1. Study examines link between job stress, junk food and sleep

    July 10, 2017 by Ashley

    From the Michigan State University press release:

    Stress during the workday can lead to overeating and unhealthy food choices at dinnertime, but there could be a buffer to this harmful pattern.

    A good night’s sleep can serve as a protecting factor between job stress and unhealthy eating in the evening, indicates a new study co-authored by a Michigan State University scholar.

    The study, published online in the Journal of Applied Psychology, is one of the first to investigate how psychological experiences at work shape eating behaviors.

    “We found that employees who have a stressful workday tend to bring their negative feelings from the workplace to the dinner table, as manifested in eating more than usual and opting for more junk food instead of healthy food,” said Chu-Hsiang “Daisy” Chang, MSU associate professor of psychology and study co-author.

    “However, another key finding showed how sleep helped people deal with their stressful eating after work,” she added. “When workers slept better the night before, they tended to eat better when they experienced stress the next day.”

    The research involved two studies of 235 total workers in China. One study dealt with information-technology employees who regularly experienced high workload and felt there was never enough time in the workday. The second study involved call-center workers who often got stressed from having to deal with rude and demanding customers.

    In both cases, workday stress was linked to employees’ negative mood while on the job, which in turn was linked to unhealthy eating in the evening, said Yihao Liu, co-author and assistant professor at the University of Illinois.

    The study proposed two potential explanations, Liu said.

    “First, eating is sometimes used as an activity to relieve and regulate one’s negative mood, because individuals instinctually avoid aversive feelings and approach desire feelings,” he said. “Second, unhealthy eating can also be a consequence of diminished self-control. When feeling stressed out by work, individuals usually experience inadequacy in exerting effective control over their cognitions and behaviors to be aligned with personal goals and social norms.”

    Chang said the finding that sleep protects against unhealthy eating following workday stress shows how the health behaviors are related.

    “A good night’s sleep can make workers replenished and feel vigorous again, which may make them better able to deal with stress at work the next day and less vulnerable to unhealthy eating,” she said.

    To address the problem, companies should emphasize the importance of health management for their employees and consider sleep-awareness training and flexible scheduling.

    Companies should also reconsider the value of food-related job perks, which have become very common.

    “Food-related perks may only serve as temporary mood-altering remedies for stressed employees,” Chang said, “and failure to address the sources of the work stress may have potential long-term detrimental effects on employee health.”


  2. Extra-virgin olive oil preserves memory, protects brain against Alzheimer’s

    July 4, 2017 by Ashley

    From the Temple University Health System press release:

    The Mediterranean diet, rich in plant-based foods, is associated with a variety of health benefits, including a lower incidence of dementia. Now, researchers at the Lewis Katz School of Medicine at Temple University (LKSOM) have identified a specific ingredient that protects against cognitive decline: extra-virgin olive oil, a major component of the Mediterranean diet. In a study published online June 21 in the Annals of Clinical and Translational Neurology, the researchers show that the consumption of extra-virgin olive oil protects memory and learning ability and reduces the formation of amyloid-beta plaques and neurofibrillary tangles in the brain — classic markers of Alzheimer’s disease.

    The Temple team also identified the mechanisms underlying the protective effects of extra-virgin olive oil. “We found that olive oil reduces brain inflammation but most importantly activates a process known as autophagy,” explained senior investigator Domenico Praticò, MD, Professor in the Departments of Pharmacology and Microbiology and the Center for Translational Medicine at LKSOM. Autophagy is the process by which cells break down and clear out intracellular debris and toxins, such as amyloid plaques and tau tangles.

    “Brain cells from mice fed diets enriched with extra-virgin olive oil had higher levels of autophagy and reduced levels of amyloid plaques and phosphorylated tau,” Dr. Praticò said. The latter substance, phosphorylated tau, is responsible for neurofibrillary tangles, which are suspected of contributing to the nerve cell dysfunction in the brain that is responsible for Alzheimer’s memory symptoms.

    Previous studies have suggested that the widespread use of extra-virgin olive oil in the diets of people living in the Mediterranean areas is largely responsible for the many health benefits linked to the Mediterranean diet. “The thinking is that extra-virgin olive oil is better than fruits and vegetables alone, and as a monounsaturated vegetable fat it is healthier than saturated animal fats,” according to Dr. Praticò.

    In order to investigate the relationship between extra-virgin olive oil and dementia, Dr. Praticò and colleagues used a well-established Alzheimer’s disease mouse model. Known as a triple transgenic model, the animals develop three key characteristics of the disease: memory impairment, amyloid plagues, and neurofibrillary tangles.

    The researchers divided the animals into two groups, one that received a chow diet enriched with extra-virgin olive oil and one that received the regular chow diet without it. The olive oil was introduced into the diet when the mice were six months old, before symptoms of Alzheimer’s disease begin to emerge in the animal model.

    In overall appearance, there was no difference between the two groups of animals. However, at age 9 months and 12 months, mice on the extra virgin olive oil-enriched diet performed significantly better on tests designed to evaluate working memory, spatial memory, and learning abilities.

    Studies of brain tissue from both groups of mice revealed dramatic differences in nerve cell appearance and function.

    “One thing that stood out immediately was synaptic integrity,” Dr. Praticò said. The integrity of the connections between neurons, known as synapses, were preserved in animals on the extra-virgin olive oil diet. In addition, compared to mice on a regular diet, brain cells from animals in the olive oil group showed a dramatic increase in nerve cell autophagy activation, which was ultimately responsible for the reduction in levels of amyloid plaques and phosphorylated tau.

    “This is an exciting finding for us,” explained Dr. Praticò. “Thanks to the autophagy activation, memory and synaptic integrity were preserved, and the pathological effects in animals otherwise destined to develop Alzheimer’s disease were significantly reduced. This is a very important discovery, since we suspect that a reduction in autophagy marks the beginning of Alzheimer’s disease.”

    Dr. Praticò and colleagues plan next to investigate the effects of introducing extra-virgin olive oil into the diet of the same mice at 12 months of age, when they have already developed plaques and tangles. “Usually when a patient sees a doctor for suspected symptoms of dementia, the disease is already present,” Dr. Praticò added. “We want to know whether olive oil added at a later time point in the diet can stop or reverse the disease.”


  3. Study suggests gut-based treatments for autism

    July 3, 2017 by Ashley

    From the Frontiers press release:

    Experts have called for large-scale studies into altering the make-up of bacteria in the gut, after a review showed that this might reduce the symptoms of Autism Spectrum Disorder (ASD). Until now, caregivers have relied on rehabilitation, educational interventions and drugs to reduce ASD symptoms, but now researchers suggest that treating this condition could be as simple as changing their diet.

    A review of more than 150 papers on ASD and gut bacteria found that since the 1960s, scientists have been reporting links between the composition of bacteria in the gut and autistic behaviour. The review highlights many studies showing that restoring a healthy balance in gut bacteria can treat ASD symptoms.

    “To date there are no effective therapies to treat this range of brain developmental disorders,” explains Dr Qinrui Li of Peking University, China. “The number of people being diagnosed with ASD is on the rise. As well as being an expensive condition to manage, ASD has a huge emotional and social cost on families of sufferers.”

    The link between the gut and ASD is well-known among sufferers: problems like diarrhea, constipation and flatulence are commonly reported. The root of gastro-intestinal problems like these is an imbalance of “good” and “bad” bacteria in the gut.

    A cheap and effective treatment?

    Many of the papers reviewed support the idea of a gut-brain axis — a way in which factors in the gut can affect processes in the brain. So these gastro-intestinal problems may have a more sinister side. The overgrowth of bad bacteria in the gut inevitably leads to an overproduction of by-products — including toxins. These can make the gut lining more permeable. Then toxins, by-products and even undigested food can get into the bloodstream and travel to the brain.

    In a child under three years old, whose brain is at the height of development, the presence of these chemicals can impair neuro-development, leading to ASD.

    What causes infants to develop an imbalance in the gut microbiota?

    “ASD is likely to be a result of both genetic and environmental factors” explains Dr Li. “The environmental factors include the overuse of antibiotics in babies, maternal obesity and diabetes during pregnancy, how a baby is delivered and how long it is breastfed. All of these can affect the balance of bacteria in an infant’s gut, so are risk factors for ASD.”

    However, the researchers found a significant body of evidence that reverting the gut microbiota to a healthy state can reduce ASD symptoms.

    “Efforts to restore the gut microbiota to that of a healthy person has been shown to be really effective” continues Dr Li. “Our review looked at taking probiotics, prebiotics, changing the diet — for example, to gluten- and casein-free diets, and faecal matter transplants. All had a positive impact on symptoms .”

    These include such things as increased sociability, a reduction in repetitive behaviour, and improved social communication: all hugely beneficial to the life of an ASD sufferer.

    The message of this review is one of positivity. This could well be a breakthrough in the treatment of this disorder. However, the researchers believe that the studies are too few and too small, and that new clinical trials are needed to take this research to the next level.

    “We are encouraged by our findings, but there is no doubt that further work needs to be carried out in this field” says Dr Li. “We need more well-designed and larger-scale studies to support our theory. For now, behavioural therapies remain the best way to treat ASD. We would hope that our review leads to research on the link between the gut microbiota and ASD, and eventually a cheap and effective treatment.”


  4. Poor adolescent diet may influence brain and behavior in adulthood

    July 2, 2017 by Ashley

    From the Society for Neuroscience press release:

    Adolescent male mice fed a diet lacking omega-3 fatty acids show increased anxiety-like behavior and worse performance on a memory task in adulthood, according to new research published in The Journal of Neuroscience. The study suggests adequate nutrition in adolescence is important for the refinement of the adult brain and behavior.

    The structure and function of the brain continue to change throughout adolescence, at the same time that teenagers gain increasing independence and begin to make their own food choices. Since high-calorie, low-quality diets tend to be more affordable than healthy ones, teenagers may opt for foods that lack key nutrients important for brain health such as omega-3 polyunsaturated fatty acids (n-3 PUFAs), which cannot be produced by the human body and must be obtained from foods such as fish and vegetables.

    Oliver Manzoni and colleagues fed mice a balanced diet until early adolescence, when some mice were switched to a diet lacking n-3 PUFAs. Mice fed the poor diet during adolescence had reduced levels of n-3 PUFA in the medial prefrontal cortex and the nucleus accumbens in adulthood compared to control mice. The low-quality diet impaired the brain’s ability to fine-tune connections between neurons in these regions.


  5. Computer game could help children choose healthy food

    May 27, 2017 by Ashley

    From the University of Exeter press release:

    A simple brain-training game could help children choose healthy snacks instead of chocolate and sweets, according to a new study.

    Children who played a seven-minute game devised by University of Exeter psychologists made healthier choices when asked to pick foods afterwards.

    The game involves reacting to images of healthy food by pressing a button, and doing nothing if unhealthy foods are shown.

    “The sight of foods like chocolate can activate reward centres in the brain at the same time as reducing activity in self-control areas,” said Lucy Porter, the lead researcher on the project.

    Our training encourages people to make a new association — when they see unhealthy food, they stop.

    “Many health promotion schemes rely on education and willpower and require a lot of time, staff and money, but our game potentially sidesteps these issues by creating a free, easy tool for families to use at home.

    “The research is at an early stage and we need to investigate whether our game can shift dietary habits in the long-term, but we think it could make a useful contribution.”

    The researchers ran two experiments, and in total more than 200 schoolchildren aged 4-11 were shown images of healthy and unhealthy foods.

    Alongside each image was a cartoon face — happy for healthy food, sad for unhealthy food.

    Children had to hit the spacebar when they saw a happy face, and do nothing if they saw a sad face — they were not told that the game had anything to do with healthy or unhealthy food.

    Afterwards, they played a shopping game where they had to choose a limited number of food items in one minute.

    “We didn’t see a total turnaround in favour of choosing healthy options, but these increased from about 30% of foods chosen to over 50% in children who did the brain training,” said Porter.

    Age did not affect whether the game worked or not, meaning that children as young as four can benefit from playing.

    Meanwhile children in control groups — who were shown happy and sad faces mixed evenly between healthy and unhealthy foods, or images which were not food-related at all — showed no change in food choices.

    Similar research by the study’s senior author, Dr Natalia Lawrence, has already led to the creation of an app which helps adults avoid unhealthy foods and lose weight.

    “It’s encouraging to see that this simple computer game has the potential to improve food choices in young children as well as in adults” she said.

    “As we all know, it’s incredibly important to encourage healthy eating habits from a young age; children in the UK eat on average three times too much sugar and not enough fruit and vegetables.

    “This game is one simple and relatively fun way of trying to redress the balance.”

    Porter added: “This easy game does all the hard work for you. It’s not about learning anything consciously, it’s about working with automatic responses.

    She acknowledges that some people might feel uneasy about this, but she explains: “Playing this game is optional — unlike the constant stream of advertising designed to brainwash children.

    “This game won’t eliminate the effect of junk food advertising or price promotions, but it might give people a little bit of control back.”


  6. Study suggests timing and duration of school lunch and recess related to food choices and physical activity

    May 8, 2017 by Ashley

    From the Experimental Biology 2017 press release:

    A new study finds that the duration and timing of lunch and recess is related to food choices and physical activity of school children. These findings could help schools make policies that promote healthier school lunches and increased physical activity during recess.

    Gabriella McLoughlin, a doctoral student at the University of Illinois, Urbana-Champaign, will present the new research at the American Society for Nutrition Scientific Sessions and annual meeting during the Experimental Biology 2017 meeting, to be held April 22-26 in Chicago.

    “Most research has focused solely on nutritional intake or physical activity during recess,” said Naiman Khan, PhD, assistant professor and leader of the research team. “This is the first study to objectively measure food intake at lunch in conjunction with physical activity and consider the influence of duration and timing.”

    For the study, the researchers assessed the lunch intake and physical activity of 151 fourth and fifth grade students from two low-income schools. Each school scheduled lunch either just before or immediately after recess.

    The researchers found that:

    • Although less food was wasted when recess was held before lunch, children consumed a greater proportion of vegetables when lunch was offered before recess.
    • When children had a longer time for a combined lunch and recess period, children were proportionally more physically active when lunch was offered before recess.
    • When the lunch-recess period was shorter, children were more active when recess was offered before lunch.

    “Overall, our findings suggest that recess and lunch behaviors are interrelated,” said McLoughlin. “However, the specific food choices and activity levels children engage in may be subject to the timing and duration of lunch and recess.” The relationships between food intake at lunch and physical activity were independent of factors previously shown to contribute to recess activity such as a child’s weight status and gender.

    The current guidelines from the Centers for Disease Control and Prevention recommend scheduling recess before lunch to reduce overall food waste. Although the new study also showed reduced food waste when recess is before lunch, the findings suggest that current recommendations may have unintended consequences for the types of foods consumed and could affect physical activity during recess, depending on the duration of the recess-lunch period.

    “We plan to communicate our findings to school teachers, administrators and policymakers to facilitate the implementation of evidence-based policies that support children’s ability to meet their daily physical activity and nutritional recommendations,” said Khan.

    Now that the researchers have extensive data on children’s physical activity patterns and lunch choices, the investigators are seeking federal funding to create feasible and sustainable school interventions based on their findings. They would also like to study whether policies regarding lunch and recess affect risk for obesity, success in academics and other markers of cognitive development in children.


  7. Study explains why food looks even better when dieting

    April 22, 2017 by Ashley

    From the Hiroshima University press release:

    Over recent decades, our understanding of hunger has greatly increased, but this new discovery turns things on their head. Up until now, scientists knew that leptin — a hormone released by fatty tissue, reduces appetite, while ghrelin — a hormone released by stomach tissue makes us want to eat more. These hormones, in turn, activate a host of neurons in the brain’s hypothalamus — the body’s energy control center.

    The discovery of NPGL by Professor Kazuyoshi Ukena of Hiroshima University shows that hunger and energy consumption mechanisms are even more complex than we realized — and that NPGL plays a central role in what were thought to be well-understood processes.

    Professor Ukena first discovered NPGL in chickens after noticing that growing birds grew larger irrespective of diet — suggesting there was more to energy metabolism than meets the eye. Intrigued, the researchers at HU performed a DNA database search to see if mammals might also possess this elusive substance. They found that it exists in all vertebrates — including humans.

    In order to investigate its role, if any, in mammals, Professor Ukena’s team fed three groups of mice, on three distinct diets, to see how NPGL levels are altered. The first set of mice was fed on a low-calorie diet for 24 hours. The second group was fed on a high-fat diet for 5 weeks — and the third lucky group was fed on a high-fat diet, but for an extended period of 13 weeks.

    The mice fed on a low calorie diet were found to experience an extreme increase in NPGL expression, while the 5-week high-fat-diet group saw a large decrease in NPGL expression.

    Further analysis found that mice possess NPGL, and its associated neuron network, in the exact same locations of the brain as those regions already known to control appetite suppression and energy use.

    Professor Ukena proposes that NPGL plays a vital role in these mechanisms — increasing appetite when energy levels fall and reducing appetite when an energy overload is detected — together, helping to keep us at a healthy and functioning weight, and more importantly alive!

    As NPGL levels greatly increased in mice exposed to a low calorie diet, Professor Ukena believes it is an appetite promoter, working in opposition to appetite suppressing hormones such as leptin. Backing this hypothesis up, it was found that mice directly injected with NPGL exhibited a voracious appetite.

    Interestingly NPGL levels, which plummeted in the 5-week-long high-fat-diet mice — fell back to normal levels in mice who gorged themselves for the longer period of 13 weeks.

    It is proposed that exposure to high-fat diets for long periods of time lead to insensitivity to leptin’s appetite-suppressing effects, and so NPGL — even at normal levels — leads to weight gain and obesity, showing that the body can only do so much to keep our weight in check.

    Professor Ukena says that further study is required to understand the interaction of previously known appetite mechanisms with this new kid on the homeostasis block. It does seem however, that we still have a lot to learn about appetite, hunger, and energy consumption. It is hoped that this study into mammalian NPGL adds another piece to the puzzle.

    What is certain — but you knew this already — is that dieting is difficult. The discovery and study of mammalian NPGL helps explain why, and provides a plausible excuse for those whose good intentions fall short.


  8. Study suggests Marmite may affect brain function

    April 12, 2017 by Ashley

    From the University of York press release:

    Scientists at the University of York have discovered a potential link between eating Marmite and activity in the brain, through the apparent increase of a chemical messenger associated with healthy brain function.

    Participants consuming a teaspoon of Marmite every day for a month, compared to a control group who consumed peanut butter, showed a substantial reduction of around 30 per cent in their brain’s response to visual stimuli, measured by recording electrical activity using electroencephalography (EEG).

    Researchers think this may be due to the prevalence of vitamin B12 in Marmite increasing levels of a specific neurotransmitter — known as GABA — in the brain.

    GABA inhibits the excitability of neurons in the brain, with the chemical acting to ‘turn down the volume’ of neural responses in order to regulate the delicate balance of activity needed to maintain a healthy brain.

    As Marmite consumption appears to increase GABA levels, this study is the first to show that dietary intervention may affect these neural processes. GABA imbalances are also associated with a variety of neurological disorders.

    Anika Smith, PhD student in York’s Department of Psychology and first author of the study, said: “These results suggest that dietary choices can affect the cortical processes of excitation and inhibition — consistent with increased levels of GABA — that are vital in maintaining a healthy brain.

    “As the effects of Marmite consumption took around eight weeks to wear off after participants stopped the study, this suggests that dietary changes could potentially have long-term effects on brain function.

    “This is a really promising first example of how dietary interventions can alter cortical processes, and a great starting point for exploring whether a more refined version of this technique could have some medical or therapeutic applications in the future. Of course, further research is needed to confirm and investigate this, but the study is an excellent basis for this.”

    Dr Daniel Baker, Lecturer in the Department of Psychology and senior author of the paper, said: “The high concentration of Vitamin B12 in Marmite is likely to be the primary factor behind results showing a significant reduction in participants’ responsiveness to visual stimuli.

    “Since we’ve found a connection between diet and specific brain processes involving GABA, this research paves the way for further studies looking into how diet could be used as a potential route to understanding this neurotransmitter.

    “Although GABA is involved in various diseases we can make no therapeutic recommendations based on these results, and individuals with a medical condition should always seek treatment from their GP.”


  9. Blueberry concentrate improves brain function in older people

    March 20, 2017 by Ashley

    From the University of Exeter press release:

    Blueberries

    Drinking concentrated blueberry juice improves brain function in older people, according to research by the University of Exeter.

    In the study, healthy people aged 65-77 who drank concentrated blueberry juice every day showed improvements in cognitive function, blood flow to the brain and activation of the brain while carrying out cognitive tests.

    There was also evidence suggesting improvement in working memory.

    Blueberries are rich in flavonoids, which possess antioxidant and anti-inflammatory properties.

    Dr Joanna Bowtell, head of Sport and Health Sciences at the University of Exeter, said: “Our cognitive function tends to decline as we get older, but previous research has shown that cognitive function is better preserved in healthy older adults with a diet rich in plant-based foods.

    “In this study we have shown that with just 12 weeks of consuming 30ml of concentrated blueberry juice every day, brain blood flow, brain activation and some aspects of working memory were improved in this group of healthy older adults.”

    Of the 26 healthy adults in the study, 12 were given concentrated blueberry juice — providing the equivalent of 230g of blueberries — once a day, while 14 received a placebo.

    Before and after the 12-week period, participants took a range of cognitive tests while an MRI scanner monitored their brain function and resting brain blood flow was measured.

    Compared to the placebo group, those who took the blueberry supplement showed significant increases in brain activity in brain areas related to the tests.

    The study excluded anyone who said they consumed more than five portions of fruit and vegetables per day, and all participants were told to stick to their normal diet throughout.

    Previous research has shown that risk of dementia is reduced by higher fruit and vegetable intake, and cognitive function is better preserved in healthy older adults with a diet rich in plant-based foods.

    Flavonoids, which are abundant in plants, are likely to be an important component in causing these effects.


  10. Mediterranean diet may have lasting effects on brain health

    January 13, 2017 by Ashley

    From the American Academy of Neurology (AAN) media release:

    healthy, vital seniorA new study shows that older people who followed a Mediterranean diet retained more brain volume over a three-year period than those who did not follow the diet as closely.

    The study is published in the January 4, 2017, online issue of Neurlogy®, the medical journal of the American Academy of Neurology. But contrary to earlier studies, eating more fish and less meat was not related to changes in the brain.

    The Mediterranean diet includes large amounts of fruits, vegetables, olive oil, beans and cereal grains such as wheat and rice, moderate amounts of fish, dairy and wine, and limited red meat and poultry.

    As we age, the brain shrinks and we lose brain cells which can affect learning and memory,” said study author Michelle Luciano, PhD, of the University of Edinburgh in Scotland. “This study adds to the body of evidence that suggests the Mediterranean diet has a positive impact on brain health.”

    Researchers gathered information on the eating habits of 967 Scottish people around age 70 who did not have dementia. Of those people, 562 had an MRI brain scan around age 73 to measure overall brain volume, gray matter volume and thickness of the cortex, which is the outer layer of the brain. From that group, 401 people then returned for a second MRI at age 76. These measurements were compared to how closely participants followed the Mediterranean diet.

    The participants varied in how closely their dietary habits followed the Mediterranean diet principles. People who didn’t follow as closely to the Mediterranean diet were more likely to have a higher loss of total brain volume over the three years than people who followed the diet more closely. The difference in diet explained 0.5 percent of the variation in total brain volume, an effect that was half the size of that due to normal aging.

    The results were the same when researchers adjusted for other factors that could affect brain volume, such as age, education and having diabetes or high blood pressure [hypertension].

    There was no relationship between grey matter volume or cortical thickness and the Mediterranean diet.

    The researchers also found that fish and meat consumption were not related to brain changes, which is contrary to earlier studies.

    It’s possible that other components of the Mediterranean diet are responsible for this relationship, or that it’s due to all of the components in combination,” Luciano said.

    Luciano noted that earlier studies looked at brain measurements at one point in time, whereas the current study followed people over time.

    “In our study, eating habits were measured before brain volume was, which suggests that the diet may be able to provide long-term protection to the brain,” said Luciano. “Still, larger studies are needed to confirm these results.”