How rosemary scents boost brain performance
Hailed since ancient times for its medicinal properties, we still have a lot to learn about the effects of rosemary. Now researchers writing in Therapeutic Advances in Psychopharmacology, published by SAGE, have shown for the first time that blood levels of a rosemary oil component correlate with improved cognitive performance.
Rosemary (Rosmarinus officinalis) is one of many traditional medicinal plants that yield essential oils. But exactly how such plants affect human behaviour is still unclear. Mark Moss and Lorraine Oliver, working at the Brain, Performance and Nutrition Research Centre at Northumbria University, UK designed an experiment to investigate the pharmacology of 1,8-cineole (1,3,3-trimethyl-2-oxabicyclo[2,2,2]octane), one of rosemary’s main chemical components.
Rosemary (Rosmarinus officinalis) is one of many traditional medicinal plants that yield essential oils. But exactly how such plants affect human behaviour is still unclear. Mark Moss and Lorraine Oliver, working at the Brain, Performance and Nutrition Research Centre at Northumbria University, UK designed an experiment to investigate the pharmacology of 1,8-cineole (1,3,3-trimethyl-2-oxabicyclo[2,2,2]octane), one of rosemary’s main chemical components.
The investigators tested cognitive performance and mood in a cohort of 20 subjects, who were exposed to varying levels of the rosemary aroma. Using blood samples to detect the amount of 1,8-cineole participants had absorbed, the researchers applied speed and accuracy tests, and mood assessments, to judge the rosemary oil’s affects.
Results indicate for the first time in human subjects that concentration of 1,8-cineole in the blood is related to an individual’s cognitive performance – with higher concentrations resulting in improved performance. Both speed and accuracy were improved, suggesting that the relationship is not describing a speed–accuracy trade off.
Meanwhile, although less pronounced, the chemical also had an effect on mood. However, this was a negative correlation between changes in contentment levels and blood levels of 1,8-cineole, which is particularly interesting because it suggests that compounds given off by the rosemary essential oil affect subjective state and cognitive performance through different neurochemical pathways. The oil did not appear to improve attention or alertness, however.
Terpenes like 1,8-cineole can enter the blood stream via the nasal or lung mucosa. As small, fat-soluble organic molecules, terpenes can easily cross the blood–brain barrier. Volatile 1,8-cineole is found in many aromatic plants, including eucalyptus, bay, wormwood and sage in addition to rosemary, and has already been the subject of a number of studies, including research that suggests it inhibits acetylcholinesterase (AChE) and butyrylcholinesterase enzymes, important in brain and central nervous system neurochemistry: rosemary components may prevent the breakdown of the neurotransmitter acetylcholine. “Only contentedness possessed a significant relationship with 1,8-cineole levels, and interestingly to some of the cognitive performance outcomes, leading to the intriguing proposal that positive mood can improve performance whereas aroused mood cannot,” said Moss.
Typically comprising 35-45% by volume of rosemary essential oil, 1,8-cineole may possess direct pharmacological properties. However, it is also possible that detected blood levels simply serve as a marker for relative levels of other active compounds present in rosemary oil, such as rosmarinic acid and ursolic acid, which are present at much lower concentrations. (Source- Therapeutic Advances in Psychopharmacology)
Why Fast-Food Menu Calorie Counts is not helping Consumers
Calorie listings on fast-food chain restaurant menus might meet federal labelling requirements but don't do a good job of helping consumers trying to make healthy meal choices, a new Columbia University School of Nursing (CUSON) study reports. The study, by Elizabeth Gross Cohn, RN, NP, DNSc, assistant professor of nursing at CUSON, and colleagues, was published online in the Journal of Urban Health. The researchers studied the calorie counts for 200 food items on menu boards in fast-food chain restaurants in the New York Harlem . Since 2006, the City has had a standard menu libelling law that includes some, though not all, of the new federal requirements.
"Although most postings were legally compliant, they did not demonstrate utility," the authors say. "Menu postings for individual servings are easily understood, but complex math skills are needed to interpret meals designed to serve more than one person. In some items, calories doubled depending on flavour, and the calorie posting did not give enough information to make healthier selections." The federal health reform law passed in March 2010 requires restaurants with 20 or more locations to provide calorie data and additional nutritional information for menu items and self-service foods. The Food and Drug Administration is now considering how best to guide chain restaurants in posting calorie counts on menu boards. Easily understood calorie listings could be helpful to consumers trying to make healthy food choices, especially in light of the increasing prevalence of obesity among American adults and children. The trend is a particular problem in low-income and inner-city neighborhoods, where sources of more healthful foods might not be as common as fast-food fare. Studies suggest that consumers are generally unaware of, or inaccurately estimate, the number of calories in restaurant foods.
To collect the data, volunteers equipped with digital cameras worked in pairs and canvassed each designated area block by block to identify national restaurant outlets. A total of 70 menus and menu boards from 12 restaurant chains were photographed, and 200 food items rated, using a measure of "practical utility" that the researchers developed to calculate (1) what constitutes a single serving and (2) the number of calories in a single serving. The researchers then combined this measure with current FDA guidelines to develop a seven-item "menu rating tool." The researchers found that, while most restaurants studied have posted calorie counts, in the majority of cases there was insufficient information to make use of them at the point of purchase. One reason for this was that the majority of the items on the menu boards studied were combination meals rather than individual items. Furthermore, it was increasingly difficult to calculate calories per meal when the posting included anything more than an individual unit of measure.
Calorie counts became more challenging as the food items became more complex, especially combination and multi-serving items, which represented the largest percentage of items recorded. These required several mathematical and nutritional calculations, which might be more challenging among low socioeconomic groups in urban areas where fast-food chain restaurants tend to be most concentrated. For example, the study reports, a bucket of chicken was listed as 3,240 to 12,360 calories, but the menu board did not contain enough information to determine the number of pieces of chicken in a serving size. Similarly, a hero combo meal ranged from 500 to 2,080 calories, but no information was provided on how a consumer would order within the lower range of this menu item. Specialty pizzas were offered in wide ranges without a clear explanation as to how they differed, since the calorie count was based on a standard size and standard set of toppings. The authors note that their study was limited to one urban community and did not focus on actual food purchasing behavior but rather on the posted menu boards in chain restaurants. Still, they say, their work suggests the need for more understandable and useful calorie information in posted menus. "As further legislation is developed, we support the FDA in their commitment to having menu boards that are useful at all levels of literacy," they conclude. Specifically, the authors support a system that uses dashes or slashes to more intuitively associate calorie counts to food combinations instead of the current system of ranges. In such a revised system, a breakfast sandwich, for example, would be listed as "egg with ham/bacon/sausage 350/550/750."
"In low-income communities with a high density of chain restaurants, and where educational attainment of consumers may be low, simplifying calorie postings and minimizing the math required to calculate calories would increase menu board utility," they say.
(Source- Journal of Urban Health)
