Dr. John's Health Matters
Welcome to Dr. John's Health Matters blog.
The articles posted here are from various sources who are duly acknowledged. I would appreciate being immediately notified, if any copywritten material needs to be removed. This blog is not intended to replace the qualified advice of a licensed health practitioner. Readers should exercise their own judgment. Enjoy, subscribe, participate and tell others :)
Following:
Navigate
COMING SOON!
Expand all | Collapse all 
Search
Click Tags under Articles
NOTE: SEARCH BY KEYWORD FUNCTIONS BELOW ARE TEMPORARILY MALFUNCTIONING. USE AT OWN RISK.
Or Display Full Article by
Posts tagged "risk"
Wednesday, Sep 2nd, 2009 ↓To spray DEET or not to spray? →
Sept 2, 2009 (Cbc.ca)—DEET, the most common chemical ingredient in insect repellents, could be harmful to the central nervous system, new research suggests.
A report on the subject issued by researchers in France, in both Montpellier and Angers, was published on Aug. 5.
“We’ve found that DEET is not simply a behaviour-modifying chemical but also inhibits the activity of a key central nervous system enzyme, acetycholinesterase, in both insects and mammals,” said Vincent Corbeil, of the Institut de Recherche pour le Développement in Montpellier.
DEET — also known by its full name N, N-diethyl-methyl-meta-toluamide — has proven effective since its discovery in 1953 at warding off insects, including mosquitoes.
Used with insecticides
It does not kill bugs, but its vapours discourage them from landing or climbing on people. As well, the higher the DEET concentration in a repellent formula, the longer it provides protection. DEET is commonly used with insecticides, also.
About 200 million people use DEET every year, and it’s estimated that more than eight billion doses have been applied over the past 50 years, according to the journal BMC Biology.
“The findings question the safety of DEET, particularly in combination with other chemicals, and they highlight the importance of a multidisciplinary approach to the development of safer insect repellents for use in public health,” the French researchers wrote.
For full article, see link above.
Tags: DEET risk bug spray protection chemical toxin repellent acetycholinesterase nervous system
Diesel Exhaust Is Linked To Cancer Development Via New Blood Vessel Growth →
Sept 2, 2009 (Sciencedaily.com)—Scientists have demonstrated that the link between diesel fume exposure and cancer lies in the ability of diesel exhaust to induce the growth of new blood vessels that serve as a food supply for solid tumors.
The researchers found that in both healthy and diseased animals, more new blood vessels sprouted in mice exposed to diesel exhaust than did in mice exposed to clean, filtered air. This suggests that previous illness isn’t required to make humans susceptible to the damaging effects of the diesel exhaust.
The tiny size of inhaled diesel particles, most less than 0.1 microns in diameter, potentially enables them to penetrate the human circulatory system, organs and tissues, meaning they can do this damage just about anywhere in the body. A micron is one millionth of a meter.
Diesel exhaust exposure levels in the study were designed to mimic the exposure people might experience while living in urban areas and commuting in heavy traffic. The levels were lower than or similar to those typically experienced by workers who use diesel-powered equipment, who tend to work in mines, on bridges and tunnels, along railroads, at loading docks, on farms and in vehicle maintenance garages, according to the U.S. Department of Labor.
“The message from our study is that exposure to diesel exhaust for just a short time period of two months could give even normal tissue the potential to develop a tumor,” said Qinghua Sun, senior author of the study and an assistant professor of environmental health sciences at Ohio State University.
“We need to raise public awareness so people give more thought to how they drive and how they live so they can pursue ways to protect themselves and improve their health. And we still have a lot of work to do to improve diesel engines so they generate fewer particles and exhaust that can be released into the ambient air.”
For full article, see link above.
Tags: disesel exhaust air damage risk cancer blood vessel tumor organ tissues circulatory system traffic environmental pollution
Waist-hip Ratio Better Than BMI For Gauging Obesity In Elderly, Study Finds →
Sept 2, 2009 (Sciencedaily.com)—Body mass index (BMI) readings may not be the best gauge of obesity in older adults, according to new research from UCLA endocrinologists and geriatricians. Instead, they say, the ratio of waist size to hip size may be a better indicator when it comes to those over 70.
In a new study published online in the peer-reviewed journal Annals of Epidemiology, researchers from the David Geffen School of Medicine at UCLA found that the waist-to-hip circumference ratio was a better yardstick for assessing obesity in high-functioning adults between the ages of 70 and 80, presumably because the physical changes that are part of the aging process alter the body proportions on which BMI is based.
“Basically, it isn’t BMI that matters in older adults — it’s waist size,” said Dr. Preethi Srikanthan, UCLA assistant professor of endocrinology and the study’s lead investigator. “Other studies have suggested that both waist size and BMI matter in young and middle-aged adults and that BMI may not be useful in older adults; this is one of the first studies to show that relative waist size does matter in older adults, even if BMI does not matter.”
For full article, see link above.
Weight Gain In Adulthood Associated With Prostate Cancer Risk; Patterns Differ By Ethnicity →
Sept 2, 2009 (Sciencedaily.com)—Body mass in younger and older adulthood, and weight gain between these periods of life, may influence a man’s risk for prostate cancer. This risk varies among different ethnic populations, according to results of a study in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
“The relationship of certain characteristics, such as body size, with cancer risk may vary across ethnic groups due to the combined influence of both genes and lifestyle,” said lead researcher Brenda Y. Hernandez, Ph.D., M.P.H., assistant professor at the Cancer Research Center of Hawaii, University of Hawaii.
Obesity is a risk factor for common cancers like colorectal cancer and breast cancer in post-menopausal women. However, the influence of body size on prostate cancer risk is not entirely understood. Hernandez and colleagues examined this relationship in a multiethnic population consisting of blacks, Japanese, Hispanics, Native Hawaiians and whites, and compared differences among age groups. They used the Multiethnic Cohort, a longitudinal study of men aged 45 to 75 years old established in Hawaii and California from 1993 to 1996.
For full article, see link above.
Tags: weight gain prostate cancer risk BMI body size ethnic group genes lifestyle obesity factor
People Who Don't Own A Car And Live Near Fast Food At Greater Risk For Obesity →
Sept 2, 2009 (Sciencedaily.com)—Living without a car in close proximity to fast food restaurants is associated with excess body mass index and weight gain, according to a University of Pittsburgh study available online and published in the September issue of the Journal of Urban Health. Indeed, adults in areas with high fast food concentration who didn’t have a car were as much as 12 pounds heavier than those who lived in neighborhoods that lacked such restaurants.
“Owning a car is generally associated with a more sedentary lifestyle and excess weight gain because people spend more time in their cars and less time walking,” said Sanae Inagami, M.D., study lead author and assistant professor, University of Pittsburgh School of Medicine. Yet, when Inagami and her colleagues looked at whether a high concentration of fast food restaurants impacted this association, they found that not owning a car in areas where fast food was more readily available increased the risk of obesity.
“Fast food may be specific to weight gain in particular populations and locations,” she said. “People who are less affluent don’t own cars and can’t go distances for healthier foods. As a result, they may end up opting for the lower-priced and high caloric foods available at fast food chains.”
For full article see link above.
Tags: car driving food fast fat obesity restaurant lifestyle sedentary weight gain walking risk overweight neighbourhood
Breast Cancer: Risk Increases For Smokers And Overweight Women →
Sept 1, 2009 (Sciencedaily.com)—A recent study published in the Journal of Cancer Epidemiology has reinforced the correlation between being overweight, smoking and breast cancer. What makes this study unique is how test subjects were not diagnosed for BRCA1 and BRCA2 gene mutations, which predispose women to breast cancer.
Instead, women with such gene mutations were excluded to allow researchers to concentrate on lifestyle factors such as smoking, exercise, nutrition and weight. All women analyzed in the study were direct ancestors of the first French colonists.
“To our knowledge, this is the first study conducted on a sample of women without BRCA1 and BRCA2 gene mutations, which are often found in French-Canadian women,” says lead researcher Vishnee Bissonauth, a graduate of the Université de Montréal’s Department of Nutrition and a researcher at the Sainte-Justine University Hospital Research Center.
For full article, see link above.
Tags: smoking breast cancer risk overweight obesity cigarette smoker gene mutation correlation
Tobacco Smoking May Increase Risk for Tuberculosis →
September 1, 2009 (Medscape.com)— Tobacco smoking is associated with a 2-fold increased risk for active tuberculosis, according to the results of a prospective Taiwan cohort study reported in the September 1 issue of the American Journal of Respiratory and Critical Care Medicine.
“Previous case-control studies and a small number of cohort studies in high-risk populations have found an association between tobacco and active tuberculosis, but no cohort studies have been conducted in the general population on this association to date,” write Hsien-Ho Lin, MD, ScD, from Harvard School of Public Health in Boston, Massachusetts, and colleagues.
The goal of the study was to evaluate the association between tobacco smoking and active tuberculosis in a general population cohort of 17,699 participants older than 12 years enrolled in the Taiwan National Health Interview Survey. An in-person interview at baseline determined smoking status and other covariates. During follow-up from 2001 to 2004, incident cases of active tuberculosis were identified with use of the National Health Insurance database. After adjustment for age, sex, alcohol intake, socioeconomic status, and other covariates, the association between smoking status and active tuberculosis was estimated with multivariate logistic regression.
During the 3.3 years of follow-up, there were 57 new cases of active tuberculosis. Current smoking was linked to an increased risk for active tuberculosis (adjusted odds ratio [OR], 1.94; 95% confidence interval, 1.01 - 3.73). Compared with patients older than 65 years, those younger than 65 years showed a stronger association between current smoking and the risk for active tuberculosis (adjusted OR, 3.04 vs 0.78; P for interaction = .036). There were significant dose-response associations for cigarettes per day (P for trend = .0036), years of smoking (P for trend = 0.023), and pack-years (P for trend = .0023).
“Tobacco smoking was associated with a twofold increased risk of active tuberculosis in a representative cohort of Taiwan’s population,” the study authors write. “The finding that smoking increases the risk of tuberculosis suggests that tobacco control be considered as an important component in the global effort to eliminate tuberculosis.”
For full medical article, see link above.
Caution on mix of cholesterol-lowering meds →
Sept 1, 2009 (Cbc.ca)—Combining a prescription cholesterol-lowering medication with omega-3 supplements may not be the best approach, a new review suggests.
Statins are medications that prevent the liver from producing cholesterol, which can help reduce the risk of heart attacks. Every year, Canadian doctors write more than 12 million prescriptions for statins, making them the most-prescribed drugs in the country. Omega-3’s are heart-healthy oils that some evidence suggests help reduce the risk of coronary disease.
In the Nov. 3 issue of the Annals of Internal Medicine, Dr. Mukul Sharma, medical director of the Regional Stroke Centre at the Ottawa Hospital, and his team reviewed five different cholesterol-lowering medications that can be combined as well as omega-3 supplements sold over the counter. They concluded there is little evidence to support mixing them.
Bad cholesterol increase
In one case, the researchers found taking prescription medication with omega-3 had the opposite effect.
“Your bad cholesterol, the LDL, actually goes up,” Sharma said. “There isn’t a benefit in terms of heart disease, stroke or mortality.”
Most cholesterol patients may be better off taking higher doses of one drug instead of multiple medications, since there may be less chance of side-effects and long-term problems developing, he said. People are also less likely to take their medications the more that are prescribed.
For full article, see link above.
Tags: cholesterol increase risk danger LDL prescription cardiovascular blood heart statin medication liver heart attack prevention coronary disease
Heart Suffers From Just a Few Whiffs of Smoke →
Sept 1, 2009 (Therapytimes.com)—Just a few whiffs of tobacco smoke or dirty air can have a profound negative impact on your heart’s health.
Study results released today by the American Heart Association suggest that exposure to even a small amount of smoke — whether it’s from your own cigarette or someone else’s — greatly increases your risk of dying from cardiovascular disease. The same goes for breathing in air polluted with carbon monoxide emissions.
“It doesn’t require extreme exposure to have significant cardiovascular effects. Even passive exposures to ambient air pollution and secondhand smoke contribute to significant increases in cardiovascular mortality,” study author C. Arden Pope III, PhD, says in a statement.
For full article, see link above.
Tags: heart cardiovascular risk disease smoke tobacco risk danger exposure cigarette breathing air pollution
How Cigarettes and Smoking Impact Your Pet’s Health →
Sept 1, 2009 (Mercola.com)—A growing body of research shows there are no safe levels of exposure to secondhand smoke — for humans or for animals. And one new study shows that nearly 30 percent of pet owners live with at least one smoker — a number far too high given the consequences of exposure to secondhand smoke (“SHS”)
An estimated 50,000 Americans lose their lives to secondhand smoke annually and 4 million youth (16 percent) are exposed to secondhand smoke in their homes. A number of studies have indicated that animals, too, face health risks when exposed to the toxins in secondhand smoke, from respiratory problems, allergies and even nasal and lung cancer in dogs and lymphoma in cats. In addition, the ASPCA, one of the largest animal rights groups in the U.S., lists tobacco smoke as a toxin that is dangerous to pets.
“Nicotine from secondhand smoke can have effects to the nervous systems of cats and dogs,” said Dr. Sharon Gwaltney-Brant, Medical Director of the ASPCA’s Animal Poison Control Center. “Environmental tobacco smoke has been shown to contain numerous cancer-causing compounds, making it hazardous for animals as well as humans.
In order to better protect dogs, cats or other pets, the foundation and ASPCA recommend that smokers—who often consider their domestic pets a part of the family—“take it outside” when they are smoking.
For full article, see link above.
Tags: cigarette second hand smoke smoking pet risk tobacco exposure nicotine nervous system cancer toxin
Parents Play Key Role In Whether Teen Tobacco Use Becomes A Daily Habit →
Sept 1, 2009 (Sciencedaily.com)—Researchers have found new evidence showing that parents play a key role in whether or not their adolescent children who experiment with tobacco progress to become daily smokers before they graduate from high school.
A study published on-line and in the September issue of journal Pediatrics shows that parents can be a positive or negative influence on their children’s future smoking habit.
“If parents really don’t want their children to smoke they need to communicate that by establishing clear guidelines in their families about not smoking and discuss them with their school-age children.” said Min Jung Kim, a research scientist with the University of Washington’s Social Development Research Group and lead author of the study.
At the same time, parents can increase their children’s chances of smoking by their own use of tobacco.
“If parents smoke, teens have more access to cigarettes than teens who have non-smoking parents. A second preventive measure for smoking parents is to quit smoking themselves,” said Kim.
For full article, see link above.
Tags: workplace job work stress bullying bully sleep disturbance disorder suicide prevention risk violence harassment behaviour hostile
Daylight-saving Time Leads To Less Sleep, More Injuries On The Job, Study Finds →
Sept 1, 2009 (Sciencedaily.com)—Every March, most Americans welcome the switch to daylight saving time because of the longer days, but also dread losing an hour of sleep after they move their clocks forward. Now a new study shows that losing just an hour of sleep could pose some dangerous consequences for those in hazardous work environments.
The findings are reported in the September issue of the Journal of Applied Psychology, which is published by the American Psychological Association.
“One hour of lost sleep may not seem like a lot. But our findings suggest it could have an impact on people’s ability to stay alert on the job and prevent serious injuries.” said the article’s lead author, Christopher Barnes, PhD. Barnes and co-author David Wagner, PhD, were both doctoral students in organizational behavior at Michigan State University when they conducted this research.
For full article, see link above.
Tags: daylight savings sun sleep day danger hazard work environment injury alert risk
Antioxidants Not Associated With Increased Melanoma Risk →
Sept 1. 2009 (Sciencedaily.com)—Antioxidant supplements do not appear to be associated with an increased risk of melanoma, according to a new report.
A recent randomized trial of antioxidants for cancer prevention found that daily supplementation with nutritionally appropriate doses of vitamins C and E, beta carotene, selenium and zinc appeared to increase the risk of melanoma in women four-fold, according to background information in the article. Because an estimated 48 percent to 55 percent of U.S. adults use vitamin or mineral supplements regularly, the potential harmful effects of these nutrients is alarming, the authors note.
Maryam M. Asgari, M.D., M.P.H., of Kaiser Permanente Northern California, Oakland, and colleagues examined the association between antioxidants and melanoma among 69,671 women and men who were participating in the Vitamins and Lifestyle (VITAL) study, designed to examine supplement use and cancer risk. At the beginning of the study, between 2000 and 2002, participants completed a 24-page questionnaire about lifestyle factors, health history, diet, supplement use and other cancer risk factors.
Intake of multivitamins and supplements during the previous 10 years, including selenium and beta carotene, was not associated with melanoma risk in either women or men. The researchers also examined the risk of melanoma associated with long-term use of supplemental beta carotene and selenium at doses comparable to the previous study and found no association.
“Consistent with the present results, case-control studies examining serologic [blood] levels of beta carotene, vitamin E and selenium did not find any association with subsequent risk of melanoma,” the authors write. “Moreover, the Nurses’ Health Study reported no association between intake of vitamins A, C and E and melanoma risk in 162,000 women during more than 1.6 million person-years of follow-up.”
For full article, see link above.
Tags: antioxidant supplement vitamin mineral C e beta carotene selenium zinc cancer risk nutrient melanoma lifestyle multivitamin
Secondhand Smoke Worsens Outcome of Acute Coronary Syndrome →
Aug 28, 2009 (Medscape.com)— - Environmental exposure to tobacco smoke - a known risk factor for myocardial infarction and other acute coronary syndromes (ACS) - can also worsen prognosis after ACS, according to a new study.
“These findings suggest that, by reducing exposure to secondhand smoke, smoke-free legislation may not only reduce the incidence of cardiovascular events, but may also improve prognosis in those who suffer them,” Professors Jill P. Pell and Sally Haw write in a featured editorial published with the study in the September issue of Heart.
For full medical article, see link above.
