1. Study suggests you are what you think you eat

    September 20, 2017 by Ashley

    From the British Psychological Society (BPS) press release:

    Despite eating the same breakfast, made from the same ingredients, people consumed more calories throughout the day when they believed that one of the breakfasts was less substantial than the other.

    The research, funded by the Rural and Environment Science and Analytical Services at the Rowett Institute, is the key finding of research led by Steven Brown from Sheffield Hallam University which is being presented today at the annual conference of the British Psychological Society’s Division of Health Psychology.

    Previous studies have investigated the link between how filling we expect liquids (e.g. drinks) or semi-solids (e.g. smoothies/soups) to be and people’s subsequent feelings of hunger up to three hours later.

    These initial expectations have also been shown to be an important determinant of how much people eat at a meal provided a short time later. The current research shows that a similar effect can be seen when using solid foods (i.e. an omelette) and that the influence of those expectations is still present after a longer period of time (four hours later and the total day’s calorific intake).

    A total of 26 participants took part. Over two visits, participants believed they were eating either a two or four egg omelette for breakfast. However, both of the omelettes actually contained three eggs.

    When the participants believed that the omelette was smaller they reported themselves to be significantly hungrier after two hours, they consumed significantly more of a pasta lunch and, in total, consumed significantly more calories throughout the day than when the same participants believed that they were eating a larger omelette.

    Steven Brown said, “Previous studies have shown that a person’s expectations can have an impact on their subsequent feelings of hunger and fullness and, to a degree, their later calorie consumption. Our work builds on this with the introduction of solid food and measured people’s subsequent consumption four hours later, a period of time more indicative of the gap between breakfast and lunch.

    “We were also able to measure participants’ consumption throughout the rest of the day and found that total intake was lower when participants believed that they had eaten a larger breakfast.

    “As part of the study, we were able to take blood samples from participants throughout their visits. Having analysed levels of ghrelin, a known hunger hormone, our data also suggest that changes in reported hunger and the differences in later consumption are not due to a differences in participants’ physical response to the food.

    Therefore, memory for prior consumption, as opposed to physiological factors, may be a better target for investigating why expectations for a meal have an effect on subsequent feelings of hunger and calorie intake.”


  2. Study finds active ingredient in sugarcane may help with stress-related insomnia

    September 18, 2017 by Ashley

    From the University of Tsukuba press release:

    Everyone empirically knows that stressful events certainly affect sound sleep. Scientists in the Japanese sleep institute found that the active component rich in sugarcane and other natural products may ameliorate stress and help having sound sleep.

    In today’s world ever-changing environment, demanding job works and socio-economic factors enforces sleep deprivation in human population. Sleep deprivation induces tremendous amount of stress, and stress itself is one of the major factors responsible for sleep loss or difficulty in falling into sleep. Currently available sleeping pills does not address stress component and often have severe side effects. Sleep loss is also associated with certain other diseases including obesity, cardiovascular diseases, depression, anxiety, mania deficits etc.

    The research group led by Mahesh K. Kaushik and Yoshihiro Urade of the International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, found that octacosanol reduces stress and restores stress-affected sleep back to normal.

    Octacosanol is abundantly present in various everyday foods such as sugarcane (thin whitish layer on surface), rice bran, wheat germ oil, bee wax etc. The crude extract is policosanol, where octacosanol is the major constituent. Policosanol and octacosanol have already been used in humans for various other medical conditions.

    In the current study, authors made an advancement and investigated the effect of octacosanol on sleep regulation in mildly stressed mice by oral administration. Octacosanol reduced corticosterone level in blood plasma, which is a stress marker. The octacosanol-administered mice also showed normal sleep, which was previously disturbed due to stress. They therefore claim that the octacosanol mitigates stress in mice and restores stress-affected sleep to normal in mice. The sleep induced by octacosanol was similar to natural sleep and physiological in nature. However, authors also claimed that octacosanol does not affect sleep in normal animals. These results clearly demonstrated that octacosanol is an active compound that has potential to reduce stress and to increase sleep, and it could potentially be useful for the therapy of insomnia caused by stress. Octacosanol can be considered safe for human use as a therapy, because it is a food-based compound and believed to show no side effects.

    Octacosanol/policosanol supplements are used by humans for functions such as lipid metabolism, cholesterol lowering or to provide strength. However, well-planned clinical studies need to be carried out to confirm its effect on humans for its stress-mitigation and sleep-inducing potentials. “Future studies include the identification of target brain area of octacosanol, its BBB permeability, and the mechanism via which octacosanol lowers stress,” Kaushik says.


  3. Nutrition has benefits for brain network organization

    September 15, 2017 by Ashley

    From the University of Illinois at Urbana-Champaign press release:

    Nutrition has been linked to cognitive performance, but researchers have not pinpointed what underlies the connection. A new study by University of Illinois researchers found that monounsaturated fatty acids — a class of nutrients found in olive oils, nuts and avocados — are linked to general intelligence, and that this relationship is driven by the correlation between MUFAs and the organization of the brain’s attention network.

    The study of 99 healthy older adults, recruited through Carle Foundation Hospital in Urbana, compared patterns of fatty acid nutrients found in blood samples, functional MRI data that measured the efficiency of brain networks, and results of a general intelligence test. The study was published in the journal NeuroImage.

    “Our goal is to understand how nutrition might be used to support cognitive performance and to study the ways in which nutrition may influence the functional organization of the human brain,” said study leader Aron Barbey, a professor of psychology. “This is important because if we want to develop nutritional interventions that are effective at enhancing cognitive performance, we need to understand the ways that these nutrients influence brain function.”

    “In this study, we examined the relationship between groups of fatty acids and brain networks that underlie general intelligence. In doing so, we sought to understand if brain network organization mediated the relationship between fatty acids and general intelligence,” said Marta Zamroziewicz, a recent Ph.D. graduate of the neuroscience program at Illinois and lead author of the study.

    Studies suggesting cognitive benefits of the Mediterranean diet, which is rich in MUFAs, inspired the researchers to focus on this group of fatty acids. They examined nutrients in participants’ blood and found that the fatty acids clustered into two patterns: saturated fatty acids and MUFAs.

    “Historically, the approach has been to focus on individual nutrients. But we know that dietary intake doesn’t depend on any one specific nutrient; rather, it reflects broader dietary patterns,” said Barbey, who also is affiliated with the Beckman Institute for Advanced Science and Technology at Illinois.

    The researchers found that general intelligence was associated with the brain’s dorsal attention network, which plays a central role in attention-demanding tasks and everyday problem solving. In particular, the researchers found that general intelligence was associated with how efficiently the dorsal attention network is functionally organized used a measure called small-world propensity, which describes how well the neural network is connected within locally clustered regions as well as across globally integrated systems.

    In turn, they found that those with higher levels of MUFAs in their blood had greater small-world propensity in their dorsal attention network. Taken together with an observed correlation between higher levels of MUFAs and greater general intelligence, these findings suggest a pathway by which MUFAs affect cognition.

    “Our findings provide novel evidence that MUFAs are related to a very specific brain network, the dorsal attentional network, and how optimal this network is functionally organized,” Barbey said. “Our results suggest that if we want to understand the relationship between MUFAs and general intelligence, we need to take the dorsal attention network into account. It’s part of the underlying mechanism that contributes to their relationship.”

    Barbey hopes these findings will guide further research into how nutrition affects cognition and intelligence. In particular, the next step is to run an interventional study over time to see whether long-term MUFA intake influences brain network organization and intelligence.

    “Our ability to relate those beneficial cognitive effects to specific properties of brain networks is exciting,” Barbey said. “This gives us evidence of the mechanisms by which nutrition affects intelligence and motivates promising new directions for future research in nutritional cognitive neuroscience.”


  4. Eating triggers endorphin release in the brain

    September 12, 2017 by Ashley

    From the University of Turku press release:

    Finnish researchers have revealed how eating stimulates brain’s endogenous opioid system to signal pleasure and satiety.

    The recent results obtained by researchers from Turku PET Centre have revealed that eating leads to widespread opioid release in the brain, likely signalling feelings of satiety and pleasure.

    Eating a delicious pizza led to significant increase of pleasant feelings, whereas consumption of calorie-matched nutritional drink did not. However, both types of meals induced significant release of endogenous opioids in the brain.

    Opioids are associated with pleasure and euphoria. The study revealed that a significant amount of endorphins is released in the entire brain after eating the pizza and, surprisingly, even more are released after the consumption of the tasteless nutritional drink. The magnitude of the opioid release was independent of the pleasure associated with eating. According to the researchers, it is likely that the endogenous opioid system regulates both feelings of pleasure and satiety.

    -The opioid system regulates eating and appetite, and we have previously found that its dysfunctions are a hallmark of morbid obesity. The present results suggest that overeating may continuously overstimulate the opioid system, thus directly contributing to development of obesity. These findings open new opportunities for treating overeating and the development of obesity, says Professor Lauri Nummenmaa from Turku PET Centre.

    – It was a surprise that endorphins are released in the entire brain and that the nutritional drink had a larger impact. This creates a basis for future research and hopefully we will find ways to study and describe the development and predictors of addiction, obesity and eating disorders, says Researcher, M.D., PhD. Jetro Tuulari.

    The study was conducted using positron emission tomography (PET). The participants were injected with a radioactive compound binding to their brain’s opioid receptors. Radioactivity in the brain was measured three times with the PET camera: after a palatable meal (pizza), after a non-palatable meal (liquid meal) and after an overnight fast.

    The research was funded by the Academy of Finland.


  5. Study suggests excess of methionine during pregnancy may play a role in schizophrenia

    August 29, 2017 by Ashley

    From the University of California – Irvine press release:

    An abundance of an amino acid called methionine, which is common in meat, cheese and beans, may provide new clues to the fetal brain development that can manifest in schizophrenia, University of California, Irvine pharmacology researchers report in the journal Molecular Psychiatry.

    The findings point to the role methionine overload can play during pregnancy and suggest that targeting the effects of this amino acid may lead to new antipsychotic drugs.

    The UCI study also provides detailed information on the neural developmental mechanisms of the methionine effect, which results in changes in the expression of several genes important to healthy brain growth and, in particular, to one linked to schizophrenia in humans.

    Amal Alachkar and colleagues based their approach on studies from the 1960s and 1970s in which schizophrenic patients injected with methionine experienced worsened symptoms. Knowing that schizophrenia is a developmental disorder, the UCI team hypothesized that administering three times the normal daily input of methionine to pregnant mice may produce pups that have also schizophrenia-like deficits, which is what occurred.

    The pups of the injected mothers displayed deficits in nine different tests encompassing the three schizophrenia-like symptoms behaviors — “positive” symptoms of overactivity and stereotypy, “negative” symptoms of human interaction deficits, and “cognitive impairments” memory loss.

    The research team treated the mice with anti-schizophrenic drugs well used in therapy. A drug that in schizophrenics treats mostly the positive symptoms (haloperidol) did the same in the mice, and a drug that treat preferentially the negative symptoms and the cognitive impairments (clozapine) did the same.

    Alachkar, an associate adjunct professor of pharmacology, said that the study is the first to present a mouse model based on methionine-influenced neural development that leads to schizophrenic-like behaviors.

    “This mouse model provides much broader detail of biological processes of schizophrenia and thus reflect much better the disorder than in the animal models presently widely used in drug discovery,” said Olivier Civelli, chair and professor of pharmacology and an author on the paper.

    “Our study also agrees with the saying, ‘we are what our mothers ate’,” Alachkar added. “Methionine is one of the building blocks of proteins. It is not synthesized by our bodies, and it needs to be ingested. Our study points at the very important role of excess dietary methionine during pregnancy in fetal development, which might have a long-lasting influence on the offspring. This is a very exciting area of research that we hope can be explored in greater depth.”


  6. Lutein, found in leafy greens, may counter cognitive aging

    August 19, 2017 by Ashley

    From the University of Illinois at Urbana-Champaign press release:

    Spinach and kale are favorites of those looking to stay physically fit, but they also could keep consumers cognitively fit, according to a new study from University of Illinois researchers.

    The study, which included 60 adults aged 25 to 45, found that middle-aged participants with higher levels of lutein — a nutrient found in green leafy vegetables such as spinach and kale, as well as avocados and eggs — had neural responses that were more on par with younger individuals than with their peers. The findings were published in the journal Frontiers in Aging Neuroscience.

    “Now there’s an additional reason to eat nutrient-rich foods such as green leafy vegetables, eggs and avocados,” said Naiman Khan, a professor of kinesiology and community health at Illinois. “We know these foods are related to other health benefits, but these data indicate that there may be cognitive benefits as well.”

    Most other studies have focused on older adults, after there has already been a period of decline. The Illinois researchers chose to focus on young to middle-aged adults to see whether there was a notable difference between those with higher and lower lutein levels.

    “As people get older, they experience typical decline. However, research has shown that this process can start earlier than expected. You can even start to see some differences in the 30s,” said Anne Walk, a postdoctoral scholar and first author of the paper. “We want to understand how diet impacts cognition throughout the lifespan. If lutein can protect against decline, we should encourage people to consume lutein-rich foods at a point in their lives when it has maximum benefit.”

    Lutein is a nutrient that the body can’t make on its own, so it must be acquired through diet. Lutein accumulates in brain tissues, but also accumulates in the eye, which allows researchers to measure levels without relying on invasive techniques.

    The Illinois researchers measured lutein in the study participants’ eyes by having participants look into a scope and respond to a flickering light. Then, using electrodes on the scalp, the researchers measured neural activity in the brain while the participants performed a task that tested attention.

    “The neuro-electrical signature of older participants with higher levels of lutein looked much more like their younger counterparts than their peers with less lutein,” Walk said. “Lutein appears to have some protective role, since the data suggest that those with more lutein were able to engage more cognitive resources to complete the task.”

    Next, Khan’s group is running intervention trials, aiming to understand how increased dietary consumption of lutein may increase lutein in the eye, and how closely the levels relate to changes in cognitive performance.

    “In this study we focused on attention, but we also would like to understand the effects of lutein on learning and memory. There’s a lot we are very curious about,” Khan said.


  7. Green tea ingredient may ameliorate memory impairment, brain insulin resistance, and obesity

    August 16, 2017 by Ashley

    From the Federation of American Societies for Experimental Biology press release:

    A study published online in The FASEB Journal, involving mice, suggests that EGCG (epigallocatechin-3-gallate), the most abundant catechin and biologically active component in green tea, could alleviate high-fat and high-fructose (HFFD)-induced insulin resistance and cognitive impairment. Previous research pointed to the potential of EGCG to treat a variety of human diseases, yet until now, EGCG’s impact on insulin resistance and cognitive deficits triggered in the brain by a Western diet remained unclear.

    “Green tea is the second most consumed beverage in the world after water, and is grown in at least 30 countries,” said Xuebo Liu, Ph.D., a researcher at the College of Food Science and Engineering, Northwest A&F University, in Yangling, China. “The ancient habit of drinking green tea may be a more acceptable alternative to medicine when it comes to combatting obesity, insulin resistance, and memory impairment.”

    Liu and colleagues divided 3-month-old male C57BL/6J mice into three groups based on diet:

    1) a control group fed with a standard diet,

    2) a group fed with an HFFD diet, and 3) a group fed with an HFFD diet and 2 grams of EGCG per liter of drinking water.

    For 16 weeks, researchers monitored the mice and found that those fed with HFFD had a higher final body weight than the control mice, and a significantly higher final body weight than the HFFD+EGCG mice. In performing a Morris water maze test, researchers found that mice in the HFFD group took longer to find the platform compared to mice in the control group. The HFFD+EGCG group had a significantly lower escape latency and escape distance than the HFFD group on each test day. When the hidden platform was removed to perform a probe trial, HFFD-treated mice spent less time in the target quadrant when compared with control mice, with fewer platform crossings. The HFFD+EGCG group exhibited a significant increase in the average time spent in the target quadrant and had greater numbers of platform crossings, showing that EGCG could improve HFFD-induced memory impairment.

    “Many reports, anecdotal and to some extent research-based, are now greatly strengthened by this more penetrating study,” said Thoru Pederson, Ph.D., Editor-in-Chief of The FASEB Journal.


  8. Mediterranean-style diets linked to better brain function in older adults

    August 12, 2017 by Ashley

    From the American Geriatrics Society press release:

    Eating foods included in two healthy diets — the Mediterranean or the MIND diet — is linked to a lower risk for memory difficulties in older adults, according to a study published in the Journal of the American Geriatrics Society.

    The Mediterranean diet is rich in fruits, vegetables, whole grains, beans, potatoes, nuts, olive oil and fish. Processed foods, fried and fast foods, snack foods, red meat, poultry and whole-fat dairy foods are infrequently eaten on the Mediterranean diet.

    The MIND diet is a version of the Mediterranean diet that includes 15 types of foods. Ten are considered “brain-healthy:” green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, seafood, poultry, olive oil, and wine. Five are considered unhealthy: red meat, butter and stick margarine, cheese, pastries, sweets and fried/fast foods.

    Researchers examined information from 5,907 older adults who participated in the Health and Retirement Study. The participants filled out questionnaires about their eating habits. Researchers then measured the participants’ cognitive abilities — mostly on their memory and attention skills.

    The researchers compared the diets of participants to their performance on the cognitive tests. They found that older people who ate Mediterranean and MIND-style diets scored significantly better on the cognitive function tests than those who ate less healthy diets. In fact, older people who ate a Mediterranean-style diet had 35% lower risk of scoring poorly on cognitive tests. Even those who ate a moderate Mediterranean-style diet had 15% lower risk of doing poorly on cognitive tests. The researchers noted similar results for people who ate MIND-style diets.

    This study suggests that eating Mediterranean and MIND-style diets is linked to better overall cognitive function in older adults, said the researchers. What’s more, older adults who followed these healthy diets had lower risks for having cognitive impairment in later life, noted the researchers.


  9. High-fat ice cream may not necessarily mean tastier ice cream

    August 6, 2017 by Ashley

    From the Penn State press release:

    Even though ice cream connoisseurs may insist that ice cream with more fat tastes better, a team of Penn State food scientists found that people generally cannot tell the difference between fat levels in ice creams.

    In a series of taste tests, participants were unable to distinguish a 2 percent difference in fat levels in two vanilla ice cream samples as long as the samples were in the 6 to 12 percent fat-level range. While the subjects were able to detect a 4 percent difference between ice cream with 6 and 10 percent fat levels, they could not detect a 4 percent fat difference in samples between 8 and 12 percent fat.

    “I think the most important finding in our study was that there were no differences in consumer acceptability when changing fat content within a certain range,” said Laura Rolon, a former graduate student in food science and lead author of the study. “There is a preconception of ‘more fat is better,’ but we did not see it within our study.”

    The researchers, who released their findings in a recent issue of the Journal of Dairy Science, also found that fat levels did not significantly sway consumers’ preferences in taste. The consumers’ overall liking of the ice cream did not change when fat content dropped from 14 percent to 6 percent, for example.

    “Was there a difference in liking — that was our primary question — and could they tell the difference was our secondary question,” said Robert Roberts, professor and head of the food science department.

    John Hayes, associate professor of food science and director of the sensory evaluation center, said that perception and preference are often two separate questions in food science.

    “Another example of this is how some people might like both regular lemonade and pink lemonade equally,” said Hayes. “They can tell the difference when they taste the different lemonades, but still like them both. Differences in perception and differences in liking are not the same thing.”

    The study may challenge some ice cream marketing that suggests ice cream with high fat levels are higher quality and better tasting products, according to researchers.

    “People think premium ice cream means only high fat ice cream, but it doesn’t,” said Roberts.

    Because there are only slight differences in taste perception and preferences at certain fat levels, ice cream manufacturers may have more latitude in adjusting their formulas to help control costs and create products for customers with certain dietary restrictions without sacrificing taste, according to the researchers.

    “Fat is always the most expensive bulk ingredient of ice cream and so when you’re talking about premium ice cream, it tends to have a higher fat content and cost more, while the less expensive economy brands tend to have lower fat content,” said John Coupland, professor of food science.

    The researchers recruited a total of 292 regular ice-cream consumers to take part in the blind taste tests to determine their overall acceptability of various fat levels in fresh ice cream and to see if they could tell the difference between samples. They changed the fat content by adjusting the levels of cream and by adding maltodextrin, a mostly tasteless, starch-based material that is used to add bulk to products, such as frozen desserts.

    Maltodextrin is not necessarily a healthy fat replacement alternative, according to the researchers.

    “We don’t want to give the impression that we were trying to create a healthier type of ice cream,” said Coupland. “But, if you were in charge of an ice cream brand this information may help you decide if you are getting any advantage of having high fat in your product, or whether it’s worth the economic cost, or worth the brand risk to change the fat level of your ice cream.”

    During storage, ice crystals can increase in size, which affects the quality of the ice cream. Because of this effect, the researchers also studied stored samples and found no significant difference in preference after storage.

    Hayes said that Penn State and the College of Agriculture Sciences’ focus on interdisciplinary research was critical for this work.

    “I think this shows how interdisciplinary and translational food science is,” Hayes said. “You take a physical chemist, a behavioral scientist and someone who knows ice cream processing and put us all together and you can investigate questions like these.”


  10. Are sugary drink interventions changing people’s behavior?

    August 4, 2017 by Ashley

    From the University of Leeds press release:

    An evaluation of efforts designed to reduce how many sugary drinks we consume shows some success in changing younger people’s habits but warns they cannot be the only way to cut consumption.

    Nutritionists at the University of Leeds have carried out the first comprehensive review of interventions to reduce sugary drinks consumption. The team analysed 40 studies with 16,500 participants across three age groups: children, teenagers and adults.

    Their study, published in the Obesity Reviews journal, found that children participating in these programmes reduced their sugary drink intake by around 30%, removing nearly 2.5 teaspoons of sugar from a child’s average intake of 16 teaspoons per day.

    Interventions aimed at teenagers saw sugary drink consumption reduced by nearly 10%. However, there was almost no measureable change in adults participating in these programmes.

    The evaluation highlighted some of the successful behavioural change techniques used, but warned that to achieve significant change in sugary drink consumption additional measures are needed.

    First author, Elisa Vargas-Garcia from the School of Food Science and Nutrition, said: “On average sugar intake is two to three times higher than recommended across all age groups. We evaluated these programmes to see if they were causing real changes in behaviour.

    “School is a common place to target obesity-related behaviour. However, in the programmes aimed at younger populations we found that the interventions that took place in the home were actually more effective.”

    Lead author Professor Janet Cade, Professor of Nutritional Epidemiology and Public Health at Leeds, said: “But while the children and teenage programmes can claim some success, the lack of effectiveness in interventions for adults is worrying. Interventions alone cannot be relied upon to affect sugary drink behaviours.

    Scientists, public health officials and policy makers need to work together to establish the best courses of action, from increasing the availability of water in and around schools to introducing the levy on sugary drinks companies.”

    The only intervention component associated with significant results was when there was a role model to demonstrate ‘good’ behaviour towards sugary drinks. In these cases programme participants are able to model someone they like or admire, such as parents, causing a change in behaviour.

    The programmes aimed at children and teenagers typically incorporated a number of different components including group-led or class-based sessions that taught about the negative health consequences of drinking too many sugary drinks and targeting unhealthy diet behaviours and promoting water as a drink alternative.

    Some of the programmes included parental support and worked to change the environment by adding water fountains and filters at schools.

    The programmes aimed at adults also included nutritional advice sessions to help better understand food labels and how to choose healthier drinks. Several of the adult programmes including setting and monitoring personal goals such as making pledges to drink fewer fizzy drinks.

    Co-author Dr Charlotte Evans, also from the School of Food Science and Nutrition at Leeds said “It’s estimated that children and adults get about a quarter of their sugar from sugary drinks and these drinks are linked with health risks such as type 2 diabetes, obesity and tooth decay.

    “This systematic review is one of many actions needed to plan and implement the best methods to change behaviours and attitudes towards sugary drinks. We also need action to improve the wider environment by making sugary drinks more expensive, less available and less desirable through taxation, reformulation and reduced marketing.”

    There are currently a number of public health initiatives to reduce sugary drink consumption. Some of these include campaigns to increase public awareness about the sugar content and the consequences of heavy consumption as well as restricting the availability of sugary drinks and promoting water as an alternative.

    The government is also planning on introducing a levy on companies producing sugary drinks starting in April 2018 where drinks with more than 5g of sugars per litre will be taxed. This is encouraging companies to reformulate their drinks so they contain less than 5% sugar.