Past News Items - July 2010
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In the News
Glucosamine Appears to Provide Little Benefit for Chronic Low Back Pain
Tart Cherry Juice May Be a Natural Solution for Insomnia
Cutting Carbs is More Effective Than Low-fat Diet for Insulin-resistant Women
Higher Levels of Vitamin B6, Common Amino Acid Associated With Lower Risk of Lung Cancer
Glucosamine Appears to Provide Little Benefit for Chronic Low Back Pain
Though glucosamine is widely used as a therapy for low back pain, a randomized controlled trial finds that patients with chronic low back pain (LBP) and degenerative lumbar osteoarthritis (OA) who took glucosamine for 6 months showed little difference on measures of pain-related disability, low back and leg pain, and health-related quality of life, compared to patients who received placebo, according to a study in JAMA.
Osteoarthritis affects more than 20 million people in the United States, a number that is expected to increase. Glucosamine is widely used as a treatment for OA, despite its controversial and conflicting evidence for effect, and is also increasingly taken by patients with LBP even though the evidence of its effectiveness remains inconclusive.
Philip Wilkens, MChiro, of Oslo University Hospital and University of Oslo, Norway, and colleagues investigated the effect of a 6-month intake of glucosamine in reducing pain-related disability by conducting a randomized, placebo-controlled trial with 250 patients older than 25 years of age with chronic LBP (for longer than 6 months) and degenerative lumbar OA. Patients took either 1500 mg of oral glucosamine (n = 125) or placebo (n = 125) daily for 6 months, with effects assessed after the 6-month intervention period and at 1 year. The primary outcome was pain-related disability as measured with the Roland Morris Disability Questionnaire (RMDQ). Secondary outcomes were numerical scores from pain-rating scales of patients at rest and during activity and a quality-of-life measure. Data collection occurred at the beginning of the trial and at 6 weeks, 3 and 6 months, and 1 year.
At the beginning of the trial, the average RMDQ score was 9.2 for the glucosamine group and 9.7 for the placebo group. The 6-month average RMDQ score was 5.0 for both the glucosamine and placebo groups, and 1-year score was 4.8 for the glucosamine group and 5.5 for the placebo group. No statistically significant difference in change between groups was found when assessed after the 6-month intervention period and at 1 year for RMDQ and for measures of LBP at rest, LBP during activity, and quality-of-life. Mild adverse events were reported in 40 patients in the glucosamine group and 46 patients in the placebo group.
The authors concluded that based on the results, it is unwise to recommend glucosamine to all patients with chronic LBP and degenerative lumbar OA.
Tart Cherry Juice May Be a Natural Solution for Insomnia
Drinking tart cherry juice daily could help reduce the severity of insomnia and time spent awake after going to sleep, according to a new study published in the Journal of Medicinal Food.
A team of University of Pennsylvania, University of Rochester, and Veteran’s Administration Center of Canandaigua researchers conducted a pilot study on the sleep habits of 15 older adults. The adults drank 8 oz of tart cherry juice beverage (CheriBundi, www.cheribundi.com) in the morning and evening for 2 weeks and a comparable matched juice drink with no tart cherry juice for another 2-week period. There were significant reductions in reported insomnia severity, and the adults saved about 17 minutes of wake time after going to sleep on average when drinking cherry juice daily compared to when they were drinking the other juice drink.
Ongoing sleep issues plague more than 40 million adults, and another 20 million experience occasional sleep disruptions, putting their health and well-being at risk and leaving many Americans on a quest for sleep solutions, according to the National Institutes of Health. Americans spend more than $84 million on over-the-counter sleep aids each year.
The researchers suspect tart cherries’ natural benefits could be due in part to their relatively high content of melatonin—a natural antioxidant in cherries with established ability to help moderate the body's sleep-wake cycle. Produced naturally by the body in small amounts, melatonin plays a role in inducing sleepiness at night and wakefulness during the day.
Russel J. Reiter, PhD, a biomedical scientist at the University of Texas Health Science Center, says while melatonin supplement pills have been heavily promoted as a sleep aid, foods such as cherries may be a better alternative for boosting the body’s supply of melatonin.
Melatonin is not only helpful for insomnia; research suggests it can be a powerful antioxidant, helping reduce age-related inflammation and fighting free radicals in the body. Beyond melatonin, cherries are packed with other powerful antioxidant compounds, including anthocyanins—the compounds responsible for cherries’ bright red color. A growing body of science indicates that cherries may help reduce inflammation, aid muscle recovery, and reduce risk factors of age-related conditions.
Cutting Carbs is More Effective Than Low-fat Diet for Insulin-resistant Women
Obese women with insulin resistance lose more weight after 3 months on a lower-carbohydrate diet than on a traditional low-fat diet with the same number of calories, according to a new study. The results were presented at The Endocrine Society’s 92nd Annual Meeting in San Diego.
“The typical diet that physicians recommend for weight loss is a low-fat diet,” said the study’s lead author, Raymond Plodkowski, MD, chief of endocrinology, nutrition, and metabolism at the University of Nevada School of Medicine, Reno. “However, as this study shows, not all people have the same response to diets.” People with insulin resistance, a common precursor for Type 2 diabetes, metabolize carbohydrates, or “carbs,” abnormally, which may affect their rate of weight loss. For them, the lower-carb diet is more effective, at least in the short term, according to Dr Plodkowski.
At 12 weeks, the study funded by Jenny Craig using prepared calorie-controlled meals as part of a behavioral weight loss program found that the insulin resistant women on a lower-carb diet lost 3.4 lbs more than those on a low-fat diet.
Forty-five obese women between the ages of 18 and 65 years participated in the study, and all had insulin resistance, as indicated by fasting blood levels of insulin. The researchers randomly assigned the women to either a low-fat or lower-carb diet. The groups did not differ significantly in average body weight, the authors reported. On average, women in the low-fat diet group weighed 213 pounds, and women in the other group weighed 223 pounds.
The composition of the low-fat diet was 60% of calories from carbs, 20% from fat, and 20% from protein. Although the lower-carb diet also had 20% of calories from protein, it had 45% from carbs and 35% from primarily unsaturated fats, such as nuts. Menus included a minimum of two fruits and three vegetable servings a day.
Use of prepared meals helped make the structured diets easier and more palatable for the dieters, according to Plodkowski.
Both groups lost weight at each monthly weigh-in, but by 12 weeks, the insulin-resistant group receiving the lower-carb diet lost significantly more weight, 19.6 lbs vs 16.2 lbs in the low-fat diet group—approximately 21% more on average.
Higher Levels of Vitamin B6, Common Amino Acid Associated With Lower Risk of Lung Cancer
An analysis that included nearly 400 000 participants finds that those with higher blood levels of vitamin B6 and the essential amino acid methionine (found in most protein) had an associated lower risk of lung cancer, including participants who were current or former smokers, according to a study in JAMA.
Previous research has suggested that deficiencies in B vitamins may increase the probability of DNA damage and subsequent gene mutations. Given their involvement in maintaining DNA integrity and gene expression, B vitamins have a potentially important role in inhibiting cancer development and offer the possibility of modifying cancer risk through dietary changes, according to the authors. They add that deficiencies in nutrient levels of B vitamins have been shown to be high in many western populations.
Paul Brennan, PhD, of the International Agency for Research on Cancer, Lyon, France, and colleagues conducted an investigation of B vitamins and methionine status based on serum samples from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study, which recruited 519 978 participants from 10 European countries between 1992 and 2000, of whom 385 747 donated blood. By 2006, 899 lung cancer cases were identified and 1770 control participants were individually matched by country, sex, date of birth, and date of blood collection.
After an analysis of the incidence rate of lung cancer within the entire EPIC cohort and adjusting for various factors, the researchers found a lower risk for lung cancer among participants with increasing levels of B6 (comparing the fourth vs first quartile of B6 levels). A lower risk was also seen for increasing methionine levels.
When participants were classified by median (midpoint) levels of serum methionine and B6, having above-median levels of both was associated with a lower lung cancer risk overall. A moderate lower risk was observed for increasing serum folate levels, although this association was restricted to former and current smokers and was not apparent in those who had never smoked.
“Our results suggest that above-median serum measures of both B6 and methionine, assessed on average 5 years prior to disease onset, are associated with a reduction of at least 50% on the risk of developing lung cancer. An additional association for serum levels of folate was present, that when combined with B6 and methionine, was associated with a two-thirds lower risk of lung cancer,” the authors wrote.
The researchers add that if their observations regarding serum methionine, B6, or both were shown to be causal, identifying optimum levels for reducing future cancer risk would appear to be appropriate.