Kim’s public health blog

The September 2009 issue of The American Journal of Clinical Nutrition reports the results of 3 human studies designed to better delineate the relation between animal foods and breast cancer risk. “These studies highlight two very important points,” said American Society for Nutrition Spokesperson Shelley McGuire, PhD. “First we all need to remember that there are really no such things as ‘bad’ foods. Second, observational studies that show associations between diet and health need to be considered with a proverbial grain of salt. These studies clearly provide additional and strong evidence that consumption of meat and dairy products by women does not, by itself, increase breast cancer risk. Further, moderate and mindful consumption of these foods can be very important in attaining optimal nutrition for most women who often do not consume sufficient iron and calcium.”

Harvard scientists, alongside researchers at Massachusetts General Hospital and the Dana-Farber Cancer Institute, “analyzed data from two large ongoing studies, the Nurses’ Health Study and the Health Professionals Follow-up Study.” In total, they looked at data on “nearly 1,300 people with colorectal cancer who’d been followed for an average of 12 years. All the patients in the study had surgery for colon cancer and many also had chemotherapy.” The editor-in-chief of the Journal of Clinical Oncology, Daniel G. Haller, MD, of the University of Pennsylvania Cancer Center, says that “they (the data) are not persuasive because, as observational studies, they do not rise to the level needed to change guidelines,” Comment: This will lead to the newest fad in use of aspirin which has many side effects, including spontaneous bleeding.

An editorial in this week’s Lancet lets the air out of the organic food movement. There is little evidence that the nutritional value of ‘organic’ products is better than food raised by other means,  but If one wants to buy organic food, do so because it might be fresher and taste better, contain less chemical residues, and is kinder to farmed animals. You have to decide if the price is worth the meal.

The decision to stop the standard treatment of flu patients with Tamiflu was due to its side effects, according to Professor Jaap van Dissel of the Leiden University Medical Centre. Giving Tamiflu to 200 otherwise healthy flu patients will only protect 1 patient from complications, but meanwhile 20 to 30 people will experience serious side effects. Comment: This looks like a science based decision rather than the political one made in the U.S.A. Also the Europeans are not so easily stampeded into mass action.

Scientists in Singapore, the Netherlands and France report that they have developed a novel immunization method that will induce fast and effective protection in humans against the life-threatening malaria parasite, Plasmodium falciparum, which infects 350 to 500 million people world-wide and kills over one million people each year. [Protection against a Malaria Challenge by Sporozoite Inoculation. The New England Journal of Medicine, 361;5, July 30, 2009] Comment. While I hope this vaccine proves better than previous ones we must also wonder how the countries that use the vaccine will deal with the famine that may result from the increased population.

For the first time, scientists have shown that chimpanzees in the wild become sick and die from the simian version of AIDS. The finding upsets a widely held scientific belief that chimpanzees, the closest relatives to humans, can get the virus that causes simian AIDS but without harm. The study was published July 23, 2009, in the journal Nature. Virologist Beatrice Hahn of the University of Minnesota led the study, in collaboration with researchers from the University of Minnesota and other institutions.

Just to confuse us once more about nutrition, “drinking milk can lessen the chances of dying from illnesses such as heart disease and stroke by as much as 20 percent.” While “cow’s milk provides calcium, potassium, protein, and vitamin D,” it also contains “sugars and saturated fat,” so it “is often portrayed as an unhealthy choice.” For their paper, researchers at the UK’s Cardiff University and University of Reading conducted an analysis of “324 studies of milk consumption as predictors of coronary heart disease, stroke and diabetes.” They found that the “health benefits associated with the drink outweigh dangers.”

Mathematical modeling can help inform public health policy in outbreaks such as the H1N1 pandemic, write members of the Pandemic Influenza Outbreak Research Modeling Team in Canada. Mathematical models have shown that small seasonal variations in transmission of the influenza virus can drive large annual surges in the disease.

In a study to explore the link between early education programs and adult health, and how early educational interventions affect health outcomes, researchers at Columbia University Mailman School of Public Health found that early education reduces health behavioral risk factors by enhancing educational attainment, health insurance coverage, income, and family environments. Comment. This study shows one of the problems of long term cohort studies. There were only 123 individuals studied so that over 40 years there have been so many intervening variables that the cohort was not large enough from which to draw conclusions. It is very difficult to develop long term behavioral studies because so much of life intervenes and one cannot keep the exposures of the test group different from the random exposures of the comparison group. There can be no assurance that the early education exposure trumped the long term school exposures.

A new article “American Healthy Homes Survey: A National Study of Residential Pesticides Measured from Floor Wipes.” Environmental Science & Technology, 2009; 43 (12): 4294 tell us that technology can ,measure past use/abuse of pesticides in homes. Comment: However being able to measure a compound at parts per billion or less tell us nothing about possible causes/effects. It become one more tool for the EPA to use to get more funds because of potential peril.