People spend 1/6th of their lifetime on enhancing their appearance

And not only to find the love of their life!

Peer-Reviewed Publication

NATIONAL RESEARCH UNIVERSITY HIGHER SCHOOL OF ECONOMICS

An international team including HSE researchers has conducted the largest ever cross-cultural study of appearance-enhancing behaviours. They have found that people worldwide spend an average of four hours a day on enhancing their beauty. Caring for one's appearance does not depend on gender, and older people worry as much about looking their best as the young do. The strongest predictor of attractiveness-enhancing behaviours appears to be social media usage. The study findings have been published in Evolution and Human Behaviour.

People have always valued beauty. Throughout history, we have gone to great lengths to enhance our physical appearance. Early homo sapiens are known to have applied pigment to decorate their bodies, and ancient civilizations widely used cosmetics, ornate clothing, and jewellery. According to some scholars, our tendency for appearance enhancement might have originated from primate self-grooming behaviours.

But what exactly motivates us to spend time trying to look more physically attractive? From an evolutionary perspective, this may be part of mating behaviour, since good looks indicate good health and good genetics, maximising the chances of having healthy offspring; therefore, physical appearance is one of the key criteria in selecting a mate. From this perspective, women are assumed to be more interested in enhancing their physical attractiveness than men, and younger unmarried women are thought to be particularly concerned with their appearance.

There are a few other theories explaining people’s preoccupation with their physical attractiveness. One of them, the pathogen prevalence theory, suggests that people in countries with a high prevalence of dangerous infections such as leishmaniasis, trypanosomiasis, malaria, and leprosy are likely to spend more time improving their appearance, in particular to conceal visual imperfections which may be perceived as signs of disease. Sociocultural characteristics, such as gender inequality or individualistic vs. collectivist attitudes, and the influence of mass media or social media usage can also impact on how much time people invest in their appearance.

An international team of scientists including HSE researchers have tested the a range of these theories to determine which factors have the greatest impact on beauty-enhancing behaviour. The authors surveyed more than 93,000 people across 93 countries about the amount of time they spend every day enhancing their physical appearance. To date, it is the largest study carried out in in evolutionary psychology.

"We were able to collect data on almost 100,000 people across a very large sample in terms of age, education and income level, including many participants from non-industrial countries for which we had no previous data" Dmitrii Dubrov, Study co-author, Research Fellow of the HSE Centre for Sociocultural Research.

According to the evolutionary hypothesis, people want to look good to improve their chances of finding a suitable mate. The survey found both men and women spend an average of about four hours a day on behaviours designed to enhance their physical attractiveness. In addition to putting on makeup, grooming their hair grooming and selecting clothes, such behaviours include caring for body hygiene, exercising or following a specific diet for the purpose of improving one’s appearance (as opposed to taking care of one’s health, for example).

It has also been found that older people spend about as much time as younger ones enhancing their attractiveness. People in early romantic relationships tend to spend more time enhancing their appearance compared to those who are married or have been dating for a while.

The pathogen prevalence hypothesis was only partly confirmed: individuals with a history of serious pathogenic diseases were likely to spend more time enhancing their appearance, e.g. by applying makeup to mask traces of the disease, but no association was found between one's investment in beauty and living in a country where certain pathogens occur. The reason may be better healthcare, even in poorer countries which used to struggle with severe infections in the past.

As expected, women from countries with pronounced gender inequality tend to invest more time and effort in beauty enhancement than women in countries which have advanced gender equality. The same is true of countries and cultures with traditional attitudes towards gender roles.

Individualistic cultures that value individual accomplishments over those of the collective also emphasise the importance of enhancing one's physical attractiveness.

Social media usage appears to be the strongest predictor of attractiveness-enhancing behaviours. Active social media users – in particular, those who strive for unrealistic beauty standards and become concerned when their pictures get fewer likes – have been found to invest more time in improving their appearance than those who spend less or no time on social networks.

"In this paper, we tested five existing theories that shed light on people's attractiveness-enhancing behaviours. These theories are complementary rather than mutually exclusive. We confirmed certain assumptions and came up with some interesting and less expected results. This study is an important step in evolutionary and sociocultural research that will allow a better understanding of human psychology and our attitudes towards beauty", Dmitrii Dubrov, Study co-author, Research Fellow of the HSE Centre for Sociocultural Research. 

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JOURNAL

Evolution and Human Behavior

DOI

10.1016/j.evolhumbehav.2022.08.003 

ARTICLE TITLE

Predictors of enhancing human physical attractiveness: Data from 93 countries

Centuries of whaling data highlight likely climate change effect

Centuries-old whaling records show how southern right whales, or Tohorā, are altering their feeding habits.

Peer-Reviewed Publication

UNIVERSITY OF AUCKLAND

Southern right whales adjusted their foraging grounds over the past 30 years as climate change altered where prey could be found, according to a University of Auckland, Waipapa Taumata Rau scientist.

Dr Emma Carroll, of the School of Biological Sciences, was senior author of a paper which used data gleaned from contemporary whale skin samples along with whaling records stretching back to 1792. Over the past three decades, the whales increased their use of mid-latitude foraging grounds in the south Atlantic and southwest Indian oceans in the late summer and autumn, according to Carroll and dozens of collaborators including lead author Solène Derville, of Oregon State University.

The whales also slightly increased their use of high latitude foraging grounds in the southwest Pacific, according to the article, published in the journal PNAS. Southern right whales, or Tohorā, live south of the equator, eating krill and copepods, which are small crustaceans. Chemical analysis of skin samples revealed the whales’ feeding patterns in recent decades. The main source of historic data was the American whaling fleet's detailed records of where and what species were observed and killed in the Southern Hemisphere from the 18th to the early 20th century.

The whales' history and efforts to support Aotearoa's population are detailed on the website Tohorā Voyages. 

Tohorā were hunted to near extinction, with global numbers falling to as low as 500. By 2009, an estimated 2,200 of the creatures were in New Zealand waters, moving between the sub-Antarctic Auckland Islands (Maungahuka) and Campbell Island (Motu Ihupuku), and occasionally around mainland New Zealand including Stewart Island (Rakiura).

Southern right whales live from about 30 degrees South to more than 60 degrees South, the edge of the Antarctic. Large and slow-moving, the whales are mostly black in colour and easily identified by white growths on their heads called callosities. They have no dorsal fin and a V-shaped blowhole spray.

JOURNAL

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2214035120 

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Long-term stability in the circumpolar foraging range of a Southern Ocean predator between the eras of whaling and rapid climate change

Mysterious new behavior seen in whales may be recorded in ancient manuscripts

Feeding strategy recently discovered in whales may explain strange creatures described in Classical and Norse eras.

Peer-Reviewed Publication

FLINDERS UNIVERSITY

 

IMAGE: COD. 318FOL. 15V: HTTPS://WWW.E-CODICES.UNIFR.CH/EN/LIST/ONE/BBB/0318 CC BY 4.0, COLOR AND CONTRAST CORRECTED). view more 

CREDIT: COD. 318FOL. 15V: HTTPS://WWW.E-CODICES.UNIFR.CH/EN/LIST/ONE/BBB/0318 CC BY 4.0, COLOR AND CONTRAST CORRECTED).

In 2011, scientists recorded a previously unknown feeding strategy in whales around the world. Now, researchers in Australia think they may have found evidence of this behaviour being described in ancient accounts of sea creatures, recorded more than 2,000 years ago.

They believe that misunderstandings of these descriptions contributed to myths about medieval sea monsters.

Whales are known lunge at their prey when feeding, but recently whales have been spotted at the surface of the water with their jaws open at right angles, waiting for shoals of fish to swim into their mouths. A clip of this strategy was captured in 2021 and went viral on Instagram.

This strategy seems to work for the whales because the fish think they have found a place to shelter from predators, not realising they are swimming into danger.

It’s not known why this strategy has only recently been identified, but scientists speculate that it’s a result of changing environmental conditions - or that whales are being more closely monitored than ever before by drones and other modern technologies.

Dr John McCarthy, a maritime archaeologist in the College of Humanities, Arts and Social Sciences at Flinders University, first noticed intriguing parallels between marine biology and historical literature while reading about Norse sea monsters.

“It struck me that the Norse description of the hafgufa was very similar to the behaviour shown in videos of trap feeding whales, but I thought it was just an interesting coincidence at first. Once I started looking into it in detail and discussing it with colleagues who specialise in medieval literature, we realised that the oldest versions of these myths do not describe sea monsters at all, but are explicit in describing a type of whale, says Dr McCarthy.

“That’s when we started to get really interested. The more we investigated it, the more interesting the connections became and the marine biologists we spoke to found the idea fascinating.

Old Norse manuscripts describing the creature date from the 13th century and name the creature as a ‘hafgufa’.

This creature remained part of Icelandic myths until the 18th century, often included in accounts alongside the more infamous kraken and mermaids.

However, it appears the Norse manuscripts may have drawn on medieval bestiaries, a popular type of text in the medieval period. Bestiaries describe large numbers of real and fantastical animals and often include a description of a creature very similar to the hafgufa, usually named as the ‘aspidochelone’.

Both the hafgufa and aspidochelone are sometimes said to emit a special perfume or scent that helps to draw the fish towards their stationary mouths. Although some whales produce ambergris, which is an ingredient of perfume, this is not true of such rorquals as the humpback.

Instead, researchers suggest this element may have been inspired by the ejection of filtered prey by whales, to help attract more prey into a whale’s mouth.

Research co-author Dr Erin Sebo, an Associate Professor in Medieval Literature and Language in the College of Humanities, Arts and Social Sciences at Flinders University, says this may be another example of accurate knowledge about the natural environment preserved in forms that pre-date modern science.

“It’s exciting because the question of how long whales have used this technique is key to understanding a range of behavioural and even evolutionary questions. Marine biologists had assumed there was no way of recovering this data but, using medieval manuscripts, we’ve been able to answer some of their questions.”

“We found that the more fantastical accounts of this sea monster were relatively recent, dating to the 17th and 18th centuries and there has been a lot of speculation amongst scientists about whether these accounts might have been provoked by natural phenomena, such as optical illusions or under water volcanoes. In fact, the behaviour described in medieval texts, which seemed so unlikely, is simply whale behaviour that we had not observed but medieval and ancient people had.” 

The new paper on ancient descriptions of whales is: McCarthy, J., Sebo, E. and Firth, M., 2023. Parallels for cetacean trap feeding and tread-water feeding in the historical record across two millennia. Marine Mammal Science, pp.1-12. Accessible in full at https://onlinelibrary.wiley.com/doi/10.1111/mms.13009

The original 2017 description of the tread-water feeding behaviour by whales in the Gulf of Thailand is: Iwata, T., Akamatsu, T., Thongsukdee, S., Cherdsukjai, P., Adulyanukosol, K. and Sato, K., 2017. Tread-water feeding of Bryde’s whales. Current Biology, 27(21), pp.R1154-R1155. https://www.sciencedirect.com/science/article/pii/S0960982217312435 

A digital reconstruction of a humpback whale trap feeding (J. McCarthy).

CREDIT

John McCarthy, Flinders University

Icelandic Physiologus (c.1200) depiction of the Apsido feeding 

(Reykjavík AM 673 a II 4to fol. 3v Public Domain, color and contrast corrected).

Above: Ortelius's 1658 map of Iceland showing various mythological sea creatures. Below, a detail of a sea creature labelled H, ‘the greatest of whales’ which could not chase fish but caught them through cunning 

(Public Domain, color and contrast corrected).

VIDEOS

Bryde's Whales engaging in tread-water feeding in the Gulf of Thailand 2 (video courtesy of Surachai Passada, Department of Marine and Coastal Resources)

Bryde's Whales engaging in tre [VIDEO] | EurekAlert! Science News Releases

Bryde's Whales engaging in tread-water feeding in the Gulf of Thailand Close Up

Bryde's Whales engaging in tre [VIDEO] | EurekAlert! Science News Releases

JOURNAL

Marine Mammal Science

DOI

10.1111/mms.13009 

METHOD OF RESEARCH

Case study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Parallels for cetacean trap feeding and tread-water feeding in the historical record across two millennia

ARTICLE PUBLICATION DATE

28-Feb-2023

School-based wellness initiative shown to reduce average student BMI

Researchers at MUSC’s Boeing Center for Children’s Wellness report in the Journal of School Health that participation in its school-based wellness initiative is associated with decline in average student BMI over time in a diverse array of schools

Peer-Reviewed Publication

MEDICAL UNIVERSITY OF SOUTH CAROLINA

 

IMAGE: PHYSICAL ACTIVITY OPPORTUNITIES LED BY PE TEACHER, “MR. C”. AT FLOWERTOWN ELEMENTARY SCHOOL IN SUMMERVILLE, SOUTH CAROLINA. view more 

CREDIT: MEDICAL UNIVERSITY OF SOUTH CAROLINA. PHOTOGRAPH COURTESY OF THE MUSC BOEING CENTER FOR CHILDREN'S WELLNESS.

Health impacts students’ ability to learn. Leaders at  MUSC’s Boeing Center for Children’s Wellness (MUSC BCCW) believe that lessons on healthy living can be part of every student’s school experience.

“Healthier students are better learners, and better learners actually live healthier adult lives,” said Kathleen Head, M.D., MUSC BCCW associate medical director.

In a recent study published in the Journal of School Health, a research team led by Head and BCCW director Janice Key, M.D., compared the average student body mass index (BMI) in schools both participating and not participating in the MUSC BCCW School-based Wellness Initiative. The team used BMI data from the SC FitnessGram project, a statewide program to collect and track student health and fitness data in public schools.

Schools participating in the initiative saw their average student BMIs decrease significantly over time, regardless of school type. The average student BMI in the schools that used more wellness tools and programs was up to 15% lower than the schools that used fewer.

Implementing the School-based Wellness Initiative

Between 2014 and 2018, 103 South Carolina schools across five counties participated in  the School-based Wellness Initiative. The program targets policy, systems and environmental (PSE) change, such as schoolwide gardening projects or classwide stress reduction strategies, instead of solely individual changes.

To achieve this, the initiative uses the School Wellness Checklist (SWC). The SWC features seven categories of evidence-based strategies that schools can use to promote a culture of wellness  that includes getting started, nutrition, physical activity, social-emotional wellness, wellness culture, staff wellness and sustainability. Schools can choose which SWC items work best for them, and they are assigned points based on how many they use. One goal of the study is to determine which of these seven categories is most associated with average student BMI decreases.

Designing a wellness plan for a school using the SWC is a community effort. Head said that each school’s Wellness Committee designs a wellness plan specific to that school’s needs, explaining that the committee includes teachers, staff, administrators and parents, as well as community members, some of whom may have children at the school or just live in the area and are invested in advocacy.

She emphasized that the school-based nature of the initiative is particularly important. “The environment surrounding us as humans is critically important to our overall wellness,” she explained. “Children spend the majority of their day, five days per week, in school, eating, learning and playing.”

Bringing the initiative to schools also ensures program equity, as school-based programs reach all children regardless of medical access. “We want to reach all children and provide more than we can at a doctor visit,” said Key. “The BCCW must go where children are, which is school.”

Defining wellness in childhood

Over the past 40 years, childhood obesity rates have gone up 240%. Obesity is the state of having a BMI greater than 30, and the term overweight applies to those with BMIs between 25 and 30. This category changed in 1998 from a BMI between 27 and 30, shifting 25 million Americans from the normal weight to the overweight category.

About one third of the students in the study had a BMI in the obese or overweight category. Because children are still growing, their weights cannot be measured against preset ranges. Instead, pediatric BMIs are grouped together based on age and sex. Children in the 85th to 95th percentile of their group are considered overweight, and those above the 95th percentile are considered obese.

Though having an overweight or obese BMI is not a one-to-one guarantee of a negative health outcome, Head said that children who are categorized as obese are four times more likely to be diagnosed with diabetes by the time they’re age 25.

Key expressed that there are instances in which the BMI does not give an accurate picture of a child’s body composition, such as in an athletic student who may carry above average muscle mass.

“For something that is simple and easy to check for a whole classroom of kids, height and weight is the best we’ve got,” she said. “But when you’re looking at an individual patient, you would go beyond that.”

Building equitable and effective systems of wellness

Average BMIs went down in schools that participated in the initiative and went up in schools that did not. Additionally, in schools that participated for two years or more, a higher SWC score was associated with greater BMI decreases. Students in schools that scored 250 SWC points were 15% less likely to have overweight or obese BMIs than students in schools that earned only 50 SWC points.

Just as importantly, however, results were spread evenly across schools, Head explained.

“Our results were the same regardless of if the school was elementary, middle or high school, or if it was rural or urban, or if it was a Title I school or a non-Title I school,” she said.

Past school wellness programs have failed to deliver health benefits across different types of schools.

Though physical activity had the largest association with decreased BMI, followed by social-emotional wellness and staff wellness, nutrition education did not. “The disappointment to us was that decreased BMI wasn't associated with the score of nutrition interventions,” Key said.

She explained that this may be because students can actively practice physical activity and social-emotional wellness at school. However, food choice does not happen in the same way. Most food choices and options for students, such as nightly dinners, happen outside of the school and the wellness initiative.

Despite such challenges, Key said that they will not give up on nutrition.

Team members also want to diversify the data they track to monitor the effectiveness of their program. “In the future,” Head explained, “we’d like to measure knowledge, attitudes and behaviors associated with some of our interventions rather than skipping straight to BMI.

 

# # #

 

About MUSC

Founded in 1824 in Charleston, MUSC is the state’s only comprehensive academic health system, with a unique mission to preserve and optimize human life in South Carolina through education, research and patient care. Each year, MUSC educates more than 3,000 students in six colleges – Dental Medicine, Graduate Studies, Health Professions, Medicine, Nursing and Pharmacy – and trains more than 850 residents and fellows in its health system. MUSC brought in more than $297.8 million in research funds in fiscal year 2022, leading the state overall in research funding. For information on academic programs, visit musc.edu.

As the health care system of the Medical University of South Carolina, MUSC Health is dedicated to delivering the highest quality and safest patient care while educating and training generations of outstanding health care providers and leaders to serve the people of South Carolina and beyond. Patient care is provided at 14 hospitals with approximately 2,500 beds and five additional hospital locations in development, more than 350 telehealth sites and connectivity to patients’ homes, and nearly 750 care locations situated in all regions of South Carolina. In 2022, for the eighth consecutive year, U.S. News & World Report named MUSC Health the No. 1 hospital in South Carolina. To learn more about clinical patient services, visit muschealth.org.

MUSC and its affiliates have collective annual budgets of $5.1 billion. The nearly 25,000 MUSC team members include world-class faculty, physicians, specialty providers, scientists, students, affiliates and care team members who deliver groundbreaking education, research and patient care.

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JOURNAL

Journal of School Health

DOI

10.1111/josh.13292 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

Wastewater sector emits nearly twice as much methane as previously thought

Peer-Reviewed Publication

PRINCETON UNIVERSITY, ENGINEERING SCHOOL

 

IMAGE: RESEARCHERS STAND WITH THE PRINCETON CHEMISTRY EXPERIMENT MOBILE LABORATORY view more 

CREDIT: BUMPER DEJESUS / PRINCETON UNIVERSITY

Municipal wastewater treatment plants emit nearly double the amount of methane into the atmosphere than scientists previously believed, according to new research from Princeton University. And since methane warms the planet over 80 times more powerfully than carbon dioxide over 20 years, that could be a big problem.

“The waste sector is one of the largest anthropogenic sources of methane in the world,” said Mark Zondlo, professor of civil and environmental engineering and associated faculty at the Andlinger Center for Energy and the Environment. “As cities continue to urbanize and develop net-zero plans, they can’t ignore the liquid wastewater treatment sector.”

Zondlo led one of two new studies on the subject, both reported in papers published in Environmental Science & Technology. One study performed on-the-ground methane emissions measurements at 63 wastewater treatment plants in the United States; the other used machine learning methods to analyze published literature data from methane monitoring studies of various wastewater collection and treatment processes around the globe.

“Not many people have studied the methane emissions associated with wastewater infrastructure, even though we know that it’s a hotspot for methane production,” said Z. Jason Ren, who led the second study. Ren is a professor of civil and environmental engineering and the Andlinger Center for Energy and the Environment.

The Intergovernmental Panel on Climate Change (IPCC) has established guidelines that allow researchers and institutions like the U.S. Environmental Protection Agency (EPA) to estimate methane emissions from wastewater treatment plants based on their specific treatment processes. However, those guidelines were developed from limited measurements at a relatively small number of wastewater treatment plants.

And when the researchers used the Princeton Atmospheric Chemistry Experiment (PACE) Mobile Laboratory to quantify plant-wide emissions by measuring the plumes of 63 treatment plants on the east coast and in California, they found that the IPCC guidelines consistently underestimated treatment plants of all sizes and treatment processes.

If the results from those 63 plants are representative, actual methane emissions from wastewater treatment facilities across the U.S. would be about 1.9 times greater than emissions estimates that use existing IPCC and EPA guidelines, meaning that those guidelines underestimate methane emissions equivalent to 5.3 million metric tons of carbon dioxide.

Interestingly, the research team who performed the second independent study to analyze literature data on methane emissions came to a similar conclusion: estimated methane emissions from municipal wastewater treatment in the U.S. were around double of what existing guidelines would predict.

“We were able to show, using two different approaches, that methane emissions are a much bigger issue for the wastewater sector than previously thought,” Ren said.

The Princeton Chemistry Experiment Mobile Laboratory

CREDIT

Bumper DeJesus / Princeton University

The usual suspects in wastewater methane emissions

The researchers believe that since the IPCC guidelines were developed from limited measurements at a small number of wastewater treatment plants, they might not accurately represent the variation in emissions that exists between facilities.

“The guidelines assume a certain level of efficiency in these wastewater treatment systems that may not exist on a plant-to-plant basis,” said Daniel Moore, first author of the direct measurement study and a graduate student in civil and environmental engineering. He pointed to leaks and inefficient equipment that may go undetected at wastewater treatment plants but could lead to significant greenhouse gas emissions.

Cuihong Song, first author of the critical review and a postdoctoral researcher in civil and environmental engineering at Princeton, said that treatment plants equipped with anaerobic digesters were among the biggest methane leakers.

Anaerobic digesters are airtight vessels containing anaerobic microbes that work without oxygen to break down wastewater sludge or solid waste and produce methane-rich biogas in the process. That methane can be used to generate heat or electricity to power other aspects of the treatment process.

But when anaerobic digesters operate inefficiently, leaks and pressure buildups can allow methane to escape as fugitive emissions. “If the digester is not gas-tight, you can end up with high methane emissions,” Song said. The researchers found that plants with anaerobic digesters emitted more than three times the methane than plants without digesters.

Higher emissions from anaerobic digesters could be a serious problem: while wastewater treatment plants equipped with anaerobic digesters account for less than 10% of all treatment plants in the U.S., most of those plants are large facilities that, combined, treat around 55% of the wastewater in the country.

“A lot of money is going into decreasing emissions by implementing these digesters, because, in theory, they’re closed systems. When they’re working correctly, you can centralize the methane into one location,” Moore added. “It’s the inefficiencies and leakages that cause many of the problems.”

Along with anaerobic digesters, the critical review found that methane emissions from sewer systems contribute significantly to nationwide methane emissions. However, current guidelines largely do not account for fugitive methane emissions from sewers, which the researchers said are important to account for in future greenhouse gas inventories.

“We have more than a million miles of sewers in the U.S., filled with rich organic matter that may be causing methane emissions, but we have very little understanding of their scope,” Ren said.

Researcher Daniel Moore inspects the Princeton Chemistry Experiment Mobile Laboratory

CREDIT

Bumper DeJesus / Princeton University

Better monitoring, better guidelines

The researchers are now working with partners to build an inventory and methodology that would allow managers to easily monitor their methane emissions. By identifying the sources in the wastewater treatment process that release the most methane emissions, their work can also inform efforts to mitigate fugitive emissions.

“Methane has a short lifetime in the atmosphere, so if we’re able to cut off the spout of emissions across the country, methane’s contribution to warming will quickly diminish,” said Moore. “Ten years from now, we wouldn’t have to worry so much about methane.”

Ren added that the methane produced from processes like anaerobic digestion also serves as a valuable energy source. “By identifying and mitigating fugitive methane emissions, we would see double benefits,” he said. “We would reduce greenhouse gas emissions in the near term, and we would maximize the amount of methane we can recover from the wastewater treatment process.”

Still, more work is needed to monitor methane emissions at various timescales from treatment plants and sewer networks of different sizes and treatment processes.

For example, few studies have performed long-term, continuous monitoring of methane emissions from wastewater treatment plants, even though the emissions rate can vary daily or even seasonally, being generally higher in the spring and summer than in the winter. “Ultimately, we need to have a full accounting of the emissions from plants across many timescales,” Zondlo said. He added that preliminary analyses of subsequent measurements from additional plants at various times of the year have highlighted the importance of understanding seasonal variation in emissions.

At the same time, researchers will need to develop better sampling methods to understand emissions from hard-to-reach areas like sewers, since the diffuse nature of sewer networks along with their high humidity levels make it difficult to capture an accurate picture of emissions with existing methodologies.

By overcoming those hurdles and continuing their monitoring efforts, the researchers could contribute to a wider effort to create updated guidelines that better estimate methane emissions from the wastewater sector.

“Many agencies are recognizing that methane emissions from wastewater sector are important to study,” Ren said. “This research is not just reporting our own findings. We’re echoing what the broader research community has observed and identified as a significant gap of knowledge.”

The article, “Underestimation of sector-wide methane emissions from United States wastewater treatment,” with Daniel Moore as first author and Mark Zondlo as lead PI, was published in Environmental Science & Technology on Feb. 27. In addition to Moore and Zondlo, authors include Nathan Li, Lars Wendt, Mark Falinski, Jun-Jie Zhu, Cuihong Song, and Z. Jason Ren of Princeton; as well as Sierra Castañeda, a former Princeton student who is currently a Ph.D. student at Stanford University.

The article, “Methane Emissions from Municipal Wastewater Collection and Treatment Systems,” with Cuihong Song as first author and Z. Jason Ren as lead PI, was published in Environmental Science & Technology on Feb. 3. In addition to Song and Ren, authors include Jun-Jie Zhu, Daniel Moore, and Mark Zondlo of Princeton; as well as John Willis of Brown and Caldwell.

Support for the research projects was provided by the Energy and Environment Program at the Alfred P. Sloan Foundation (awarded alongside fellow project lead Francesca Hopkins of the University of California, Riverside), the High Meadow Environmental Institute via the Clear Water Challenge, and the Water Research Foundation via the Paul L. Busch Award.

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JOURNAL

Environmental Science & Technology

DOI

10.1021/acs.est.2c05373 

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Underestimation of Sector-Wide Methane Emissions from United States Wastewater Treatment

ARTICLE PUBLICATION DATE

27-Feb-2023

Plant-based low-carbohydrate diet linked with lower risk of premature death for people with type 2 diabetes

Peer-Reviewed Publication

HARVARD T.H. CHAN SCHOOL OF PUBLIC HEALTH

Key points:

• Adhering to a plant-based low-carbohydrate diet was associated with a reduction in overall, cardiovascular, and cancer mortality among people with type 2 diabetes
• Researchers observed the strongest health benefits among people who not only adhered to this diet but also had other healthy habits, such as exercising, not smoking, and consuming alcohol in moderate amounts

For immediate release: Tuesday, February 28, 2023

Boston, MA—Following a low-carbohydrate diet comprised primarily of plant-based foods was significantly associated with lower risk of premature death among people with type 2 diabetes, according to a new study led by researchers at Harvard T.H. Chan School of Public Health. It is the first prospective cohort study to examine the relationship between low-carbohydrate diet patterns and mortality among people with diagnosed type 2 diabetes.

“While avoiding refined and highly-processed carbohydrates has been widely recommended to lower the risk of developing type 2 diabetes, our study provides the first empirical evidence on how low-carb diets can help manage the progression of existing diabetes,” said lead author Yang Hu, research associate in the Department of Nutrition.

The study was published online February 14, 2023, and will appear in the April issue of Diabetes Care.

The researchers analyzed 34 years of health data from 7,224 women participating in the Nurses’ Health Study and 2,877 men participating in the Health Professionals Follow-up Study, all of whom developed type 2 diabetes after those studies began. The participants completed questionnaires on lifestyle and medical history every other year, allowing the researchers to assess the compositions of their diets and score them according to intake of animal proteins and fats, vegetable proteins and fats, high-quality carbohydrates, and low-quality carbohydrates.

The findings showed a 24% reduction in all-cause mortality among those adhering to a low-carbohydrate dietary pattern. The health benefits were stronger for low-carbohydrate diets that emphasized plant-based foods and high-quality carbohydrates, such as fruits, vegetables, and whole grains. Those diets were also associated with a lower cardiovascular disease and cancer mortality. Low-carbohydrate diets that emphasized animal products and low-quality carbohydrates, such as potatoes, added sugars, and refined grains, were not significantly associated with lower mortality.

The researchers observed the strongest health benefits among people adhering to other healthy habits, such as not smoking, regularly exercising, and drinking alcohol in moderation, alongside a plant-based low-carbohydrate diet.

“This study, once again, underscores the importance of diet quality when choosing among various diets for diabetes control and management,” said Qi Sun, senior author and associate professor in the Departments of Nutrition and Epidemiology.

Other Harvard Chan School co-authors included Edward Yu, JoAnn E. Manson, Eric B. Rimm, Liming Liang, Walter C. Willett, and Frank B. Hu.

Funding for the study—and for the Nurses’ Health Study and Health Professionals Follow-up study underpinning it—came from National Institutes of Health grants UM1 CA186107, P01 CA87969, R01 HL034594, U01 CA167552, R01 HL35464, R01 HL60712, R01 DK120870, R01 DK126698, R01 DK119268, U2C DK129670, DK119268, R01 ED022981, and R21 AG070375.

“Low-Carbohydrate Diet Scores and Mortality Among Adults With Incident Type 2 Diabetes,” Yang Hu, Gang Liu, Edward Yu, Biqi Wang, Clemens Wittenbecher, JoAnn E. Manson, Eric B. Rimm, Liming Liang, Kathryn Rexrode, Walter C. Willett, Frank B. Hu, Qi Sun, Diabetes Care, April 2023, doi: 10.2337/dc22-2310

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JOURNAL

Diabetes Care

DOI

10.2337/dc22-2310 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Low-Carbohydrate Diet Scores and Mortality Among Adults With Incident Type 2 Diabetes