Consuming protein at night increases blood sugar level in the morning for healthy people, according to new research presented this week at The Physiological Society's virtual early career conference called Future Physiology 2020.
Having high blood sugar levels after eating is linked to health problems, such as diabetes, heart disease and obesity. Previous research has shown that a snack a few hours before a meal can help control blood sugar levels, which may partly explain why the first thing we eat each day (i.e. breakfast) tends to increase blood sugars more than other later meals.
This study investigated whether waking-up at night to consume some protein might keep blood sugars lower the next morning. Surprisingly, the blood sugar response to breakfast was higher when participants had consumed protein rather than plain water at 4 am.
These unexpected findings may be informative for people trying to improve their control of blood sugar levels.
One explanation for the result is that the body does not expect or need much food to be consumed during the night and so the protein itself was turned into sugar. This may result in the body having more carbohydrate already available upon waking such that the energy in the breakfast can less easily be used or stored, so it builds-up more in the blood.
The researchers at the University of Bath studied fifteen healthy young men and women (8 females and 7 males). The participants were woken up at 4 am to drink 300 ml of a water solution, either with or without 63 grams of whey protein.
They then went back to sleep and at 9 am were provided with a standard amount of porridge for breakfast, with blood samples collected for 2 hours afterwards to check the blood glucose response.
The participants then returned to the lab to do the same again a week or so later, but were provided with the other drink at night (4 am) so that we could compare the glucose response to the same breakfast in the same person and see the effects of the night-time protein.
Eleanor Smith, who presented the work, said: "Future research will look at whether this applies to older and overweight people who tend to have more problems controlling their blood sugar levels. It would also be interesting to know to what extent our findings are due to eating at an unusual time or the type of protein consumed."
Higher consumption of fruit, vegetables and whole grain foods are associated with a lower risk of developing type 2 diabetes, according to two studies published by The BMJ today.
The findings suggest that even a modest increase in consumption of these foods as part of a healthy diet could help prevent type 2 diabetes.
In the first study, a team of European researchers examined the association between blood levels of vitamin C and carotenoids (pigments found in colourful fruits and vegetables) with risk of developing type 2 diabetes.
Vitamin C and carotenoid levels are more reliable indicators of fruit and vegetable intake than using dietary questionnaires.
Their findings are based on 9,754 adults who developed new-onset type 2 diabetes and a comparison group of 13,662 adults who remained free of diabetes during follow-up from among 340,234 participants who were taking part in the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct study in eight European countries.
After adjusting for lifestyle, social and dietary risk factors for diabetes, higher blood levels of each of vitamin C and carotenoids and their sum when combined into a "composite biomarker score" were associated with a lower risk of developing type 2 diabetes.
Compared with people who had the lowest composite biomarker score, the risk in people whose biomarker score was in the top 20% of the population was 50% lower. The risk in those with biomarker scores between these two extremes was intermediate.
The researchers calculate that every 66 grams per day increase in total fruit and vegetable intake was associated with a 25% lower risk of developing type 2 diabetes.
In the second study, researchers in the United States examined associations between total and individual whole grain food intake and type 2 diabetes.
Their findings are based on 158,259 women and 36,525 men who were free from diabetes, heart disease and cancer and were taking part in the Nurses' Health Study, Nurses' Health Study II, and Health Professionals Follow-Up Study.
After adjusting for lifestyle and dietary risk factors for diabetes, participants in the highest category for total whole grain consumption had a 29% lower rate of type 2 diabetes compared with those in the lowest category.
For individual whole grain foods, the researchers found that consuming one or more servings a day of whole grain cold breakfast cereal or dark bread was associated with a lower risk of type 2 diabetes (19% and 21% respectively) compared with consuming less than one serving a month.
For other individual whole grains with lower average intake levels, consumption of two or more servings a week compared with less than one serving a month was associated with a 21% lower risk for oatmeal, a 15% lower risk for added bran, and a 12% lower risk for brown rice and wheat germ.
These reductions in risk seemed to plateau at around two servings a day for total whole grain intake, and at around half a serving a day for whole grain cold breakfast cereal and dark bread.
Both studies are observational so can't establish cause, and there's a possibility that some of the results may be due to unmeasured (confounding) factors. However, both studies took account of several well known lifestyle risk factors and markers of dietary quality, and the findings back up other research linking a healthy diet with better health.
As such, both research teams say their findings provide further support for current recommendations to increase fruit, vegetable and whole grain consumption as part of a healthy diet to prevent type 2 diabetes.
And for fruit and vegetables, the findings also suggest that consumption of even a moderately increased amount among populations who typically consume low levels could help to prevent type 2 diabetes.
People who seek novel and powerful sensations and are more prone to taking risks -- and who perceive bitter tastes more intensely -- are more likely to prefer bitter, pale-ale-style beers and drink them more often, according to Penn State sensory researchers, who conducted a study that involved blind taste tests and personality assessments.
The results of the study, which involved more than 100 beer consumers, were unexpected, explained researcher John Hayes, associate professor of food science, because previous research typically indicates that greater perceived bitterness leads to decreased intake of bitter foods and drinks.
"Traditionally, most researchers find that people who experience bitterness more intensely avoid bitter food or drink -- so with heightened bitterness, they like it less, and therefore consume it less," he said. "But here, we find that people who seek higher sensations and are more risk-taking, they like bitter beer such as India pale ales, if they also have greater bitter taste perception."
The connection between food liking and personality has been seen before, noted Hayes, director of Penn State's Sensory Evaluation Center. In a study spearheaded by one of his former doctoral students, his research group in the College of Agricultural Sciences found robust links between the liking of spicy foods and the high-sensation-seeking, risk-taking personality traits. Studies done in Mexico and Italy also have revealed similar findings.
These results highlight the importance of considering personality traits such as sensation seeking when considering the relationship between bitterness perception and the liking and intake of bitter food and beverage products, said lead researcher Molly Higgins, who will receive her doctoral degree in food science this August.
"Our data contradict the classic view that bitterness is merely an aversive sensation that limits intake. We found that increased bitterness perception does not always lead to decreased liking and intake -- rather, it's a positive attribute in some products for some consumers."
In Higgins' study, 109 beer consumers rated liking and intensity of two pale ales and a lager, and the intensity of two bitter solutions -- quinine, the compound that makes tonic water bitter, and hops extract Tetralone -- under blind laboratory conditions. Participants also completed intake and personality questionnaires. A liking ratio for each beer was calculated from each participant's liking for that specific beer and their total liking for all beers.
Participants, about half men and half women, most in their 30s, were classified as weekly, monthly or yearly pale-ale consumers using intake data. Using intensity ratings, personality measures and other parameters, the researchers developed models to predict liking ratios and beer-intake frequency.
A lager beer and two pale-ale-style beers were chosen as the test stimuli. The specific beer samples were selected by research staff following benchtop tasting of various commercial pale-ale-style beers sold in Pennsylvania. To represent the range of bitterness in commercial pale ales, researchers selected one pale ale that was strongly bitter and one that was moderately bitter.
To represent a lager-style beer with low bitterness, research staff selected Budweiser. The pale-ale-style beers used in the study were Founder's All-Day IPA Session Ale as the moderately bitter ale, and Troeg's Perpetual IPA Imperial Pale Ale, as the strongly bitter ale.
A significant interaction between sensation seeking and quinine bitterness was found for the liking ratio of the imperial pale ale, Higgins pointed out. But the relationship was not straightforward.
"The interaction revealed liking of the pale ale increased with sensation seeking but only if quinine bitterness was also high," she said. "Intake models showed increased odds of frequent pale-ale intake with greater quinine bitterness and lower liking for lager beer. These data suggest liking and intake of pale ales is positively related to sensation seeking and bitter taste perception."
The findings, recently published in Food Quality and Preference, suggest that further research on the relationship between personality traits and the liking and intake of bitter foods and beverages may lead to new strategies to promote consumption of healthy bitter foods, Higgins contended.
"Avoidance of bitter foods can impact health negatively, because bitter foods such as cruciferous vegetables, green tea and grapefruit contain healthy compounds like flavonols, which are reported to have antioxidant and anticarcinogenic properties," she said.
The news about remdesivir, the investigational anti-viral drug that has shown early promise in the fight against COVID-19, keeps getting better.
This week researchers at Vanderbilt University Medical Center (VUMC), the University of North Carolina at Chapel Hill and Gilead Sciences reported that remdesivir potently inhibited SARS-CoV-2, the virus which causes COVID-19, in human lung cell cultures and that it improved lung function in mice infected with the virus.
These preclinical findings help explain the clinical effect the drug has had in treating COVID-19 patients. Remdesivir has been given to patients hospitalized with COVID-19 on a compassionate use basis since late January and through clinical trials since February.
In April, a preliminary report from the multicenter Adaptive COVID-19 Treatment Trial (which included VUMC) suggested that patients who received the drug recovered more quickly.
"All of the results with remdesivir have been very encouraging, even more so than we would have hoped, but it is still investigational, so it was important to directly demonstrate its activity against SARS-CoV-2 in the lab and in an animal model of disease," said VUMC's Andrea Pruijssers, PhD.
Pruijssers, research assistant professor of Pediatrics at VUMC and lead antiviral scientist in the laboratory of Mark Denison, MD, is the paper's co-corresponding author with Timothy Sheahan, PhD, assistant professor of Epidemiology at UNC-Chapel Hill.
Denison, the E.C. Stahlman Professor of Pediatrics at VUMC, directs the Division of Pediatric Infectious Diseases. He and Ralph Baric, PhD, the William R. Kenan, Jr. Distinguished Professor of Epidemiology at UNC-Chapel Hill, and colleagues have been studying remdesivir since 2014.
They were the first to perform detailed studies to demonstrate that the drug, which was developed by Gilead Sciences to combat hepatitis C and respiratory syncytial virus, and later the Ebola virus, also showed broad and highly potent activity against coronaviruses in laboratory tests.
The current findings, reported this week in the journal Cell Reports, provide "the first rigorous demonstration of potent inhibition of SARS-CoV-2 in continuous and primary human lung cultures." The study is also the first to suggest that remdesivir can block the virus in a mouse model.
Ongoing clinical trials will determine precisely how much it benefits patients in different stages of COVID-19 disease.
Meanwhile in the laboratory, Pruijssers said, "We also are focusing on how to use remdesivir and other drugs in combinations to increase their effectiveness during COVID-19 and to be able to treat at different times of infection."
COVID-19, which to date has infected more then 12 million people and killed nearly 600,000 worldwide, is at least the third instance since 2003 in which a coronavirus originally transmitted from bats has caused serious illness in humans.
Thus there is an urgent need to identify and evaluate broadly efficacious and robust therapies that can limit and prevent coronavirus infections. "Broad-spectrum antiviral drugs, antibodies, and vaccines are needed to combat the current pandemic and those that will emerge in the future," the researchers said.
In addition to SARS-CoV-2, studies in the Denison and Baric labs have shown that remdesivir is effective against a vast array of coronaviruses, including other bat viruses that could emerge in the future in humans.
"We hope that will never happen, but just as we were working to characterize remdesivir over the past six years to be ready for a virus like SARS-CoV-2, we are working and investing now to prepare for any future coronavirus," Denison said. "We want remdesivir and other drugs to be useful both now and in the future."
Populations around the world are living longer lives than was the norm just a few decades ago, presenting governments with significant challenges in terms of caring for their growing elderly populations. According to a new study published in PLOS ONE, understanding how to assess who is elderly is a crucial first step for our understanding of population aging.
The UN's Profiles of Ageing 2019 provides people who study population aging with a choice of perspectives, namely a conventional potential support ratio (PSR) and a prospective potential support ratio (PPSR). The difference between the two is based on different threshold ages at which people are first seen as "old". In the PSR the threshold age is 65 years and is fixed independently of time or place, while in the PPSR, the threshold age is the age where remaining life expectancy is 15 years. The first is commonly known as the conventional old age threshold and the second as the prospective old age threshold. The conventional old age threshold is the most commonly used, but it has the disadvantage that it does not change over time and is the same for all countries regardless of their trajectories of aging. This is of course not the case, as today's 65 year-olds are very different from their counterparts half a century ago, and are also likely to be very different from what they will be like half a century in the future. People also age differently depending on where they live and across population subgroups.
In their study, the authors propose that the old age threshold should be determined using an equivalency criterion - in other words, people at the old age threshold should be roughly similar to one another in terms of relevant characteristics regardless of when and where they lived. Using historical data on five-year death rates (the proportion of people dying between ages x and x+5) at the old age threshold as an indicator of one aspect of health, the researchers assessed the extent to which the two approaches used by the UN are consistent with the equivalency criterion. The results indicate that the old age threshold based on a fixed remaining life expectancy is consistent with the equivalency criterion, while the old age threshold based on a fixed chronological age is not. Specifically, five-year death rates at the old age threshold based on a fixed chronological age strongly decline over time, while the one based on a fixed remaining life expectancy is almost constant.
This implies that if the equivalency criterion were not at least approximately adhered to, people with a particular five-year death rate in one country would be categorized as old, while people in another country with the same five-year death rate would not be. The study is based on previous research by the authors in which they developed measures of population aging adjusted for changes in remaining life expectancy - a so-called dynamic old age threshold - and provides additional arguments around why it would be beneficial to use such measures of aging. They highlight that when this dynamic old age threshold is used to study people in many countries over long periods of time, at that threshold, people have roughly the same health.
"We wanted to provide researchers with a solid argument around why measures of aging based on a fixed remaining life expectancy should be used and how similar groups of older people should be defined. We want people to understand that the use of an old age threshold based on a fixed chronological age does not produce groups of adults whose relevant characteristics are comparable across time and space. The equivalency criterion is effective in making that decision because it defines who is elderly in a consistent way based on characteristics relevant to the study of population aging," explains IIASA researcher and study author Warren Sanderson.
"The picture of population aging that emerges when measures consistent with the equivalency criterion are used are markedly different from those that result when the equivalency criterion is not adhered to. We recommend that measures of aging that do not adhere to the equivalency criterion should only be used in special circumstances where it is inconsequential," concludes study author Sergei Scherbov, a researcher in the IIASA World Population Program.
Research shows that adolescents who live in areas that have high levels of artificial light at night tend to get less sleep and are more likely to have a mood disorder relative to teens who live in areas with low levels of night-time light. The research was funded by the National Institute of Mental Health (NIMH), part of the National Institutes of Health, and is published in JAMA Psychiatry.
“These findings illustrate the importance of joint consideration of both broader environmental-level and individual-level exposures in mental health and sleep research,” says study author Diana Paksarian, Ph.D., a postdoctoral research fellow at NIMH.
Daily rhythms, including the circadian rhythms that drive our sleep-wake cycles, are thought to be important factors that contribute to physical and mental health. The presence of artificial light at night can disrupt these rhythms, altering the light-dark cycle that influences hormonal, cellular, and other biological processes. Researchers have investigated associations among indoor artificial light, daily rhythms, and mental health, but the impact of outdoor artificial light has received relatively little attention, especially in teens.
In this study, Paksarian, Kathleen Merikangas, Ph.D., senior investigator and chief of the Genetic Epidemiology Research Branchat NIMH, and coauthors examined data from a nationally representative sample of adolescents in the United States, which was collected from 2001 to 2004 as part of the National Comorbidity Survey Adolescent Supplement (NCS-A). The dataset included information about individual-level and neighborhood-level characteristics, mental health outcomes, and sleep patterns for a total of 10,123 teens, ages 13 to 18 years old.
As part of in-person interviews for the NCS-A, the adolescents completed a validated assessment to determine whether they met the diagnostic criteria for various mental disorders. The teens also answered questions about their sleep habits, reporting what time they usually went to bed and how many hours of sleep they usually got on weeknights and on weekends.
To gauge the teens’ exposure to outdoor artificial light at night, the researchers used satellite imagery data to calculate the average artificial light levels for each census block group in the U.S. As expected, levels of artificial light at night varied according to certain neighborhood-level factors, such as urbanicity, socioeconomic levels, and population density.
Importantly, teens who lived in areas with high levels of artificial light at night tended to report later weeknight bedtimes and shorter weeknight sleep duration. This association held even after the researchers accounted for various individual-level factors (such as age, sex, race/ethnicity, number of siblings, parental education) and neighborhood-level factors (such as county-level urbanicity and population density). The analyses showed that, on average, teens in areas with the highest levels of outdoor light went to bed about 29 minutes later and got 11 fewer minutes of sleep than did teens in areas with the lowest levels.
The data showed that greater levels of artificial light at night were also associated with increased likelihood of having a mood disorder or anxiety disorder. Specifically, teens who lived in areas with higher levels of artificial light at night were more likely to meet the diagnostic criteria for bipolar disorder or specific phobia.
According to Paksarian and coauthors, this association is noteworthy because disruptions to sleep and circadian rhythms is a well-documented feature of certain mental disorders, including bipolar disorder. The study findings point to disrupted sleep as a possible link between artificial nighttime light exposure and mental health outcomes, a link that should be tested in future prospective research.
The study findings also highlight social disparities in exposure to artificial light, indicating that teens who belong to racial/ethnic minority groups, who come from immigrant families, or who come from families with lower income are more likely to live in areas with high levels of outdoor light at night. To the extent that exposure to artificial light disrupts daily rhythms such as sleep patterns, it could serve as an added stressor for teens who are already at increased risk for health problems due to social disadvantage.
Future experimental studies that examine the effects of different properties of artificial light – such as brightness and spectral composition – could help researchers determine whether lighting-focused interventions are likely to benefit adolescent sleep and mental health.
“Although environmental light exposure is only one factor in a more complex network of influences on sleep and behavior, it is likely to be an important target for prevention and interventions in adolescent health,” says Merikangas.
Positive thinking has long been extolled as the route to happiness, but it might be time to ditch the self-help books after a new study shows that realists enjoy a greater sense of long-term wellbeing than optimists.
Researchers from the University of Bath and London School of Economics and Political Science (LSE) studied people's financial expectations in life and compared them to actual outcomes over an 18-year period. They found that when it comes to the happiness stakes, overestimating outcomes was associated with lower wellbeing than setting realistic expectations.
The findings point to the benefits of making decisions based on accurate, unbiased assessments. They bring in to question the 'power of positive thinking' which frames optimism as a self-fulfilling prophecy, whereby believing in success delivers it, along with immediate happiness generated by picturing a positive future.
Negative thinking should not replace positive thinking though. Pessimists also fared badly compared to realists, undermining the view that low expectations limit disappointment and present a route to contentment.
Their numbers are dwarfed though by the number of people - estimated to be 80 percent of the population - who can be classed as unrealistic optimists. These people tend to overestimate the likelihood that good things will happen and underestimate the possibility of bad things. High expectations set them up for large doses of destructive disappointment.
"Plans based on inaccurate beliefs make for poor decisions and are bound to deliver worse outcomes than would rational, realistic beliefs, leading to lower well-being for both optimists and pessimists. Particularly prone to this are decisions on employment, savings and any choice involving risk and uncertainty," explains Dr Chris Dawson, Associate Professor in Business Economics in Bath's School of Management.
"I think for many people, research that shows you don't have to spend your days striving to think positively might come as a relief. We see that being realistic about your future and making sound decisions based on evidence can bring a sense of well-being, without having to immerse yourself in relentless positivity."
The results could also be due to counteracting emotions, say the researchers. For optimists, disappointment may eventually overwhelm the anticipatory feelings of expecting the best, so happiness starts to fall. For pessimists, the constant dread of expecting the worst may overtake the positive emotions from doing better than expected.
In the context of the Covid-19 crisis the researchers highlight that optimists and pessimists alike make decisions based on biased expectations: not only can this lead to bad decision making but also a failure to undertake suitable precautions to potential threats.
"Optimists will see themselves as less susceptible to the risk of Covid-19 than others and are therefore less likely to take appropriate precautionary measures. Pessimists, on the other hand, may be tempted to never leave their houses or send their children to school again. Neither strategy seems like a suitable recipe for well-being. Realists take measured risks based on our scientific understanding of the disease," said co-author Professor David de Meza from LSE's Department of Management.
Published in the American journal Personality & Social Psychology Bulletin the, findings are based on analysis from the British Household Panel Survey - a major UK longitudinal survey - tracking 1,600 individuals annually over 18 years.
To investigate whether optimists, pessimists or realists have the highest long-term well-being the researchers measured self-reported life satisfaction and psychological distress. Alongside this, they measured participants' finances and their tendency to have over- or under-estimated them.
Study after study has shown that statins can prevent heart attacks, strokes and death in middle-aged adults. But in 28 major clinical trials of statins, only 2 percent of participants have been 75 years or older. This means that even though older adults are at greater risk of heart disease and death, there is scant data on whether statins should be prescribed for them. A new study led by investigators from Brigham and Women's Hospital and VA Boston Healthcare System leverages national data from the U.S. Veterans Health Administration Services and Centers for Medicare & Medicaid Services to shed new light on the role statins may play for older adults who have not yet experienced a heart attack, stroke or other cardiovascular event. In their retrospective analysis, the researchers found that the risk of dying from any cause was lower by 25 percent among veterans who were using statins compared to those who were not treated with statins. The risk of dying from a cardiovascular event, such as a heart attack or stroke, was lower by 20 percent. The team's results are published inJAMA.
"Based on these data, age is not a reason to not prescribe statins," said lead and corresponding author Ariela Orkaby, MD, MPH, a physician scientist at VA Boston Health Care System and in the Division of Aging at the Brigham . "Statins are commonly studied and prescribed for middle-aged adults but understudied in people over age 75. One of the most remarkable things about our results is that we found the benefit of statins held true regardless of whether a person was older or younger or had a condition such as dementia."
Orkaby and colleagues looked at data on veterans who used VA services between 2002 and 2012, were 75 years or older, and had not previously had a heart attack, stroke or other cardiovascular event. Of the more than 300,000 eligible veterans, the team identified more than 57,000 who began taking statins during this time. Using propensity scoring, the authors compared individuals who began taking statins to those who had the same likelihood of being prescribed a statin based on clinical characteristics but did not receive a prescription for the drug.
Overall, taking statins was significantly associated with lower risk of death from a cardiovascular event or death from any cause. And the benefits remained for veterans at advanced age, including those who were 90 years or older. Lower death rates extended to those with other conditions such as dementia -- individuals who have been excluded from previous studies. In secondary analyses, the team found that starting a statin was also significantly associated with a lower risk of cardiovascular events such as heart attacks and strokes. Orkaby notes that it was particularly intriguing to see a marked decline in rate of strokes among the study's black participants.
"There are many interesting leads to follow up on," said Orkaby, "but it's important to keep in mind that this is not a randomized, clinical trial. Instead, it's a retrospective analysis using real world data that helps us explore where the truth lies."
The study focused only on veterans, a predominantly white and male population, which may limit its generalizability, but the study's size made it possible to glean statistically meaningful information on underrepresented groups. During the study's timeframe, the most commonly prescribed statin was simvastatin, but currently, higher-dose and higher-intensity statins have become more frequently prescribed. While statins are generally well tolerated, many people report aches and pains as a side effect, which may lead some to stop taking the drug. The current study did not evaluate whether patients discontinued statin use.
Two randomized, clinical trials of statins among older adults are now underway with results from one of the studies expected later this year. Orkaby and colleagues plan to follow up on their study by exploring the effects of statin dosing and examining outcomes for sub-populations included in their analysis.
On a gram for gram basis, animal proteins are more effective than plant proteins in supporting the maintenance of skeletal muscle mass with advancing age, shows research presented this week at The Physiological Society's virtual early career conference Future Physiology 2020.
The number of vegans in the UK has quadrupled since 2006, meaning that there are around 600,000 vegans in Great Britain (1). While we know plant-based diets are beneficial for the environment, we don't actually know how healthy these diets are for keeping muscles strong in elderly people.
Scientists generally agree that the primary driver of muscle loss with age -- at least in healthy individuals -- is a reduction of muscle proteins being built from amino acids. These amino acids come from protein that we eat and are also formed when we exercise.
Oliver Witard of King's College London is presenting research at The Physiological Society's Future Physiology 2020 conference about soy and wheat proteins showing that a larger dose of these plant proteins is required to achieve a comparable response of building muscles.
Simply transitioning from an animal-based protein diet to a plant-based diet, without adjusting total protein intake, will likely to be detrimental to muscle health during ageing. A more balanced and less extreme approach to changing dietary behaviour, meaning eating both animal and plant-based proteins, is best.
Witard and his colleagues conducted carefully controlled laboratory studies in human volunteers that involve the ingestion of plant compared with animal-based protein sources. To test changes in participants' muscles, they use several techniques including stable isotope methodology, blood sampling, and skeletal muscle biopsies to see how quickly the muscles were building up from amino acids.
It's important to note that this research to date has only compared two plant-based protein sources, namely soy and wheat. The researchers in this field will be conducting further research on other promising plant proteins such as oat, quinoa and maize.
Commenting on the research, Oliver Witard said: "This research challenges the broad viewpoint that plant proteins don't help build muscles as much as animal protein by highlighting the potential of alternative plant-based protein sources to maintain the size and quality of ageing muscles."
Short, frequent walks in blue spaces--areas that prominently feature water, such as beaches, lakes, rivers or fountains--may have a positive effect on people's well-being and mood, according to a new study led by the Barcelona Institute for Global Health (ISGlobal), a centre supported by the "la Caixa" Foundation.
The study, conducted within the BlueHealth project and published in Environmental Research, used data on 59 adults. Over the course of one week, participants spent 20 minutes each day walking in a blue space. In a different week, they spent 20 minutes each day walking in an urban environment. During yet another week, they spent the same amount of time resting indoors. The blue space route was along a beach in Barcelona, while the urban route was along city streets. Before, during and after each activity, researchers measured the participants' blood pressure and heart rate and used questionnaires to assess their well-being and mood.
"We saw a significant improvement in the participants' well-being and mood immediately after they went for a walk in the blue space, compared with walking in an urban environment or resting," commented Mark Nieuwenhuijsen, Director of the Urban Planning, Environment and Health Initiative at ISGlobal and coordinator of the study. Specifically, after taking a short walk on the beach in Barcelona, participants reported improvements in their mood, vitality and mental health.
The authors did not identify any cardiovascular health benefits, although they believe this may be due to the design of the study. "We assessed the immediate effects of taking a short walk along a blue space," commented ISGlobal researcher Cristina Vert, lead author of the study. "Continuous, long-lasting exposure to these spaces might have positive effects on cardiovascular health that we were not able to observe in this study."
The Importance of the Environment on Health
"Our results show that the psychological benefits of physical activity vary according to the type of environment where it is carried out, and that blue spaces are better than urban spaces in this regard," commented Vert.
Numerous ISGlobal studies have identified health benefits associated with green spaces, including lower risk of obesity, better attention capacities in children and slower physical decline in older adults. The new study provides evidence showing that blue spaces are an environment favourable to mental health.
"According to the United Nations, 55% of the global population now lives in cities," explained Nieuwenhuijsen. "It is crucial to identify and enhance elements that improve our health--such as blue spaces--so that we can create healthier, more sustainable and more liveable cities."
For decades, people diagnosed with familial hypercholesterolemia have been instructed to minimize their consumption of saturated fats to lower cholesterol and reduce their risks of heart disease. But a new study published in the prestigious journal "BMJ Evidence-Based Medicine" found no evidence to support those claims.
Familial hypercholesterolemia is a genetic disorder that causes people to have cholesterol levels 2-4 times higher than the average person. Organizations, including the American Heart Association, have suggested they avoid eating food from animal sources, such as meat, eggs and cheese, and to avoid coconut oil. An international team of experts on heart disease and diet, including five cardiologists, reviewed dietary guidelines for people with familial hypercholesterolemia. They say they couldn't find any justification for health experts to recommend a low saturated fat diet.
"For the past 80 years, people with familial hypercholesterolemia have been told to lower their cholesterol with a low saturated fat diet," said lead author David Diamond, professor and heart disease researcher at the University of South Florida. "Our study showed that a more 'heart healthy' diet is one low in sugar, not saturated fat."
Diamond and his co-authors say following a low-carb diet is most effective for people at increased risk of heart disease, such as those who are overweight, hypertensive and diabetic. Their findings are consistent with another paper recently published in the "Journal of the American College of Cardiology," which provided strong evidence that food that raises blood sugar, such as bread, potatoes and sweets, should be minimized, rather than tropical oils and animal-based food.
New research published today in theJournal of Physiologyshows that 12 weeks of easy-to-administer passive stretching helps improve blood flow by making it easier for your arteries to dilate and decreasing their stiffness.
Passive stretching differs from active stretching in that the former involves an external force (another person or gravity) stretching you, whereas active stretching is performed on your own. The changes they observed in blood vessels could have implications for diseases, including the number one global killer, heart disease.
Researchers at the University of Milan assigned 39 healthy participants of both sexes to two groups. The control group didn't undergo any stretching. The experimental group performed leg stretches 5 times a week for 12 weeks. Researchers evaluated the effect of passive stretching on the blood flow locally and in the upper arm. They found that the arteries in both the lower leg and upper arm had increased blood flow and dilation when stimulated, along with decreased stiffness.
Both of these changes may have implications for diseases such as heart disease, stroke and diabetes as they are characterized by changes in blood flow control, due to an impaired vascular system.
If this study is replicated in patients with vascular disease, it could indicate whether or not this training method could serve as a new drug-free treatment for improving vascular health and reducing disease risk, especially in people with lower mobility.
Moreover, stretching may also be used during hospitalisation or after surgical interventions, in order to preserve the vascular health when patients have low mobility. It can be also performed at home by carers or family members.
Emiliano Ce, an author on the paper said:
This new application of stretching is especially relevant in the current pandemic period of increased confinement to our homes, where the possibility of performing beneficial training to improve and prevent heart disease, stroke and other conditions is limited.
Exercise can slow or prevent the development of macular degeneration and may benefit other common causes of vision loss, such as glaucoma and diabetic retinopathy, new research suggests.
The new study from the University of Virginia School of Medicine found that exercise reduced the harmful overgrowth of blood vessels in the eyes of lab mice by up to 45%. This tangle of blood vessels is a key contributor to macular degeneration and several other eye diseases.
The study represents the first experimental evidence showing that exercise can reduce the severity of macular degeneration, a leading cause of vision loss, the scientists report. Ten million Americans are estimated to have the condition.
"There has long been a question about whether maintaining a healthy lifestyle can delay or prevent the development of macular degeneration. The way that question has historically been answered has been by taking surveys of people, asking them what they are eating and how much exercise they are performing," said researcher Bradley Gelfand, PhD, of UVA's Center for Advanced Vision Science. "That is basically the most sophisticated study that has been done. The problem with that is that people are notoriously bad self-reporters ... and that can lead to conclusions that may or not be true. This [study] offers hard evidence from the lab for very first time."
The Benefits of Exercise
Enticingly, the research found that the bar for receiving the benefits from exercise was relatively low - more exercise didn't mean more benefit. "Mice are kind of like people in that they will do a spectrum of exercise. As long as they had a wheel and ran on it, there was a benefit," Gelfand said. "The benefit that they obtained is saturated at low levels of exercise."
An initial test comparing mice that voluntarily exercised versus those that did not found that exercise reduced the blood vessel overgrowth by 45%. A second test, to confirm the findings, found a reduction of 32%.
The scientists aren't certain exactly how exercise is preventing the blood vessel overgrowth. There could be a variety of factors at play, they say, including increased blood flow to the eyes.
Gelfand, of UVA's Department of Ophthalmology and Department of Biomedical Engineering, noted that the onset of vision loss is often associated with a decrease in exercise. "It is fairly well known that as people's eyes and vision deteriorate, their tendency to engage in physical activity also goes down," he said. "It can be a challenging thing to study in older people. ... How much of that is one causing the other?"
The researchers already have submitted grant proposals in hopes of obtaining funding to pursue their findings further.
"The next step is to look at how and why this happens, and to see if we can develop a pill or method that will give you the benefits of exercise without having to exercise," Gelfand said. "We're talking about a fairly elderly population [of people with macular degeneration], many of whom may not be capable of conducting the type of exercise regimen that may be required to see some kind of benefit." (He urged people to consult their doctors before beginning any aggressive exercise program.)
Gelfand, a self-described couch potato, disclosed a secret motivation for the research: "One reason I wanted to do this study was sort of selfish. I was hoping to find some reason not to exercise," he joked. "It turned out exercise really is good for you."
A compound produced in the gut when we eat red meat damages our arteries and may play a key role in boosting risk of heart disease as we get older, according to new University of Colorado Boulder research.
The study, published this month in the American Heart Association journal Hypertension, also suggests that people may be able to prevent or even reverse such age-related decline via dietary changes and targeted therapies, like novel nutritional supplements.
"Our work shows for the first time that not only is this compound directly impairing artery function, it may also help explain the damage to the cardiovascular system that naturally occurs with age," said first author Vienna Brunt, a postdoctoral researcher in the Department of Integrative Physiology.
Eat a slab of steak or a plate of scrambled eggs, and your resident gut bacteria get to work immediately to break it down. As they metabolize the amino acids L-carnitine and choline, they churn out a metabolic byproduct called trimethylamine, which the liver converts to trimethylamine-N-Oxide (TMAO) and sends coursing through your bloodstream.
Previous studies have shown that people with higher blood levels of TMAO are more than twice as likely to have a heart attack or stroke and tend to die earlier.
But to date, scientists haven't completely understood why.
Drawing on animal and human experiments, Brunt and her team set out to answer three questions: Does TMAO somehow damage our vascular system? If so, how? And could it be one reason why cardiovascular health gets worse--even among people who exercise and don't smoke--as we get older?
The researchers measured the blood and arterial health of 101 older adults and 22 young adults and found that TMAO levels significantly rise with age. (This falls in line with a previous study in mice, showing the gut microbiome--or your collection of intestinal bacteria--changes with age, breeding more bacteria that help produce TMAO).
Adults with higher blood levels of TMAO had significantly worse artery function, the new study found, and showed greater signs of oxidative stress, or tissue damage, in the lining of their blood vessels.
When the researchers fed TMAO directly to young mice, their blood vessels swiftly aged.
"Just putting it in their diet made them look like old mice," said Brunt. She noted that 12-month-old mice (the equivalent of humans about 35 years old) looked more like 27-month-old mice (age 80 in people) after eating TMAO for several months.
Preliminary data also show that mice with higher levels of TMAO exhibit decreases in learning and memory, suggesting the compound could also play a role in age-related cognitive decline.
On the flip side, old mice that ate a compound called dimethyl butanol, (found in trace amounts in olive oil, vinegar and red wine) saw their vascular dysfunction reverse. Scientists believe that this compound prevents the production of TMAO.
Brunt notes that everyone--even a young vegan--produces some TMAO. But over time, eating a lot of animal products may take a toll.
"The more red meat you eat, the more you are feeding those bacteria that produce it," she said.
Senior author Doug Seals, director of the Integrative Physiology of Aging Laboratory, said the study is an important breakthrough because it sheds light on why our arteries erode with age, even in the healthiest people.
"Aging is the single greatest risk factor for cardiovascular disease, primarily as a result of oxidative stress to our arteries," said Seals. "But what causes oxidative stress to develop in our arteries as we age? That has been the big unkown. This study identifies what could be a very important driver."
The research team is now further exploring compounds that might block production of TMAO to prevent age-related vascular decline.
For now, they said, a plant-based diet may also keep levels in check.