Category: Prior Clinic Blog
JOURNAL: Br J Obstet Gynaecol 2002;109:1121-1125.
AUTHORS: Dr. Choy
ABSTRACT: High blood levels of mercury that might be caused by eating a lot of seafood are linked to infertility in men and women.
COMMENTARY: Dr. Christine Choy and others at the Chinese University of Hong Kong compared mercury levels in 157 infertile couples and 26 fertile couples. They found that 35% of the men and 23% of the women in the infertile group had abnormally high blood mercury concentrations, compared to 15% of men and 3.8% of women in the fertile group.
Among men, mean blood mercury levels were 44.2 mmol/L in those with abnormal semen compared with 31.2 mmol/L in the control group. Among women, levels were 37.0 mmol/L in those with unexplained infertility versus 17.5 mmol/L in the controls.
The researchers also recorded the levels of seafood consumed by the couples and found that patients who reported eating more seafood tended to have higher blood mercury levels.
Contamination of the marine waters around Hong Kong with heavy metals is common, they note. "Seafood contaminated with mercury is a possible source of excessive mercury exposure in our infertile population," Dr. Choy and colleagues write.
"The positive correlation between quantity of seafood consumption and blood mercury concentrations suggests that higher seafood consumption may contribute to higher blood mercury concentrations."
In men, mercury might disrupt sperm membrane permeability, mitochondrial function or microtubule-generated motion, the researchers note. How the metal might affect female fertility is less clear, although it could induce some cytotoxic or genotoxic damage in the ovaries, they suggest.
Dr. Choy said cutting back on seafood could be a way of avoiding high blood mercury levels. "However, this should be balanced against the beneficial effects of other components of fish, such as those of 3-omega fatty acids and selenium," she added.
STUDY: Preventing falls among older people is crucial
JOURNAL: British Medical Journal 2002;325:128-131
AUTHORS: Dr. Lesley Day
ABSTRACT: Healthy elderly people living on their own who exercised in a group weekly and on their own twice a week were less likely to fall, according to the results of an Australian study.
COMMENTARY: Preventing falls among older people is crucial for their health and ability to live independently, because falls often result in debilitating injuries such as hip fractures.
Dr. Lesley Day of Monash University in Victoria and colleagues randomly assigned 1,090 people aged 70 to 84 to an exercise program, home hazard management, vision improvement, or combinations of these interventions. The exercise component included a 1-hour weekly exercise class supplemented by daily home exercises. About one third of the exercises were designed to improve balance; flexibility and leg strength were also addressed.
At the end of 15 weeks, study participants who exercised showed improvements in thigh muscle strength, stability and balance. At the end of 18 months, the increase in muscle strength had disappeared, but improvements in balance remained.
Patients who exercised were 18% less likely to fall during the course of the study. While home hazard reduction or vision improvement alone did not prevent falls, study participants who completed all three interventions showed the most dramatic reduction in falls. Those who exercised and completed the home hazard and vision improvements were 33% less likely to fall during the study.
The investigators conclude that improved balance was behind the fall reduction among exercisers.
Compliance with home exercise was relatively poor, with participants working out an average of only twice weekly. This is the lowest intensity group-based exercise program shown to be effective in reducing falls among community-dwelling older people.
The Australian team estimated that 14 clients would need to receive the exercise intervention to prevent one fall annually. Only half that number would need to participate if all three components were included in the intervention.
Participation in an exercise intervention is appropriate for senior citizens living on their own, who are of relatively good health, and who have their family doctor's approval. She added that community agencies and local government organizations can deliver such interventions effectively.
STUDY: Veggie Diet no Better the Flesh Diet for Type 2 Diabetes
JOURNAL: Diabetes Care 2002;25:1277-1282,1474-1476.
AUTHORS: Dr. S. Edwin Fineberg
ABSTRACT: A diet that derives protein from plant sources only has no advantage over a diet that contains animal protein for individuals with type 2 diabetes and microalbuminuria.
COMMENTARY: In a randomized crossover trial, Dr. S. Edwin Fineberg and colleagues from Indiana University School of Medicine, Indianapolis, compared a diet containing only plant proteins with one containing mostly animal proteins in 17 patients with type 2 diabetes and microalbuminuria.
After the patients had been on each diet for 6 weeks, the researchers found that there was no diet-related difference in the glomerular filtration rate, renal plasma flow, albumin excretion rate, total cholesterol, HDL cholesterol, triglyceride area under the curve (AUC), glucose and insulin AUC, HbA1c, blood pressure, or serum amino acids.
Both diets were associated with lowered cholesterol, improved HbA1c, and reduced diastolic blood pressure, according to the report in the August issue of Diabetes Care. There was no difference in dietary effects on renal function, whether or not patients were treated with angiotensin converting enzyme inhibitors.
Dr. Fineberg and colleagues conclude that "there appears to be no clear advantage to recommending plant protein over animal protein to improve renal function or lipid and glycemic parameters in people who have type 2 diabetes and microalbuminuria."
STUDY: A dose-response relationship in which 7g of almonds lowered low-density (LDL) cholesterol levels by 1%.
JOURNAL: Circulation. 2002;106:000-000
AUTHORS: David J. A. Jenkins, MD
ABSTRACT: Although nuts have been touted to be beneficial for heart disease, some physicians have hesitated to recommend them due to their high fat content. In a calorie-controlled trial investigators demonstrated a dose-response relationship in which 7g of almonds lowered low-density (LDL) cholesterol levels by 1%.
COMMENTARY: This study suggests that replacing carbohydrates with monounsaturated fat — within the context of a diet that is low in saturated, trans fat and cholesterol — favorably affects cholesterol levels and cardiovascular risk.
This three-phase, randomized, crossover design study enrolled 27 patients with high cholesterol, including 15 men and 12 postmenopausal women. Average age was 64 years, and average baseline total cholesterol level was 260 mg/dL. The three test diets, which each subject followed for one month, included an isoenergetic supplement (mean, 423 kcal/day) comprising 22.2% of caloric intake. The full-dose almond supplement consisted of about 74 g of almonds daily; the half-dose almond supplement included about 37 g or a "handful" of almonds; and the control supplement was a low-saturated fat, whole-wheat muffin.
Full-dose almonds produced the greatest reduction in blood lipid levels, and the control diet produced no significant reductions. Compared with baseline, both half- and full-dose almonds reduced LDL cholesterol (4.4% ±1.7%, P=.018, and 9.4% ±1.9%, P<.001, respectively) and ratio of LDL to high-density lipoprotein (HDL) cholesterol (7.8% ±2.2%, P=.001, and 12.0% ±2.1%, P<.001). Full-dose almonds reduced lipoprotein(a) by 7.8% ±3.5% (P=.034) and oxidized LDL concentrations by 14.0% ±3.8% (P<.001). There was no difference in pulmonary nitric oxide between treatments.
If you look at the ratio of LDL to HDL, the reduction was 7.8% for the half dose and 12% for the full dose by the fourth week. That ratio is very important in assessing cardiovascular risk.
It is recommended that physicians encourage patients to eat almonds as part of a healthy balanced diet, provided they are natural or "dry roasted" without added oils or salts.
The dose-response to almonds appears linear in the acceptable range of intake, with a 1% reduction in LDL cholesterol resulting from each 7g portion of almonds.
Eat a small handfull a day. Try to substitute these for an unhealthier snack that you would have eaten.
JOURNAL: Association for Cancer R; 2004 Mar;13(3) p405 - 411
AUTHORS: Horn-Ross P; Canchola A; West D; Stewart S; Bernstein L; Deapen
ABSTRACT: Alcohol consumption of approximately two drinks or more per day has been
associated with elevated breast cancer risk in the California Teachers
Study cohort as well as in many other populations.
COMMENTARY: The objective of this analysis is to examine effects of age at drinking and drinking patterns and to identify effect modifiers.
Of the 103,460 at-risk cohort members, age <85, who resided in California and completed the baseline alcohol assessment, 1,742 were diagnosed with invasive breast cancer after joining the cohort and before January 2001.
Incident breast cancers were identified through the California Cancer Registry and follow-up for death and confirmation of continued California residence used various sources. Multivariate Coxproportional hazards regression models were used to estimate relative risks (RRs).
Elevated breast cancer risk was most evident for recent drinking [RR = 1.28, 95% confidence interval (CI): 1.06-1.54 for >/==" BORDER="0">20g/day versus nondrinkers], with with no clear pattern for consumption during
earlier periods of life.
This elevation in risk was 32% among postmenopausal women (95% CI: 1.06-1.63) and 21% among pre/perimenopausal women (95%CI: 0.76-1.92). Highest risks associated with heavy alcohol consumption were observed among postmenopausal women with a history of biopsy-diagnosed benign breast disease (RR = 1.97, 95% CI: 1.39-2.79 compared to nondrinkers without benign breast disease) or who had used combination hormone replacement therapy (HRT) (RR = 2.24, 95% CI: 1.59-3.14 compared to nondrinkers who never used HRT).
Recent alcohol consumption equivalent to two or more drinks per day increases the risk of invasive breast cancer, with the greatest RRs observed among heavy drinkers who are also postmenopausal and have a history of benign breast disease or who use HRT.