A recent animal study has allegedly identified a new immunological connection between obesity and asthma involving “inflammasome activation and production of cytokine interleukin-17 by innate lymphoid cells in the lung,” according to a concurrent editorial published in Nature Medicine. Hye Young Kim, et al., “Interleukin-17-producing innate lymphoid cells and the NLRP3 inflammasome facilitate obesity-associated airway hyperreactivity,” Nature Medicine, January 2014. After studying mice that were raised on a high-fat diet until they became obese and developed asthma, researchers with Boston Children’s Hospital apparently reported that “obesity appeared to alter the innate immune system—the body’s first responder to infection—in several ways to cause lung inflammation.” In particular, they noted that, compared with non-obese mice, “the lungs of the obese, asthmatic mice had several differences”: (i) “High levels of the protein interleukin 17A (IL17A), a cytokine (signaling molecule) associated with several inflammatory conditions”; (ii) “Increased numbers of the immune cells that produce…
Category Archives Scientific/Technical Items
A recent systematic review of the current scientific literature “assigning obesity to the spectrum of neuropsychological diseases” has proposed “an integrative model” for understanding obesity not simply as a “deliberately flawed food intake behavior with the consequence of dysbalanced energetic uptake and expenditure,” but as a complex condition “linked to neurobio- logical and psychological aspects such as mood status, addictive behavior, motivation and reward processing as well as coping with psychosocial stress.” Kamila Jauch-Chara and Kerstin Oltmanns, “Obesity – A neuropsychological disease? Systematic review and neuropsychological model,” Progress in Neurobiology, January 2014. To this end, the reviewers highlight obesity research concluding, among other things, that (i) “chronic stress enhances food intake,” with both humans and animals choosing energy dense foods “to blunt their stress responses”; (ii) “food intake activates the reward circuitry” in the brain, increasing dopamine concentrations that correlate “positively with the rating of food pleasantness in humans”; and…
After analyzing reporting biases for 17 systematic reviews (SRs) assessing the association between sugar-sweetened beverages (SSBs) and weight gain, EU researchers have allegedly concluded that financial conflicts of interest may influence the outcomes of such studies. Maira Bes-Rastrollo, et al., “Financial Conflicts of Interest and Reporting Bias Regarding the Association between Sugar-Sweetened Beverages and Weight Gain: A Systematic Review of Systematic Reviews,” PLoS Medicine, December 2013. Selected from PubMed, Cochrane Library and Scopus databases, the SRs under scrutiny were classified as either finding a positive association between SSB consumption and weight gain or finding no association at all. “Among those reviews without any reported conflict of interest, 83.3% of the conclusions (10/12) were that SSB consumption could be a potential risk factor for weight gain,” report the study’s authors. “In contrast, the same percentage of conclusions, 83.3% (5/6), of those SRs disclosing some financial conflict of interest with the food…
York University researchers have published a qualitative study examining “how obese women with and without binge eating disorder (BED) experience overeating in relation to the DSM-5 [Diagnostic and Statistical Manual] symptoms of addiction.” Claire Curtis & Caroline Davis, “A Qualitative Study of Binge Eating and Obesity From an Addiction Perspective,” Eating Disorders, January 2014. According to the study, the recently-published DSM-5 includes a new category for “Addiction and Related Disorders” that addresses “both substance use disorders (SUDs) and non-substance addictions” in addition to providing new diagnostic guidelines. Using these expanded criteria, the authors interviewed 12 obese women with BED and 12 without BED, concluding that “both groups of women endorsed DSM-5 SUD criteria (in relation to food) in their narratives,” although there were “visible qualitative differences in how the women experienced these symptoms.” More specifically, Curtis and Davis reported that while both groups expressed a desire to reduce their food…
A recent study has reportedly revealed that organic milk contains a healthier balance of omega-6 and omega-3 fatty acids compared with milk from cows raised on conventionally managed dairy farms. Benbrook, et al., “Organic Production Enhances Milk Nutritional Quality by Shifting Fatty Acid Composition: A United States–Wide, 18-Month Study,” PLOS One, December 9, 2013. The finding, writes New York Times writer Kenneth Chang, is the “most clear-cut instance of an organic food’s offering a nutritional advantage over its conventional counterpart,” as “studies looking at organic fruits and vegetables have been less conclusive.” According to the researchers, who note that the ratio of omega-6 to omega-3 fatty acids in the U.S. diet have risen to “nutritionally undesirable levels,” the healthier fatty acid profile of organic milk is likely a result of cows foraging on grass. By comparison, cows fed a corn-based diet apparently produce milk that contains higher levels of omega-6 fatty acids, which…
The journal Food and Chemical Toxicology has announced the retraction of a controversial study purportedly linking genetically modified organisms (GMOs) to mammary tumors in rats. Led by University of Caen Molecular Biology Professor Gilles-Éric Séralin, the November 2012 study garnered public attention for reporting that female rats fed GM maize developed more mammary tumors than a control group raised on conventional feed. After further review, however, the journal’s editor-in-chief concluded that “both the low number of animals in each study group and the particular strain selected” were cause for concern. “A more in-depth look at the raw data revealed that no definitive conclusions can be reached with this small sample size regarding the role of either NK603 or glyphosate in regards to overall mortality or tumor incidence,” notes the journal’s retraction statement. “Given the known high incidence of tumors in the Sprague-Dawley rat, normal variability cannot be excluded as the…
An ongoing study presented at the Radiological Society of North America’s (RSNA’s) 99th Annual Scientific Assembly and Annual Meeting has reportedly claimed that energy drinks “significantly increased” heart contraction rates in healthy adults one hour after consumption. According to a December 2, 2013, RSNA press release, researchers with the University of Bonn, Germany, used cardiac magnetic resonance imaging (MRI) “to measure the effect of energy drink consumption in 18 healthy volunteers,” who apparently underwent cardiac MRI before and after consuming an energy drink containing 400 mg of taurine and 32 mg of caffeine. The results evidently showed that, compared to the baseline images, the MRI taken one hour after energy drink consumption “revealed significantly increased peak strain and peak systolic strain rates (measurements for contractility) in the left ventricle of the heart.” “Until now, we haven’t known exactly what effect these energy drinks have on the function of the heart,”…
A recent study funded by the National Cancer Institute has allegedly linked higher intakes of sugar-sweetened beverages (SSBs) to an increased risk of type I endometrial cancer. Maki Inoue-Choi, et al., “Sugar-Sweetened Beverage Intake and the Risk of Type I and Type II Endometrial Cancer among Postmenopausal Women,” Cancer, Epidemiology, Biomarkers & Prevention, December 2013. After evaluating the dietary intake of 23,039 postmenopausal women enrolled in the Iowa Women’s Health Study, University of Minnesota researchers apparently found that compared with women who did not consume SSBs, those in the highest quintile of SSB intake had a 78 percent increased risk of developing type I endometrial cancer while those who reported at least some SSB consumption had “a statistically significant 47 [percent] higher risk.” The study’s authors also noted in a December 4, 2013, press release that “previous studies have shown increasing consumption of sugar sweetened beverages has paralleled the increase…
Canadian researchers have warned that many off-the-shelf brewed teas purportedly contain lead in excess of levels considered safe for pregnant and lactating women. Gerry Schwarlfenberg, et al., “The Benefits and Risks of Consuming Brewed Tea: Beware of Toxic Element Contamination,” Journal of Toxicology, December 2013. Using 30 samples of black, green, white, and oolong teas obtained from supermarkets and health food stores, the study’s authors steeped the teas using one tea bag and 250 mL of distilled water for 3-4 minutes and 15-17 minutes. The results evidently showed that “all brewed teas contained lead,” with 73 percent of teas brewed for three minutes and 83 percent of teas brewed for 15 minutes having lead levels ranging from 0.1 µgm/L to 4.39 µgm/L. According to the study, California’s Proposition 65 currently sets an acceptable limit for lead in reproductive health at 0.5 µgm/L per day. In addition, the study notes that…
A recent study has reportedly linked high phosphorus consumption to increased all-cause mortality in a healthy adult population, raising concerns about the use of inorganic phosphorus additives in processed food. Alex Chang, et al., “High dietary phosphorus intake is associated with all-cause mortality: results from NHANES-III,” American Journal of Clinical Nutrition, November 2013. Relying on 24-hour dietary recall surveys from 9,686 participants in the National Health and Nutrition Examination Survey – III, researchers noted an association between high phosphorus intake and all-cause mortality for individuals who consumed more than 1,400 milligrams of phosphorus per day. “The relation between increasing absolute phosphorus intake and mortality appeared flat until a threshold of ~1400 mg/d, which is an amount of phosphorus consumption that is twice the adult US RDA [recommended daily allowance],” reported the study’s authors. Although they acknowledged that their results did not distinguish between organic and inorganic sources of phosphorus, they…
