Archive for August, 2011

Organic farming reduces resistance of bacteria to antibiotics, study finds

Tuesday, August 30th, 2011
By Rob Stein

Poultry farmers who adopt organic practices and stop giving their birds antibiotics significantly reduce the resistance of bacteria to antibiotics in their flocks, according to a study released Wednesday.

Public health experts have become increasingly concerned about germs becoming resistant to many commonly used antibiotics. In fact, an outbreak of salmonella currently occurring is being caused by a resistant strain of the bacteria traced back to ground turkey.

In the new study, published in the journal Environmental Health Perspectives, Amy Sapkota of the University of Maryland School of Public Health and colleagues studied 10 conventional farms and 10 farms that had recently become organic in 2008. They tested for the presence of a bacteria known as enterococci in poultry litter, feed and water and for whether the organisms were resistant to 17 commonly used drugs.

All the farms tested positive for the bacteria. But the farms that had recently become organic had significantly lower levels of resistance. For example, 67 percent of enterococcus faecalis from conventional farms were resistant to the drug erythromycin compared to 18 percent of the organisms from the organic farms. Forty-two percent of the bacteria from conventional farms were resistant to multiple drugs, compared to only 10 percent from the organic farms.

“We initially hypothesized that we would see some differences in on-farm levels of antibiotic-resistant enterococci when poultry farms transitioned to organic practices,” Sapkota said. “But we were surprised to see that the differences were so significant across several different classes of antibiotics even in the very first flock that was produced after the transition to organic standards.”

Farm industry officials have long argued that antibiotics are extremely important to protecting the health of farm animals and keeping the food supply safe.

Decrease of Blood Pressure with Regular Consumption of Orange Juice

Tuesday, August 30th, 2011
Source: American Journal of Clinical Nutrition

Blood pressure is the amount of force required for the heart to circulate blood through the body. Systolic blood pressure represents the maximal blood pressure during systole, and diastolic blood pressure the minimum pressure at the end of ventricular diastole. Arterial blood pressure can be defined hemodynamically as the product of cardiac output and total peripheral resistance. Cardiac output is the main determinant of systolic pressure while peripheral resistance largely determines the level of diastolic pressure. Hypertension is a cardiovascular disease characterized by elevation of blood pressure above arbitrary values considered normal for people of similar racial and environmental background. Hypertension affects the vasculature of all major organs (heart, brain, kidneys), and myocardial infarction and congestive heart failure account for the majority of deaths secondary to hypertension.

A study published in the American Journal of Clinical Nutrition investigated the effect of orange juice and its major flavonoid, hesperidin, on blood pressure and cardiovascular risk biomarkers. The study included 24 healthy, moderately overweight men who were randomized to consume either 500 mL orange juice, or 500 mL hesperidin or 500 mL placebo drink for four weeks. The results revealed that diastolic blood pressure was significantly lowered after four weeks consumption of orange juice or a hesperidin drink when compared to the placebo drink. It was also determined that orange juice and hesperidin significantly improved post-meal blood vessel reactivity compared with placebo. These results appear to suggest hesperidin may contribute to the beneficial effects of orange juice, which may reduce diastolic blood pressure and increase post-meal blood vessel reactivity.1

1 Morand C, Dubray C, Milenkovic D, et al. Hesperidin contributes to the vascular protective effects of orange juice: a randomized crossover study in healthy volunteers. Am J Clin Nutr. 2010.