed to improve heart health. The latter included activities like brisk walking and step aerobics.

Half of the exercisers also took a 40-milligram black cohosh supplement each day.

The remaining 42 women were assigned to a “wellness” group that performed low-intensity activities, like light walking, stretching and balancing exercises, for one hour a week.

After one year, women in both exercise groups showed no significant change in bone density at the spine, while those in the wellness group showed a 2 percent decline, on average. Exercisers had a slight increase in bone mass at the hip — about 0.5 percent — versus an average dip of 0.6 percent in the wellness group; that difference was not, however, significant in statistical terms.

The researchers found no significant bone-mass differences between exercisers on black cohosh and those who did not take the supplement.

Bebenek’s team also looked for any changes in the study participants’ Framingham risk scores — an estimate of a person’s odds of suffering a heart attack or dying from heart disease in the next 10 years. The score is based on age, smoking history, blood pressure and cholesterol levels and whether a person has diabetes.

Overall, the researchers found no clear effects of exercise or exercise-plus-black-cohosh on the women’s risk scores.

At the end of the study, women in the exercise-only group were estimated to have a 6 percent chance of suffering a heart attack or dying from heart disease in the next 10 years; that risk was 7 percent and 7.8 percent in the black cohosh and wellness groups, respectively. However, the differences in the groups’ score changes over time were not significant in statistical terms.

The bottom line, according to the researchers, is that the study “again clearly demonstrated” the positive effects of exercise on postmenopausal women’s bones. Whether black cohosh has any bone-health benefits, however, remains in question.

High Fructose Corn Syrup Linked to Liver Scarring

Sunday, June 20th, 2010

New research links consumption of high-fructose corn syrup, the extremely popular sweetener that shows up in food products from ketchup to jelly, to liver damage in people with non-alcoholic fatty liver disease.

It’s not clear if the sweetener directly causes liver scarring, also known as fibrosis, but those who consumed more of the sweetener appeared to have more liver scarring, according to the report released online in advance of publication in an upcoming print issue of the journal Hepatology.

“We have identified an environmental risk factor that may contribute to the metabolic syndrome of insulin resistance and the complications of the metabolic syndrome, including liver injury,” Dr. Manal Abdelmalek, associate professor of medicine in the division of gastroenterology/hepatology at Duke University Medical Center and leader of a team of scientists behind the new research, said in a university news release.

The researchers examined the medical records of 427 adults with non-alcoholic fatty liver disease (NAFLD), along with questionnaires the patients completed about their diets.

Only 19 percent of adults with non-alcoholic fatty liver disease said they never drank beverages containing the sweetener; 29 percent did so every day, the investigators found.

“Non-alcoholic fatty liver disease is present in 30 percent of adults in the United States,” Abdelmalek said in the news release. “Although only a minority of patients progress to cirrhosis, such patients are at increased risk for liver failure, liver cancer, and the need for liver transplant. Unfortunately, there is no therapy for non-alcoholic fatty liver disease. My hope is to see if we can find a factor, such as increased consumption of high-fructose corn syrup, which if modified, can decrease the risk of liver disease.”

Representatives of the corn refining industry took issue with the findings, noting that the study involved a wide range of sources of fructose, not just beverages sweetened with high-fructose corn sugar.

Furthermore, “fructose has not been proven to be a cause of NAFLD in humans, and NAFLD subjects are compromised individuals with significant health problems which have very little to do with fructose intake,” according to a news release from the Corn Refiners Association released late Friday.

“Moreover, associative studies of this kind are widely judged to be of low scientific value when trying to establish cause-and-effect, data from studies like this that are dependent on recollection of the study subjects are notoriously imprecise, and these studies are full of confounding variables and exceedingly difficult to control,” the CRA added.

Hypoglycemia May Raise Risk of Death in ICU Patients

Thursday, June 10th, 2010

Mild to moderate hypoglycemia (low blood sugar) increases the risk of death in critically ill patients, a new study shows.

It included 4,946 critically ill patients at six medical centers in Australia, Japan and New Zealand. Of those patients, 1,109 experienced hypoglycemia while the remainder served as a non-hypoglycemic control group.

It had been believed that mild to moderate hypoglycemia was clinically unimportant. But this study found that patients with hypoglycemia had a death rate of 36.6 percent, compared with 19.7 percent for those without hypoglycemia.

“Even after the adjustment for insulin therapy or timing of hypoglycemic episode, the more severe the hypoglycemia, the greater the risk of death,” study co-investigator Dr. Rinaldo Bellomo, of Austin Health in Melbourne, said in a news release.

“Our results suggest that any tolerance of mild to moderate hypoglycemia by intensive care clinicians may be undesirable. In this regard, newer technologies such as continuous glucose monitoring in the ICU setting might help avoid hypoglycemia or identify it earlier,” Bellomo said.

The study appears in the issue of Mayo Clinic Proceedings.