naturopathydigest.com -- Critical Research

buy microsoft office enterprise 2007

buy Microsoft Office 2003 Professional sp3buy autodesk autocad 2009

Critical Research

Critical Research is a regular feature in Naturopathy Digest. Each month, we provide abstracts from studies published in the top peer-reviewed journals; each abstract includes the complete citation and an online link to the journal. Whenever possible, this link directs you to a page where you can order the full text of the study, if desired.

This Month's Featured Abstract

Fruit and vegetable consumption among adults – United States, 2005.

Centers for Disease Control and Prevention

A diet high in fruits and vegetables is associated with decreased risk for chronic diseases. In addition, because fruits and vegetables have low energy density (i.e., few calories relative to volume), eating them as part of a reduced-calorie diet can be beneficial for weight management. Healthy People 2010 health objectives include increasing to 75% the percentage of persons aged >/=2 years who eat at least two daily servings of fruit (objective 19-5) and increasing to 50% the proportion of persons aged >/=2 years who eat at least three daily servings of vegetables, with at least one third being dark green or orange vegetables (objective 19-6). To assess the level of fruit and vegetable consumption among adults by state and demographic characteristics, data from the 2005 Behavioral Risk Factor Surveillance System (BRFSS) were analyzed. This report describes the results of that analysis, which indicated that 32.6% of adults consumed fruit two or more times per day and 27.2% ate vegetables three or more times per day. The results underscore the need for continued interventions that encourage greater fruit and vegetable consumption among U.S. adults.
Source: MMWR Morb Mortal Wkly Rep, March 16, 2007;56(10):213-7.

Effects of Panax ginseng, consumed with and without glucose, on blood glucose levels and cognitive performance during sustained “mentally demanding” tasks.

JL Reay, DO Kennedy, AB Scholey

Single doses of the traditional herbal treatment Panax ginseng have recently been shown to lower blood glucose levels and elicit cognitive improvements in healthy, overnight-fasted volunteers. The specific mechanisms responsible for these effects are not known. However, cognitive improvements may be related to the glycemic properties of Panax ginseng. Using a double-blind, placebo-controlled, balanced-crossover design, 27 healthy young adults completed a 10-minute “cognitive demand” test battery at baseline. They then consumed capsules containing either ginseng (extract G115) or a placebo, and 30 minutes later, a drink containing glucose or placebo. A further 30 minutes later (i.e., 60 minutes post-baseline/capsules) they completed the “cognitive demand” battery six times in immediate succession. Depending on the condition to which the participant was allocated on that particular day, the combination of capsules/drink treatments corresponded to a dose of: 0 mg G115/0 mg glucose (placebo); 200 mg G115/0 mg glucose (ginseng); 0 mg G115/25 g glucose (glucose) or 200 mg G115/25 g glucose (ginseng/glucose combination). The 10-minute “cognitive demand” battery comprised a Serial Threes subtraction task (2 min); a Serial Sevens subtraction task (2 min); a Rapid Visual Information Processing task (5 min); and a “mental fatigue” visual analogue scale. Blood glucose levels were measured prior to the day’s treatment, and before and after the post-dose completions of the battery. The results showed that both Panax ginseng and glucose enhanced performance of a mental arithmetic task and ameliorated the increase in subjective feelings of mental fatigue experienced by participants during the later stages of the sustained, cognitively demanding task performance. Accuracy of performing the Rapid Visual Information Processing task (RVIP) was also improved following the glucose load. There was no evidence of a synergistic relationship between Panax ginseng and exogenous glucose ingestion on any cognitive outcome measure. Panax ginseng caused a reduction in blood glucose levels 1 hour following consumption when ingested without glucose. These results confirm that Panax ginseng may possess glucoregulatory properties and can enhance cognitive performance.
Source: J Psychopharmacol, Nov 2006;20(6):771-81.

Clinical effects produced by a standardized herbal medicinal product of Hibiscus sabdariffa on patients with hypertension. A randomized, double-blind, lisinopril-controlled clinical trial.

A Herrera-Arellano, J Miranda-Sanchez, P Avila-Castro, et al.

Hibiscus sabdariffa L. (Malvaceae) has been used in different countries as an antihypertensive. Pharmacological work has demonstrated that this effect is probably produced by a diuretic activity and inhibition of the angiotensin-converting enzyme (ACE). Two clinical trials have confirmed the antihypertensive effect using watery infusions, in which a natriuretic effect was also detected. To compare therapeutic effectiveness, tolerability, and safety, as well as the effect on serum electrolytes and the ACE inhibitory effect of a herbal medicinal product prepared from the dried extract of H. sabdariffa calyxes (HsHMP) with those of lisinopril on patients with hypertension (HT), a randomized, controlled, and double-blind clinical trial was conducted. Patients of either sex, 25 - 61 years of age, with hypertension stage I or II, were daily treated for 4 weeks with the HsHMP, 250 mg of total anthocyanins per dose (experimental group), or 10 mg of lisinopril (control group). Outcome variables included effectiveness (diastolic blood pressure [DBP] reduction, > or = 10 mmHg), safety (absence of pathological modifications in the biochemical tests of hepatic and renal function), tolerability (absence of intense side effects), effect on serum electrolytes, and effect on ACE activity. Basal analysis included 193 subjects (100 in the experimental group), while outcome variable analysis integrated 171. Results showed that the experimental treatment decreased blood pressure (BP) from 146.48/97.77 to 129.89/85.96 mmHg, reaching an absolute reduction of 17.14/11.97 mmHg (11.58/12.21%, p < 0.05). The experimental treatment showed therapeutic effectiveness of 65.12% as well as tolerability and safety of 100%. BP reductions and therapeutic effectiveness were lower than those obtained with lisinopril (p < 0.05). Under the experimental treatment, the serum chlorine level increased from 91.71 to 95.13 mmol/L (p = 0.0001), the sodium level showed a tendency to decrease (from 139.09 to 137.35, p = 0.07), while potassium level was not modified. ACE plasmatic activity was inhibited by HsHMP from 44.049 to 30.1 Units (Us; p = 0.0001). In conclusion, the HsHMP exerted important antihypertensive effectiveness with a wide margin of tolerability and safety, while it also significantly reduced plasma ACE activity and demonstrated a tendency to reduce serum sodium (Na) concentrations without modifying potassium (K) levels. Further studies are necessary for evaluating the dose-dependency of HsHMP and for detecting lower effective doses.
Source: Planta Med, Jan 2007;73(1):6-12.

Prenatal multivitamin supplementation and rates of pediatric cancers: a meta-analysis.

YI Goh, E Bollano, TR Einarson, G Koren

Prenatal supplementation of folic acid has been shown to decrease the risk of several congenital malformations. Several studies have recently suggested a potential protective effect of folic acid on certain pediatric cancers. The protective role of prenatal multivitamins has not been elucidated. We conducted a systematic review and meta-analysis to assess the potential protective effect of prenatal multivitamins on several pediatric cancers. Medline, PubMed, EMBASE, Toxline, Healthstar, and Cochrane databases were searched for studies published in all languages from 1960 to July 2005 on multivitamin supplementation and pediatric cancers. References from all articles collected were reviewed for additional articles. Two blinded independent reviewers assessed the articles for inclusion and exclusion. Rates of cancers in women supplemented with multivitamins were compared with unsupplemented women using a random effects model. Sixty-one articles were identified in the initial search, of which, seven articles met the inclusion criteria. There was an apparent protective effect for leukemia (odds ratio (OR)=0.61, 95% confidence interval (CI)=0.50-0.74), pediatric brain tumors (OR=0.73, 95% CI=0.60-0.88) and neuroblastoma (OR=0.53, 95% CI=0.42-0.68). In conclusion, maternal ingestion of prenatal multivitamins is associated with a decreased risk for pediatric brain tumors, neuroblastoma, and leukemia. Presently, it is not known which constituent(s) among the multivitamins confer this protective effect.
Source: Clin Pharmacol Ther, Feb. 21, 2007 [Epub ahead of print].

The acute effects of exercise on cigarette cravings, withdrawal symptoms, affect and smoking behaviour: a systematic review.

AH Taylor, MH Ussher, G Faulkner

Aim: To review the effects of a single session of exercise on cigarette cravings, withdrawal symptoms and smoking behaviour.
Methods: A systematic search and critical appraisal of all 14 relevant studies.
Results: All 12 studies that compared a bout of exercise with a passive condition reported a positive effect on cigarette cravings, withdrawal symptoms and smoking behaviour. Two other studies that compared two intensities of exercise revealed no differences in outcomes. Single and multi-item measures of cigarette cravings, withdrawal symptoms and negative affect decreased rapidly during exercise and remained reduced for up to 50 minutes after exercise. Effect sizes for seven studies that assessed strength of desire to smoke showed a mean reduction, 10 minutes after exercise, of 1.1 (SD 0.9). Four studies reported a two- to threefold longer time to the next cigarette following exercise. Cravings and withdrawal symptoms were reduced with an exercise intensity from as high as 60-85% heart rate reserve (HRR) (lasting 30-40 minutes) to as low as 24% HRR (lasting 15 minutes), and also with isometric exercise (for 5 minutes). All but one study involved participants temporarily abstaining for the purposes of the experiment. Distraction was probably not the primary reason for the effects.
Conclusions: Relatively small doses of exercise should be recommended as an aid to managing cigarette cravings and withdrawal symptoms. Further research to understand the mechanisms involved, such as stress reduction or neurobiological mechanisms, could lead to development of more effective and practical methods to reduce withdrawal phenomena.
Source: Addiction, April 2007;102(4):534-543.

Normal-weight obese syndrome: early inflammation?

A De Lorenzo, V Del Gobbo, MG Premrov, M Bigioni, F Galvano, L Di Renzo

Background: In obese subjects, the adipose mass represents an important source of pro-inflammatory cytokines. We have identified a new syndrome–the normal-weight obese (NWO) syndrome-in women with normal weight and body mass index but whose fat mass is >30% of their total body weight and whose risk of developing obesity-related diseases is likely increased.
Objective: The aim of the present study was to verify the hypothesis that NWO women are characterized by early inflammation, related to body fat mass, and that their plasma pro-inflammatory cytokine concentrations are greater than those of nonobese women.
Design: Twenty NWO, 20 pre-obese-obese, and 20 healthy (nonobese), age-matched white Italian women were studied. Anthropometric variables and plasma concentrations of pro-inflammatory cytokines and cardiovascular disease (CVD) risk factors were measured and compared between groups.
Results: Plasma values and body-composition measures were significantly different between the pre-obese-obese and nonobese women. No significant differences in body weight, laboratory values, or CVD risk factors were found between the NWO and nonobese groups. Compared with concentrations in the NWO women, plasma concentrations of interleukin (IL)-1alpha, IL-1beta, IL-6, IL-8, and TNF-alpha were significantly lower in the nonobese group and were significantly greater in the pre-obese-obese group. IL-6 and TNF-alpha concentrations were related to fat mass distribution in the NWO women.
Conclusions: The pro-inflammatory cytokines could be regarded as significant prognostic indicators of the risk of obesity, CVD, and the metabolic syndrome in NWO women.
Source: Am J Clin Nutr, Jan 2007;85(1):40-5.

Effect of calorie restriction with or without exercise on body composition and fat distribution.

LM Redman, LK Heilbronn, CK Martin, et al.

Context: There is debate over the independent and combined effects of dieting and increased physical activity on improving metabolic risk factors (body composition and fat distribution).
Objective: The objective of the study was to conduct a randomized, controlled trial (CALERIE) to test the effect of a 25% energy deficit by diet alone or diet plus exercise for 6 months on body composition and fat distribution.
Design: This was a randomized, controlled trial. Setting: The study was conducted at an institutional research center. Participants: Thirty-five of 36 overweight but otherwise healthy participants (16 males, 19 females) completed the study. Intervention: Participants were randomized to either control (healthy weight maintenance diet, n = 11), caloric restriction (CR; 25% reduction in energy intake, n = 12), or caloric restriction plus exercise (CR+EX; 12.5% reduction in energy intake + 12.5% increase in exercise energy expenditure, n = 12) for 6 months.
Main Outcome Measures: Changes in body composition by dual-energy X-ray absorptiometry and changes in abdominal fat distribution by multislice computed tomography were measured.
Results: The calculated energy deficit across the intervention was not different between CR and CR+EX. Participants lost approximately 10% of body weight (CR: - 8.3 +/- 0.8, CR+EX: - 8.1 +/- 0.8 kg, P = 1.00), approximately 24% of fat mass (CR: - 5.8 +/- 0.6, CR+EX: - 6.4 +/- 0.6 kg, P = 0.99), and 27% of abdominal visceral fat (CR: 0.9 +/- 0.2, CR+EX: 0.8 +/- 0.2 kg, P = 1.00). Both whole-body and abdominal fat distribution were not altered by the intervention.
Conclusion: Exercise plays an equivalent role to CR in terms of energy balance; however, it can also improve aerobic fitness, which has other important cardiovascular and metabolic implications.
Source: J Clin Endocrinol Metab, March 2007;92(3):865-72.

A randomized controlled trial of tai chi for tension headaches.

RB Abbott, KK Hui, RD Hays, et al.

This study examined whether a traditional low-impact mind-body exercise, tai chi, affects health-related quality-of-life (HRQOL) and headache impact in an adult population suffering from tension-type headaches. Forty-seven participants were randomly assigned to either a 15-week intervention program of tai chi instruction or a wait-list control group. HRQOL (SF-36v2) and headache status (HIT-6™) were obtained at baseline and at 5, 10 and 15 weeks post-baseline during the intervention period. Statistically significant (P < 0.05) improvements in favor of the intervention were present for the HIT score and the SF-36 pain, energy/fatigue, social functioning, emotional well-being and mental health summary scores. A 15-week intervention of tai chi practice was effective in reducing headache impact and also effective in improving perceptions of some aspects of physical and mental health.
Source: Evid Based Complement Alternat Med, March 2007;4(1):107-13.