The Brain Cannot Be Fooled By Artificial Sweeteners
Higher Likelihood Of Sugar Consumption Later
The results of the new study imply that it is hard to fool the brain by providing it with ‘energyless’ sweet flavors. Our pleasure in consuming sweet solutions is driven to a great extent by the amount of energy it provides: greater reward in the brain is attributed to sugars compared to artificial sweeteners.
Professor Ivan de Araujo, who led the study at Yale University School of Medicine USA, says: “The consumption of high-calorie beverages is a major contributor to weight gain and obesity, even after the introduction of artificial sweeteners to the market. We believe that the discovery is important because it shows how physiological states may impact on our choices between sugars and sweeteners.
“Specifically, it implies that humans frequently ingesting low-calorie sweet products in a state of hunger or exhaustion may be more likely to ‘relapse’ and choose high calorie alternatives in the future.
“The results suggest that a ‘happy medium’ could be a solution; combining sweeteners with minimal amounts of sugar so that energy metabolism doesn’t drop, while caloric intake is kept to a minimum.”
The study identified a specific physiological brain signal that is critical for determining choice between sugars and sweeteners. This signal regulates dopamine levels – a chemical necessary for reward signalling in the brain – and only arises when sugar is broken down into a form where it is usable as fuel for cells of the body to function.
Research was performed in mice, using a combination of behaviural testing involving sweeteners and sugars, whilst measuring chemical responses in brain circuits for reward. The researchers believe the findings are likely to reflect in humans.
Professor de Araujo says: “According to the data, when we apply substances that interfere with a critical step of the ‘sugar-to-energy pathway’, the interest of the animals in consuming artificial sweetener decreases significantly, along with important reductions in brain dopamine levels.
“This is verified by the fact that when hungry mice – who thus have low sugar levels – are given a choice between artificial sweeteners and sugars, they are more likely to completely switch their preferences towards sugars even if the artificial sweetener is much sweeter than the sugar solution.”
Now that the team know that dopamine cells are critical in sugar/sweetener choice, they hope to identify the associated receptors and pathways in the brain.
artificial sweeteners make you want more real sugar – See more at: http://www.stonehearthnewsletters.com/how-artificial-sweeteners-make-you-want-more-real-sugar-yale-study/nutrition-food-artificial-sweeteners/?goback=%2Egde_161429_member_275835796#%21
October is national depression screening month.
Screening for Mental Health offers National Depression Screening Day programs for the military, colleges and universities, community-based organizations and businesses.
Held annually during Mental Illness Awareness Week in October, National Depression Screening Day (NDSD) raises awareness and screens people for depression and related mood and anxiety disorders.
NDSD is the nation’s oldest voluntary, community-based screening program that provides referral information for treatment. Through the program, more than half a million people each year have been screened for depression since 1991. Take an anonymous depression screening at www.HelpYourselfHelpOthers.org
In a recent Finnish study, subjects with the worst health habits were also the most depressed. Perhaps not surprising, lifestyle evaluations in countries with well established public health services provide a baseline for intervention and corrective action.
Health is our birthright. Health care should also be part of any society’s organizing principles if for no other reason than it works.
Background: The Lapinlahti 2005 study was carried out to explore cardiovascular disease risk factors, lifestyle and quality of life in Lapinlahti residents in eastern Finland. Our aim was to study the association between lifestyle and health-related quality of life (HRQoL) in the community.
Subjects and methods: The present study is based on the baseline data of the followed up (2005–2010) population-based cohort (N = 376, n of males = 184). A trained research nurse measured weight, height, waist circumference and blood pressure. Self-reported HRQoL was measured using a 15D questionnaire. A BDI-21 inventory was used to assess the presence of self-reported depressive symptoms.
Lifestyle factors (nutrition, exercise, smoking and alcohol use) were examined with a structured questionnaire. Each lifestyle item was valued as −1, 0 or 1, depending on how well it corresponded to the recommendations. Based on the index the participants were divided into three lifestyle sum tertiles: I = unhealthy, II = neutral and III = healthy. The age- and sex-adjusted linear trend between the tertiles was tested.
Results: The 15D score had a positive linear relationship with the lifestyle tertiles (P = .0048 for linearity, age- and sex-adjusted). Respectively, self-reported depressive symptoms were less frequent among subjects with a healthier lifestyle (P = .038).
Conclusions: People who are expected to strive most to change their lifestyle have the lowest quality of life and psychological welfare, which should be taken into account in both clinical work and health promotion.
Scand J Public Health 1403494813504837, first published on September 18, 2013 as doi:10.1177/1403494813504837.
- Jorma Savolainen1,2
- Hannu Kautiainen6
- Juhani Miettola1
- Leo Niskanen3,4
- Pekka Mäntyselkä5,6
1Institute of Public Health and Clinical Nutrition, Primary Health Care, School of Medicine, University of Eastern Finland, Kuopio, Finland
2Primary Health Care Unit, Kuopio University Hospital, Kuopio, Finland
3University of Eastern Finland, Faculty of Health Sciences, School of Medicine, Kuopio, Finland
4Finnish Medicines Agency Fimea
5Institute of Clinical Medicine, General Practice, University of Turku, Finland
6Unit of Primary Health Care, Turku University Hospital, Turku, Finland
- Jorma Savolainen, Institute of Public Health and Clinical Nutrition, Primary Health Care, School of Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland. E-mail: firstname.lastname@example.org
11 September 2013 BioMed Central Limited
Forget talking to plants to help them grow, gently rubbing them with your fingers can make them less susceptible to disease, a paper in the open access journal BMC Plant Biology reveals.
Gently rubbing the leaves of thale cress plants (Arabidsopsis thaliana) between thumb and forefinger activates an innate defense mechanism, Floriane L’Haridon and colleagues report. Within minutes, biochemical changes occur, causing the plant to become more resistant to Botrytis cinerea, the fungus that causes grey mould.
Rubbing the leaves is a form of mechanical stress. Plants frequently have to deal with mechanical stress, be it caused by rain, wind, animals or even other plants. Trees growing on windy shorelines, for example, sometimes respond by developing shorter, thicker trunks.
But plants also respond to more delicate forms of mechanical stress, such as touch. Some responses are obvious – the snapping shut of a Venus fly trap, the folding leaflets of a touched touch-me-not plant (Mimosa pudica) – whilst some are more discrete. Plants also launch an arsenal of ‘invisible’ responses to mechanical stress, including changes at the molecular and biochemical level.
Rubbing the thale cress leaves triggered a host of internal changes. Genes related to mechanical stress were activated. Levels of reactive oxygen species increased. And the protective outer layer of the leaf became more permeable, presumably to aid the escape of various biologically active molecules that were detected and which are thought to contribute to the observed immune response. This data could also suggest that the mechanical stress is perceived by mechano-sensors that subsequently initiate resistance.
Similar effects occur when plants are physically wounded. Team members previously showed how physically wounding thale cress increases levels of reactive oxygen species, also triggering a strong, transient immunity to the grey mould fungus. Here they show basically the same thing, but in response to an extremely gentle form of wounding – mechanical stimulation by touch – that unlike wounding, leaves cells intact.
Wounding and rubbing exemplify how plants can react to a situation that in principle could cause them to become more vulnerable. Instead, they react to touch by deploying a carefully-orchestrated defense response, an evolutionary skill that that presumably boosts survival.
Scientists from the University of Southampton have discovered that copper and copper alloys rapidly destroy norovirus – the highly-infectious sickness bug.
Worldwide, norovirus is responsible for more than 267 million cases of acute gastroenteritis every year. In the UK, norovirus costs the National Health Service at least £100 million per year, in times of high incidence, and up to 3,000 people admitted to hospital per year in England.
The virus, for which there is no specific treatment or vaccine, can be contracted from contaminated food or water, person-to-person contact, and contact with contaminated surfaces, meaning surfaces made from copper could effectively shut down one avenue of infection.
The study, which was designed to simulate fingertip-touch contamination of surfaces, showed norovirus was rapidly destroyed on copper and its alloys, with those containing more than 60 per cent copper proving particularly effective.
Copper alloys have previously been shown to be effective antimicrobial surfaces against a range of bacteria and fungi.
The Southampton research reported rapid inactivation of murine norovirus on alloys, containing over 60 per cent copper, at room temperature but no reduction of infectivity on stainless steel dry surfaces in simulated wet fomite and dry touch contamination. The rate of inactivation was initially very rapid and proportional to the copper content of alloy tested. Viral inactivation was not as rapid on brass as previously observed for bacteria but copper-nickel alloy was very effective.
One of the targets of copper toxicity was the viral genome and a reduced number of the gene for a viral encoded protein, VPg (viral-protein-genome-linked), which is essential for infectivity, was observed following contact with copper and brass dry surfaces.
Lead author Sarah Warnes, from the Centre for Biological Sciences at the University of Southampton, says: “The use of antimicrobial surfaces containing copper in clinical and community environments, such as cruise ships and care facilities, could help to reduce the spread of this highly infectious and costly pathogen.
“Copper alloys, although they provide a constant killing surface, should always be used in conjunction with regular and efficient cleaning and decontamination regimes using non-chelating reagents that could inhibit the copper ion activity.”
Co-author Professor Bill Keevil, from the University’s Institute for Life Sciences, adds: “Although the virus was identified over 40 years ago, the lack of methods to assess infectivity has hampered the study of the human pathogen.
“The virus can remain infectious on solid surfaces and is also resistant to many cleaning solutions. That means it can spread to people who touch these surfaces, causing further infections and maintaining the cycle of infection. Copper surfaces, like door handles and taps, can disrupt the cycle and lower the risk of outbreaks.”
The study ‘Inactivation of norovirus on dry copper alloy surfaces’ is published in the latest issue of the journal PLOS ONE.
Previous laboratory studies by the University of Southampton have described the rapid death of bacterial, fungal and viral pathogens such as MRSA on copper alloy surfaces and also prevention of antibiotic resistance horizontal gene transfer between pathogens.
For more information and scientific references, visit www.antimicrobialcopper.org
September 13, 2013
for the Timex/Sodahead.com survey
of how we’re shaping up as far as working out goes.
- 61% of respondents don’t go to a gym to exercise. If they do go to the gym, they want to stay close, as only 11% drive more than 15 minutes to their exercise destination.
- Working out at lunch may not be for everyone, but 27% of respondents are finding time to get in a workout during the work day.
- The most popular type of exercise is running (18%), followed by lifting weights (13%) and biking/hiking/outdoor activities (13%).
- Once Americans finish exercising, it is time to hit the showers. Forty-three percent of survey respondents spend at least 10 to 15 minutes in the shower, 25% spend a whopping 20 to 30 minutes and 10% spend more than a half hour.
The not-so-good news
Out of 665 respondents, 510 (77%) say they usually exercise alone. That’s fine if you have rock-solid willpower, but sometimes you need a nudge to get off the couch. That’s when a buddy is needed. Working out with a friend at least once a week keeps you focused and on track. Here’s how to find the right one.
Feasibility of Enlisting Social Network Members to Promote Weight Loss Among Latinas
While 73% of respondents work out at least once a week — hey, it’s better than nothing — 26% say they do not exercise regularly. We don’t have to go into the importance of regular exercise again, do we?
When it comes to finding time to exercise, Americans may not be “morning people,” as nearly half of respondents say that they don’t exercise in the morning. For those that do work out in the morning, 6 a.m. is the most popular time.