People with Parkinson’s disease report that tremors worsen during stressful situations. ‘Tremors act as a sort of barometer for stress; you see this in all people with Parkinson’s’, says neurologist Rick Helmich from Radboud university medical center. The commonly used drug levodopa usually helps with tremors, but it tends to be less effective during stress, when tremors are often at their worst. Helmich and his team wanted to investigate whether a medication targeting the stress system could help and how this effect of stress on tremors works in the brain.

Mathematical calculations

The medication in question, propranolol, is a beta-blocker that inhibits the action of stress hormones. It was developed for high blood pressure and heart arrhythmias, has been around for a long time, and is already used as a standard treatment for essential tremor — a condition in which people experience tremors without other neurological symptoms. There were already indications that propranolol might reduce tremors in Parkinson’s, but until now, no thorough research has explored its potential effects.

Helmich and his team studied 27 people with Parkinson’s who experienced tremors. They were given propranolol on one day and a placebo on another day. A device on their hands measured the intensity of their tremors, while an MRI scan mapped brain activity. This was done both at rest and during a task involving stressful mathematical calculations. The stress response was measured by pupil size and heart rate, both of which increased during the calculations. As expected, without medication, tremors worsened during stress.

Amplifier

The study showed that propranolol reduced tremors both at rest and during stress. The MRI scans revealed how this works: after taking the medication, the brain circuit responsible for tremors showed less activity. Helmich explains: ‘We know that abnormalities in systems like the dopamine system cause tremors. Based on our study, we now think that the stress hormone noradrenaline acts as an amplifier, which increases tremor intensity in the brain’s movement area. Propranolol inhibits this amplifying effect and thus reduces symptoms.’

It surprised the researchers that propranolol also worked to reduce tremors at rest. ‘Apparently, our stress system is occasionally active, even at rest’, says researcher Anouk van der Heide. ‘This changes how alert someone is and leads to spontaneous fluctuations in tremors. We previously thought that the stress hormone system was only active under stress, but apparently, that’s too simplistic. It also plays a role at rest.’

Mindfulness

Helmich already prescribes propranolol for some Parkinson’s patients. ‘The most effective medication for Parkinson’s is levodopa. It not only helps with tremors but also with other symptoms, so that’s what we start with’, Helmich explains. ‘However, in about forty percent of patients, it is not effective against tremors. In that case, we first increase the dose, but if that doesn’t work, propranolol is an option. However, we must be cautious about side effects, such as low blood pressure.’

In addition to medication studies, Helmich’s team is also exploring lifestyle changes that could help with Parkinson’s. ‘It doesn’t take much to trigger a stress response, causing people to tremble more. Even something as simple as wondering: did I lock the front door? can set it off. We are currently investigating whether mindfulness can positively influence the stress system.’

Deep-sea temperature is stable, with only minor changes occurring even over long-time scales. Despite this stability, deep-sea organisms are highly adapted to such stable environments, making them particularly sensitive to even slight temperature fluctuations. Unlike surface water, the deep sea lacks primary production due to the absence of sunlight, which prevents phytoplankton growth and photosynthesis. Instead, deep-sea organisms rely on food that descends from the ocean surface, known as particulate organic material or marine snow. This includes dead plankton, a primary food source of organisms living on the deep ocean floor.

A new study conducted by the research team, utilising empirical data from deep-sea fossils extracted from sediment cores spanning 500,000 years, clearly demonstrated that temperature and food input have significantly modified deep-sea communities over long time scales, each affecting different species.

Professor Yasuhara stated, ‘It’s important not only to advance fundamental science by understanding how ecosystems on our planet operate but also to address the growing challenges posed by human-induced climatic change.’

As global concern over ongoing human-induced climatic warming and its future escalation intensifies, scientists and engineers are working hard to develop mitigation technologies to combat climatic change. These geoengineering technologies, collectively referred to as ocean-based climate intervention (OBCI), include approaches such as marine carbon dioxide removal (mCDR), which aim to reduce future warming by putting and storing carbon or carbon dioxide in deep-sea sediment, where they remain stable due to the low-temperature and high-pressure environments.

One prominent example of mCDR is iron fertilisation, a process in which iron is added to the ocean surface to enhance primary production, resulting in increased sinking of organic carbon to the deep-sea floor. While mCDR and OBCI are technologically advanced and nearly ready for implementation, they have yet to be deployed on large scales. One major concern is how these technologies will affect deep-sea ecosystems.

Yasuhara continues, ‘Deep sea covers over 40% of our planet’s surface, and its ecosystem is known to be highly vulnerable. The deep sea also harbours countless species that are still undiscovered. I would say the vast majority of species remain unknown to us. Our study, using a fossil record from a deep-sea sediment core for the past 500,000 years, shows that both temperature and food input, driven by changes in natural iron fertilisation through dust input and the resulting surface production enhancement, have altered deep-sea ecosystems in different ways substantially. This means we must be cautious when making decisions about this important and delicate ecosystem. Careful ecosystem impact assessments are needed to evaluate, on a case-by-case basis, whether human-induced warming or mCDR involving surface productivity changes is more harmful. Only then can we make a cautious and sensible decision about whether to proceed with mCDR.’

Professor Yasuhara also remarked that the Southern Ocean can be seen as a ‘canary in a coal mine’ because it’s a key sensitive region in the global ocean circulation and climatic system. ‘Our study highlights the sensitivity of its deep-sea ecosystem. Increased deep-sea biological monitoring efforts in this region are needed, as it could provide early warning signals of climatic changes. Our study also showed that the present-day style of the deep-sea ecosystem in the Southern Ocean was established 430,000 years ago. I hope such a long-standing ecosystem won’t be completely altered in the near future, especially since we don’t know how much this human-induced warming will escalate and fundamentally change our global climatic system in future.’

Over half of U.S. adults (52%) think the vaccine given to pregnant individuals to protect their infants from RSV (respiratory syncytial virus) is effective, up from 42% in October 2023, soon after the Centers for Disease Control and Prevention (CDC) recommended the vaccine. And 61% say the RSV vaccine for adults age 60 and older is effective, up from 54% in October 2023.

The rise in perceived effectiveness for the RSV vaccine comes even though there has been no sign to date of a dreaded “tripledemic,” the wave of flu, Covid-19, and RSV illnesses that filled emergency rooms in the fall and winter of 2022-23 and may have resulted in over 100,000 U.S. deaths. As of Dec. 20, 2024, the CDC reports overall moderate levels of acute respiratory illness, though flu season is underway with levels increasing across the country, Covid-19 activity is increasing from low levels in some areas of the country, and RSV activity is high and increasing in most U.S. areas, especially in young children.

The rise also comes as several of president-elect Donald Trump’s nominees for leading policy-making health positions have cast doubt on the efficacy and safety of vaccines, notably Health and Human Services Secretary nominee Robert F. Kennedy Jr., who has said “no vaccine” is safe and effective, and CDC chief nominee Dave Weldon, who, like Kennedy, has promoted the disproven link between vaccines and autism.

The APPC survey findings are based on a nationally representative panel survey of 1,771 U.S. adults fielded from Nov. 14-24, 2024, and has a margin of error of ± 3.3 percentage points. For more on the survey, see the end of this news release or the topline.

Vaccine hesitancy may have plateaued

The past several years have shown evidence of increased vaccine hesitancy. However, by several measures in the November survey, including the RSV findings noted above, public acceptance of vaccination has risen slightly or held steady:

• 86% of respondents say the measles, mumps, and rubella vaccine (MMR) is safe, up from 81% in October 2023. The rebound brings it back toward the 88% who perceived it as safe in August 2022.
• 83% say the flu vaccine is safe, unchanged from October 2023.
• 65% say the Covid-19 vaccine is safe, unchanged from last fall.
• The perceived effectiveness of a variety of other vaccines is unchanged from October 2023.
• Over three-quarters of the public would recommend various vaccines, when appropriate, to members of their families and households.

In addition, despite continuing attacks on the safety and efficacy of certain vaccines by some politicians, 9 in 10 respondents say it is important for parents to get their children vaccinated: 72% say it is very or extremely important and 19% say it is somewhat important. Only 10% say it is not at all or not very important that parents get their children vaccinated.

Flu vaccine vs. Covid-19

In the survey, U.S. adults view the seasonal flu shot as more effective at reducing the risk of getting a severe case of the flu this season (75%) than the Covid booster is at reducing the risk of getting a severe case of Covid this season (55%). There’s been a significant increase in understanding that the flu shot doesn’t necessarily prevent a person who is exposed to the flu from getting sick but it does make the infection less severe (54%, up from 48% in October 2023). Fewer people say they are unsure what effect a flu shot has on a person who is later exposed to someone with the flu (14%, down from 20%).

The November data show that fewer people have received or plan to receive the Covid booster, as compared with the flu shot:

• Just over half of survey respondents (51%) either got the seasonal flu shot (40%) or say they are very likely to (11%) get it, compared with 38% who either got the latest Covid-19 booster (29%) or say they are very likely to (9%).
• The most common reason people select to explain why they have received the Covid booster and the flu shot is to protect themselves against catching that illness (82% and 78%, respectively).
• More people report getting the flu shot because they “get it every year” (76%) than those who report getting the Covid booster because they “get one every time a new booster comes out” (51%).
• 68% know they can get a Covid booster and a flu shot in the same visit to a health care clinic or pharmacy, unchanged from October 2023, though there’s a significant increase in the number who report that this is definitely true (44%, up from 38% in October 2023).

Flu knowledge

• Most people (80%) know the effectiveness of the seasonal flu shot varies year to year.
• Although most people (69%) see this year’s flu vaccine as effective at reducing the risk of getting the flu (unchanged from October 2023), more people think it is ineffective this fall (20%) than last fall (15%).
  • In fact, early reports suggest that this seasonal flu vaccine may be less effective than last year’s: Based on reports from five South American countries, the CDC has said the effectiveness of the seasonal flu vaccine at cutting the risk of hospitalization among high-risk groups appears to be 35%, lower than the 51.9% seen in those countries last flu season, according to WebMD.
• 69% know that there is value in getting a flu shot after November, but 19% are unsure.
• Most people (80%) know it is possible to spread the flu to others even if you have no symptoms, up from 76% in January of 2023. (The CDC says that some “people can be infected with influenza viruses and have no symptoms but may still be able to spread the virus to their close contacts.”)
• Most (71%) know that the flu shot is the best defense against seasonal flu.
• However, only 42% believe that everyone 6 months of age and older should get a flu shot, unchanged from last year.

Beliefs in vaccine effectiveness and safety

Longstanding vaccines such as the MMR, polio, and Tdap (tetanus, diphtheria, and pertussis) vaccines are usually top-rated by the public in effectiveness, safety, and in recommendations that others get the vaccines. Newer vaccines such as the Covid-19 vaccine or those for which public health advice has recently changed — such as the CDC recommendation that adults 50 and older get a vaccine against pneumonia — are less familiar and often lower-rated by the public.

Recommending vaccines. Here are the public’s views on recommending vaccines to others:

• MMR vaccine: 90% would be likely to recommend an MMR vaccine for a child in their household who is either between the ages of 12-15 months or 4 to 6 years old.
• Polio vaccine: 88% would be likely to recommend a polio vaccine to a child in their household of 2 to 6 months old.
• Tdap vaccine: 85% would be likely to recommend a Tdap vaccine to a child in their household of 11-12 years old or an adult in their family.
• Shingles vaccine: 82% would be likely to recommend a shingles vaccine to someone age 50+ in their family.
• HPV vaccine: 79% would be likely to recommend an HPV (human papillomavirus) vaccine for a child aged 11 or 12 years old in their household.
• Pneumonia vaccine: 77% would be likely to recommend a pneumonia vaccine to a person aged 50 or older in their family, down from 84% who were likely to recommend it to someone 65 or older in their family in April 2022. The CDC recommended lowering the age for the vaccine on Oct. 23, 2024, weeks before this survey was fielded.

Vaccine safety. Public views on vaccine safety:

• MMR: 86% say the MMR vaccine is safe, up from 81% in October 2023 (as noted above)
• Flu: 83% say the flu vaccine is safe, unchanged
• Covid-19: 65% say the Covid-19 vaccine is safe, unchanged from October 2023 but lower than 73% in August 2022.

Vaccine effectiveness. Public views on vaccine effectiveness are stable with the exception of RSV, which rose as noted above. The following percentages saw these vaccines as effective. Comparisons are to October 2023, if this question was asked then:

• MMR: 86% see the vaccine as effective (unchanged)
• Polio: 85%
• Tdap: 80%
• Flu: 75% (unchanged)
• Shingles: 74% (unchanged)
• Pneumonia: 71% (unchanged)
• HPV: 65% (unchanged)
• Covid-19: 65% (unchanged)
• RSV for adults 60 and older: 61%, up from 54% in October 2023
• RSV for pregnant individuals: 52%, up from 42% in October 2023

APPC’s Annenberg Science and Public Health knowledge survey

The survey data come from the 22^nd wave of a nationally representative panel of 1,771 U.S. adults conducted for the Annenberg Public Policy Center by SSRS, an independent market research company. Most have been empaneled since April 2021. To account for attrition, small replenishment samples have been added over time using a random probability sampling design. The most recent replenishment, in September 2024, added 360 respondents to the sample. This wave of the Annenberg Science and Public Health Knowledge (ASAPH) survey was fielded Nov. 14-24, 2024. The margin of sampling error (MOE) is ± 3.3 percentage points at the 95% confidence level. All figures are rounded to the nearest whole number and may not add to 100%. Combined subcategories may not add to totals in the topline and text due to rounding.

KAIST (represented by President Kwang Hyung Lee) announced on the 20th of December that a research team led by Professor Kwang-Hyun Cho from the Department of Bio and Brain Engineering has developed a groundbreaking technology that can treat colon cancer by converting cancer cells into a state resembling normal colon cells without killing them, thus avoiding side effects.

The research team focused on the observation that during the oncogenesis process, normal cells regress along their differentiation trajectory. Building on this insight, they developed a technology to create a digital twin of the gene network associated with the differentiation trajectory of normal cells.

Through simulation analysis, the team systematically identified master molecular switches that induce normal cell differentiation. When these switches were applied to colon cancer cells, the cancer cells reverted to a normal-like state, a result confirmed through molecular and cellular experiments as well as animal studies.

This research demonstrates that cancer cell reversion can be systematically achieved by analyzing and utilizing the digital twin of the cancer cell gene network, rather than relying on serendipitous discoveries. The findings hold significant promise for developing reversible cancer therapies that can be applied to various types of cancer.

Professor Kwang-Hyun Cho remarked, “The fact that cancer cells can be converted back to normal cells is an astonishing phenomenon. This study proves that such reversion can be systematically induced.”

He further emphasized, “This research introduces the novel concept of reversible cancer therapy by reverting cancer cells to normal cells. It also develops foundational technology for identifying targets for cancer reversion through the systematic analysis of normal cell differentiation trajectories.”

The study was supported by the Ministry of Science and ICT and the National Research Foundation of Korea through the Mid-Career Researcher Program and Basic Research Laboratory Program. The research findings have been transferred to BioRevert Inc., where they will be used for the development of practical cancer reversion therapies.

Even if an android’s appearance is so realistic that it could be mistaken for a human in a photograph, watching it move in person can feel a bit unsettling. It can smile, frown, or display other various, familiar expressions, but finding a consistent emotional state behind those expressions can be difficult, leaving you unsure of what it is truly feeling and creating a sense of unease.

Until now, when allowing robots that can move many parts of their face, like androids, to display facial expressions for extended periods, a ‘patchwork method’ has been used. This method involves preparing multiple pre-arranged action scenarios to ensure that unnatural facial movements are excluded while switching between these scenarios as needed.

However, this poses practical challenges, such as preparing complex action scenarios beforehand, minimizing noticeable unnatural movements during transitions, and fine-tuning movements to subtly control the expressions conveyed.

In this study, lead author Hisashi Ishihara and his research group developed a dynamic facial expression synthesis technology using “waveform movements,” which represents various gestures that constitute facial movements, such as “breathing,” “blinking,” and “yawning,” as individual waves. These waves are propagated to the related facial areas and are overlaid to generate complex facial movements in real time. This method eliminates the need for the preparation of complex and diverse action data while also avoiding noticeable movement transitions.

Furthermore, by introducing “waveform modulation,” which adjusts the individual waveforms based on the robot’s internal state, changes in internal conditions, such as mood, can be instantly reflected as variations in facial movements.

“Advancing this research in dynamic facial expression synthesis will enable robots capable of complex facial movements to exhibit more lively expressions and convey mood changes that respond to their surrounding circumstances, including interactions with humans,” says senior author Koichi Osuka. “This could greatly enrich emotional communication between humans and robots.”

Ishihara adds, “Rather than creating superficial movements, further development of a system in which internal emotions are reflected in every detail of an android’s actions could lead to the creation of androids perceived as having a heart.”

By realizing the function to adaptively adjust and express emotions, this technology is expected to significantly enhance the value of communication robots, allowing them to exchange information with humans in a more natural, humanlike manner.

In the first large-scale paired camera trap and autonomous recording survey for large African carnivores, researchers were able to identify individual leopards by their vocalisations with 93% accuracy.

It has been hailed as an important first step towards using bioacoustics in the conservation of leopards.

Leopards are listed as ‘vulnerable’ to extinction according to the IUCN Red List of Threatened Species mainly due to habitat loss and human-wildlife conflict.

But because leopards are solitary, nocturnal creatures that live across huge expanses of terrain, scientists struggle to gather reliable data that would help them reverse population declines.

There is little scientific research about the ‘sawing roar’ of a leopard — a repeated low-frequency pattern of strokes, often audible from at least a kilometre away, used primarily to attract mates and for territorial defence.

But studying leopards through the sounds they make — a technique known as bioacoustics and more typically used to monitor birds and marine species — would have the advantage of allowing researchers to monitor much larger areas.

It could lead to more complex studies such as population estimates, a key metric for helping policymakers and conservation practitioners understand how to manage landscapes and mitigate human-wildlife conflicts.

The research team conducted their study across a 450km2 expanse of the Nyerere National Park in Tanzania, where they attached 50 pairs of cameras to trees along roads and trails.

They placed microphones next to each camera so that they could identify the leopard from the camera and then extract the roaring bouts from the audio.

They then used a modelling system to analyse the temporal pattern of a leopard’s roar, and found individual identification was possible, with an overall accuracy of 93.1%.

The study shows that using multiple forms of technology to record complementary data can exploit a wider variety of species traits than single technology studies alone.

Lead author Jonathan Growcott, a PhD student at the University of Exeter, said: “Discovering that leopards have unique roars is an important but fundamentally quite basic finding that shows how little we know about leopards, and large carnivores in general.

“We hope it will allow leopards to become the focus of more acoustically complex science such as population density studies and open the door to more work on how large carnivores use vocalisations as a tool.

“Importantly, our success in using a combination of different types of technology could hopefully lead others to think about how to integrate different types of technology into their research, as the rich data this provides could really push science ahead and help us understand ecosystems and landscapes in a much more holistic way.”

The research was a collaborative effort between the University of Exeter, the Wildlife Conservation Unit at the University of Oxford, Lion Landscapes, Frankfurt Zoological Society, TAWIRI (Tanzania Wildlife Institute for Research) and TANAPA (Tanzania National Parks Authority), as well as computer scientists from Exeter and Oxford.

It was presented by Growcott at the British Ecological Society Annual meeting in Liverpool earlier this month, an event which brought together 1,500 ecologists.

Hazel Norman, CEO of the British Ecological Society said: “This study showing that individual leopards can be identified and monitored just through their roars is a brilliant example of how ecologists are applying novel ideas and technologies to uncover fascinating new insights into our natural world.

“Jonathan presented this research at our recent British Ecological Society Annual Meeting in Liverpool, which is a brilliant forum for ecologists to share their research and ideas with the ecological community and beyond.”

Changes in these spin states can be detected using optically detected magnetic resonance (ODMR), which measures fluorescence changes under microwave radiation. NDs with NV centers are biocompatible and can be designed to interact with specific biological molecules, making them valuable tools for biological sensing. However, NDs used for bioimaging generally exhibit lower spin quality compared to bulk diamonds, resulting in reduced sensitivity and accuracy in measurements.

In a recent breakthrough, scientists from Okayama University in Japan developed nanodiamond sensors bright enough for bioimaging, with spin properties comparable to those of bulk diamonds. The study, published in ACS Nano, on 16 December 2024, was led by Research Professor Masazumi Fujiwara from Okayama University, in collaboration with Sumitomo Electric Company and the National Institutes for Quantum Science and Technology.

“This is the first demonstration of quantum-grade NDs with exceptionally high-quality spins, a long-awaited breakthrough in the field. These NDs possess properties that have been highly sought after for quantum biosensing and other advanced applications,” says Prof. Fujiwara.

Current ND sensors for bioimaging face two main limitations: high concentrations of spin impurities, which disrupt NV spin states, and surface spin noise, which destabilizes the spin states more rapidly. To overcome these challenges, the researchers focused on producing high-quality diamonds with very few impurities. They grew single-crystal diamonds enriched with 99.99% ¹²C carbon atoms and then introduced a controlled amount of nitrogen (30-60 parts per million) to create an NV center with about 1 part per million. The diamonds were crushed into NDs and suspended in water.

The resulting NDs had a mean size of 277 nanometers and contained 0.6-1.3 parts per million of negatively charged NV centers. They displayed strong fluorescence, achieving a photon count rate of 1500 kHz, making them suitable for bioimaging applications. These NDs also showed enhanced spin properties compared to commercially available larger NDs. They required 10-20 times less microwave power to achieve a 3% ODMR contrast, had reduced peak splitting, and demonstrated significantly longer spin relaxation times (T₁ = 0.68 ms, T₂ = 3.2 µs), which were 6 to 11 times longer than those of type-Ib NDs. These improvements indicate that the NDs possess stable quantum states, which can be accurately detected and measured with low microwave radiation, minimizing the risk of microwave-induced toxicity in cells.

To evaluate their potential for biological sensing, the researchers introduced NDs into HeLa cells and measured the spin properties using ODMR experiments. The NDs were bright enough for clear visibility and produced narrow, reliable spectra despite some impact from Brownian motion (random ND movement within cells). Furthermore, the NDs were capable of detecting small temperature changes. At temperatures around 300 K and 308 K, the NDs exhibited distinct oscillation frequencies, demonstrating a temperature sensitivity of 0.28 K/√Hz, superior to bare type-Ib NDs.

With these advanced sensing capabilities, the sensor has potential for diverse applications, from biological sensing of cells for early disease detection to monitoring battery health and enhancing thermal management and performance for energy-efficient electronic devices. “These advancements have the potential to transform healthcare, technology, and environmental management, improving quality of life and providing sustainable solutions for future challenges,” says Prof. Fujiwara.

The national survey found that discarded frozen items make up about 6% of wasted household food in the United States. Based on frozen food’s relatively small contribution to food waste and other findings in the study, researchers say urging consumers to stock their freezers might be one way to prevent premature disposal of food.

Results showed that though overall food waste remained high, there was a bright spot: Freezing food was associated with less food landing in the trash.

“We found that households with home freezing behaviors are more likely to have less food waste than other households,” said Lei Xu, first author of the paper and a postdoctoral scholar specializing in agricultural and food economics at The Ohio State University.

“Food waste is not just an economic loss — it also causes environmental damage because more than 90% of wasted food goes to the landfill, and this can produce greenhouse gas emissions,” Xu said. “The findings suggest that in the future, if we can encourage households to have home freezing behaviors, this small change in food storage habits can have a large environmental impact.”

Xu completed the study with graduate student Ran Li and senior author Brian Roe, professor in the Department of Agricultural, Environmental and Development Economics at Ohio State. The research was published recently in the British Food Journal.

Roe has been studying household food waste for years, but this is the first study to tease out where frozen food fits into the food waste picture. Recent estimates have suggested about 30% of food in the United States is wasted, but other research led by Roe suggests consumer food waste is trending upward.

“The fact that food waste is still increasing may suggest to policymakers that campaigns could be useful to educate households about balancing purchasing behavior and making the most of the food they buy,” Xu said.

The current study data comes from frozen food-related questions added to the summer 2022 wave of the U.S. National Household Food Waste Tracking Survey in which 1,067 households participated. Respondents were asked to estimate the percentage of all discarded food in the previous seven days that had been frozen and whether it was bought frozen or was unfrozen and placed in the freezer later. They also reported the typical frequency of buying frozen foods.

The responses indicated that 85% of U.S. households buy frozen foods and among those, 55% of participants reported they purchased frozen food to reduce waste. Frozen food purchasers were more likely to shop infrequently — two to three times per month — and were more likely to be living in households with annual income of under $50,000. The most common categories of discarded frozen foods were meat (20% of total frozen food waste), vegetables (22%) and potatoes and grains (15% each).

“Based on what we’re seeing among households, we still have space to increase awareness to save food by using freezing behavior,” Xu said.

Data showed a link between frequent home freezing and significantly less total food waste. Respondents most likely to freeze fresh items or extra food were aged 45 years and older and living in households of three or more people — a possible sign, the authors said, that consumers with a home freezing routine may be more experienced at managing meals for a group and motivated to avoid food waste.

What the team considered somewhat surprising — and enlightening — was the finding that about 30% more of wasted frozen food was discarded from the refrigerator than from the freezer.

“Thinking about why that happens, it might mean they don’t understand food storage techniques and don’t understand how long they should keep certain foods and where they should put it,” Xu said. “This suggests more explicit food storage instructions on food labels could educate consumers about how to correctly store foods to reduce waste.”

Trends in the data suggest that consumer education about the freezer’s role in saving food could make a difference economically and environmentally, Xu said, and also help address the societal problem of food insecurity experienced by 10% of U.S. households.

“Half of consumers buy frozen food to reduce waste. What about the other half?” she said. “We want to increase social awareness of how to save food, and explain how people use frozen food and home freezing techniques to save food. And freezing is one of the most accessible techniques because essentially all households have a refrigerator and freezer.”

This work was supported by the USDA National Institute of Food and Agriculture, the National Science Foundation and a gift from the Frozen Food Foundation that facilitated collection of a larger survey sample size.